Science.gov

Sample records for bridge deck pavement

  1. Research on tensile strength characteristics of bridge deck pavement bonding layers

    NASA Astrophysics Data System (ADS)

    Wu, Shaopeng; Han, Jun

    2010-03-01

    As the development of the traffic in the world, the bridge deck pavement is playing a more and more important role in the whole traffic system. Big span bridge has become more and more especially cement concrete bridge, therefore the bridge deck pavement bonding layers are emphasized as an important part of bridge traffic system, which can mitigate travel impact to bridge and magnify stationary or traffic amenity. The quality and durability of deck pavement bonding layer has directly effect on traffic safety, comfort, durability and investment of bridge. It represents the first line of defence against the ingress of water, road de-icing salts and aggressive chemicals. In real project, many early age damage of bridge deck pavement has become serious disease that affecting the function of bridge. During the construction of the bridge deck, many types of asphalt binders were used, such as styrene-butadiene-styrene (SBS) modified asphalt, styrene-butadiene rubber (SBR) modified asphalt, neoprene latex asphalt, etc. In this paper UTM-25 was used to test the tensile strength of different bridge deck pavement bonding layers with the different treatment methods to inter-surface.

  2. Research on tensile strength characteristics of bridge deck pavement bonding layers

    NASA Astrophysics Data System (ADS)

    Wu, Shaopeng; Han, Jun

    2009-12-01

    As the development of the traffic in the world, the bridge deck pavement is playing a more and more important role in the whole traffic system. Big span bridge has become more and more especially cement concrete bridge, therefore the bridge deck pavement bonding layers are emphasized as an important part of bridge traffic system, which can mitigate travel impact to bridge and magnify stationary or traffic amenity. The quality and durability of deck pavement bonding layer has directly effect on traffic safety, comfort, durability and investment of bridge. It represents the first line of defence against the ingress of water, road de-icing salts and aggressive chemicals. In real project, many early age damage of bridge deck pavement has become serious disease that affecting the function of bridge. During the construction of the bridge deck, many types of asphalt binders were used, such as styrene-butadiene-styrene (SBS) modified asphalt, styrene-butadiene rubber (SBR) modified asphalt, neoprene latex asphalt, etc. In this paper UTM-25 was used to test the tensile strength of different bridge deck pavement bonding layers with the different treatment methods to inter-surface.

  3. Plans: Poop Deck, Boat Deck, Housetop, Bridge Deck, Upper Bridge ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Plans: Poop Deck, Boat Deck, Housetop, Bridge Deck, Upper Bridge Deck, Navigating Bridge, Forecastle Deck, Upper Deck, Second Deck and Hold - Saugatuck, James River Reserve Fleet, Newport News, Newport News, VA

  4. Boat Deck, Cabin Deck, Bridge Deck, Flat House Top, Stage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Boat Deck, Cabin Deck, Bridge Deck, Flat House Top, Stage Top, Mast House Top, Upper Deck, Flat House Tops, Forecastle Deck, Main Deck - American Racer, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  5. Dog Bridge, view of the deck of the bridge and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Dog Bridge, view of the deck of the bridge and rails looking from Linden Lane - National Park Seminary, Bounded by Capitol Beltway (I-495), Linden Lane, Woodstove Avenue, & Smith Drive, Silver Spring, Montgomery County, MD

  6. Imaging radar for bridge deck inspection

    SciTech Connect

    Warhus, J.; Mast, J.; Nelson, S.

    1995-04-13

    Lawrence Livermore National Laboratory (LLNL)l is developing a prototype imaging radar for inspecting steel reinforced concrete bridge decks. The system is designed to acquire Synthetic Aperture Radar (SAR) data and provide high-resolution images of internal structure, flaws, and defects enabling bridge inspectors to nondestructively evaluate and characterize bridge deck condition. Concrete delamination resulting from corrosion of steel reinforcing bars (rebars) is an important structural defect that the system is designed to detect. The prototype system uses arrays of compact, low-cost Micropower Impulse Radar (MIR) modules, supported by appropriate data acquisition and storage subsystems, to generate and collect the radar data, and unique imaging codes to reconstruct images of bridge deck internals. In this paper, we provide an overview of the prototype system concept, discuss its expected performance, and present recent experimental results showing the capability of this approach to detect thin delamination simulations embedded in concrete.

  7. Epoxy coated reinforcement in bridge decks

    NASA Astrophysics Data System (ADS)

    Wills, J.

    A review was conducted of methods relating to the use of epoxy coated reinforcing bars for bridge decks and their potential for use in the United Kingdom. A survey of work carried out in the USA was carried out and the analysis used in a preliminary cost study. The options of having either a hot rolled asphalt surfacing or a permanently exposed concrete wearing surface were considered. It was concluded that epoxy coating of the top steel in addition to current waterproofing practice would provide, at relatively little extra cost, additional assurance that the reinforcement would be adequately protected throughout the life of a bridge. Current design rules do not permit decks with permanently exposed concrete wearing surface without waterproofing. Epoxy coating may afford a means of introducing such decks but before a positive recommendation to delete waterproofing can be made further studies would have to be undertaken.

  8. Embedded fiber optic sensors for bridge deck chloride penetration measurements

    NASA Astrophysics Data System (ADS)

    Fuhr, Peter L.; Huston, Dryver R.; MacCraith, Brian D.

    1998-04-01

    The use of chloride-based deicing agents to help clear U.S. highways of roadway hazards leads to associated chemical related problems. Fouling of local rivers and streams due to runoff of the waterborne chlorides is significant and has contributed to local ordinances that are attempting to force state agencies to reduce, if not eliminate, the use of these chlorides (typically at the cost of increased driving hazards). With respect to the corrosion aspects of chloride application, cracks that occur in the roadway/bridge pavement allow water to seep into the pavement carrying the chloride to the rebar with the resultant increase in corrosion. The costs of this corrosion are considerable and have led to the wide- spread use of chloride/water impermeable membranes on roadways and especially within bridges. Fiber optics sensors have repeatedly been shown to provide measurement capabilities of parameters within such reinforced concrete structures. Development of fiber optic chloride sensors capable of being embedded within a roadway or bridge deck is reported.

  9. Health monitoring of FRP bridge decks

    NASA Astrophysics Data System (ADS)

    Miceli, Marybeth; Horne, Michael R.; Duke, John C., Jr.

    2001-07-01

    Statistics released in the fall 1989 show that 238,357 (41%) of the nation's 577,710 bridges are either structurally deficient or functionally obsolete. New materials are being explored for use in bridge systems to solve this problem. These materials are less affected by corrosive environmental conditions than conventional civil engineering materials and thus, require less maintenance and potentially provide a longer life span. A material being considered for these applications is glass fiber reinforced vinyl ester matrix composites. Fiber reinforced plastic (FRP) composite deck systems made of this material are favorable potential replacements for deteriorating conventional bridge decks. The decreased specific weight of the FRP greatly reduces the dead load of the superstructure helping avoid load posting of bridges. However there is a lack of long-term durability data concerning this material system in typical bridge environments. Thus, an efficient and effective method must be devised to monitor the health of an FRP structure in-situ. This paper will discuss the use of Infrared Thermography as a means of detecting structural imperfections -- delaminations, disbonds, voids -- caused by conditions encountered both in fabrication and in the field. As forced convection hot air is circulated through the bridge deck, delaminations and disbonds in the top of the deck appear cold while defects in the bottom of the deck give rise to areas with higher temperatures. The discontinuities in thermal propagation patterns are detected with a thermal imaging system and indicate present and possible future structural deficiencies. Laboratory results revealing fabrication/installation problems and those from field tests will be presented.

  10. Improved ground-penetrating radar, bridge decks

    NASA Astrophysics Data System (ADS)

    Warhus, J. P.; Mast, J. E.; Johansson, E. M.; Nelson, S. D.

    1993-11-01

    Inspection of high-value structures, like bridges and buildings, using Ground Penetrating Radar (GPR) is an application of a technology that is growing in importance. In a typical inspection application, inspectors use GPR to locate structural components, like embedded reinforcing bars, to avoid weakening the structure while collecting core samples for detailed inspection. Advanced GPR, integrated with imaging technologies for use as an NDE tool, can provide the capability to quickly locate and characterize construction flaws and wear- or age-induced damage in these structures without resorting to destructive methods. In this paper, we discuss an important inspection application, namely, concrete bridge deck inspection. We describe an advanced bridge deck inspection system concept (Ground Penetrating Imaging Radar, GPIR) and present results from experiments designed to simulate the concept.

  11. Cracking behavior of structural slab bridge decks

    NASA Astrophysics Data System (ADS)

    Baah, Prince

    Bridge deck cracking is a common problem throughout the United States, and it affects the durability and service life of concrete bridges. Several departments of transportation (DOTs) in the United States prefer using continuous three-span solid structural slab bridges without stringers over typical four-lane highways. Recent inspections of such bridges in Ohio revealed cracks as wide as 0.125 in. These measured crack widths are more than ten times the maximum limit recommended in ACI 224R-01 for bridge decks exposed to de-icing salts. Measurements using digital image correlation revealed that the cracks widened under truck loading, and in some cases, the cracks did not fully close after unloading. This dissertation includes details of an experimental investigation of the cracking behavior of structural concrete. Prism tests revealed that the concrete with epoxy-coated bars (ECB) develops the first crack at smaller loads, and develops larger crack widths compared to the corresponding specimens with uncoated (black) bars. Slab tests revealed that the slabs with longitudinal ECB developed first crack at smaller loads, exhibited wider cracks and a larger number of cracks, and failed at smaller ultimate loads compared to the corresponding test slabs with black bars. To develop a preventive measure, slabs with basalt and polypropylene fiber reinforced concrete were also included in the test program. These test slabs exhibited higher cracking loads, smaller crack widths, and higher ultimate loads at failure compared to the corresponding slab specimens without fibers. Merely satisfying the reinforcement spacing requirements given in AASHTO or ACI 318-11 is not adequate to limit cracking below the ACI 224R-01 recommended maximum limit, even though all the relevant design requirements are otherwise met. Addition of fiber to concrete without changing any steel reinforcing details is expected to reduce the severity and extent of cracking in reinforced concrete bridge decks.

  12. Sonic inspection of concrete bridge decks

    NASA Astrophysics Data System (ADS)

    Costley, R. Daniel; Boudreaux, Gary; Ramsey, William Gene

    2003-10-01

    One technique for determining the integrity of concrete structures, such as bridge decks, involves dragging a chain across it and listening to the audible response. A distinctive, hollow sound is produced when a chain is dragged over a section of concrete containing a delamination. This technique has been automated by recording the sound produced by a dragging chain with a suitable microphone and processing these signals with a minicomputer to distinguish between ``good'' and ``bad'' sections of concrete. The equipment is mounted on a hand-pushed cart with chains attached so that they drag along the surface of the deck. In addition, the microphone is mounted in such a way, using standard noise control techniques, so that external noise is minimized. Traffic noise is filtered electronically. These improvements make the technique operator independent and allow inspections to be made in noisy environments. Another advantage is that this approach produces an objective record of the inspection, available both electronically and in hardcopy. These records can be compared to past and future inspections, allowing the inspectors to monitor the health of the structure. Results from bridge deck inspections will be presented, along with a description of the device and the signal processing techniques.

  13. 65. View from catwalk under bridge deck of the juncture ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    65. View from catwalk under bridge deck of the juncture of the original Crockett approach and the 1959 addition. View is near Tower 6. - Carquinez Bridge, Spanning Carquinez Strait at Interstate 80, Vallejo, Solano County, CA

  14. 11. DETAIL VIEW OF BRIDGE DECK, SHOWING ENDPANEL VERTICAL, ARCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF BRIDGE DECK, SHOWING END-PANEL VERTICAL, ARCH SEGMENT, LOWER CHORD AND FLOOR SYSTEM, LOOKING NORTHEAST - Davis Bridge, Spanning Upper Iowa River at County Road 16, Lime Springs, Howard County, IA

  15. 10. AN IMAGE, LOOKING DUE NORTH OF THE BRIDGE DECK, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. AN IMAGE, LOOKING DUE NORTH OF THE BRIDGE DECK, SHOWING LAYERS OF GRAVEL, ASPHALT AND TIMBER. - Wells County Bridge No. 74, Spanning Rock Creek Ditch at County Road 400, Bluffton, Wells County, IN

  16. 12. View underside of bridge, showing concrete tee beam deck ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. View underside of bridge, showing concrete tee beam deck spans supported by concrete piles, looking southwest - Colonel Alexander Scammell Memorial Bridge, Spanning Bellamy River at U.S. Route 4, Dover, Strafford County, NH

  17. DETAIL VIEW OF SINGLE PANEL POINTS TAKEN FROM BRIDGE DECK, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW OF SINGLE PANEL POINTS TAKEN FROM BRIDGE DECK, SHOWING CONNECTION BETWEEN VERTICAL AND UPPER CHORD MEMBER - White Bowstring Arch Truss Bridge, Spanning Yellow Creek at Cemetery Drive (Riverside Drive), Poland, Mahoning County, OH

  18. 11. DETAIL VIEW OF UNDERSIDE OF BRIDGE SHOWING DECK SUPPORT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF UNDERSIDE OF BRIDGE SHOWING DECK SUPPORT SYSTEM, LOOKING SOUTHWEST - Springfield-Des Arc Bridge, Spanning North Branch of Cadron Creek at Old Springfield-Des Arc Road (County Road 222), Springfield, Conway County, AR

  19. 51. Bridge nearing completion, note formwork for deck cantilever, south ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    51. Bridge nearing completion, note formwork for deck cantilever, south abutment; view to east. Note lack of connection to roadway at right. - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  20. QUEENS TOWER, BRONXWHITESTONE BRIDGE, NOTE PLATE GIRDER DECK TRUSS AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    QUEENS TOWER, BRONX-WHITESTONE BRIDGE, NOTE PLATE GIRDER DECK TRUSS AND LATER ADDED WARREN TRUSS IN ADDITION TO DIAGONAL STAYS - Bronx-Whitestone Bridge, Spanning East River between Whitestone, Queens & the Bronx, Bronx, Bronx County, NY

  1. 8. Detail of underside of bridge deck, from the southern ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Detail of underside of bridge deck, from the southern end looking toward north-northwest. - Bridge No. 4800, Spanning Minnesota River on Trunk Highway 4 between Brown & Nicollet Counties, Sleepy Eye, Brown County, MN

  2. PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK POUR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK POUR, VIEW TO NORTH. - Rex T. Barber Veterans Memorial Bridge, Spanning Crooked River Gorge, Dalles-California Highway (US 97), Terrebonne, Deschutes County, OR

  3. PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK POUR, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK POUR, VIEW TO NORTHWEST SHOWING HIGH LINE SYSTEM. - Rex T. Barber Veterans Memorial Bridge, Spanning Crooked River Gorge, Dalles-California Highway (US 97), Terrebonne, Deschutes County, OR

  4. DETAIL PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL PERSPECTIVE VIEW OF THE REX T. BARBER BRIDGE DECK POUR, VIEW TO NORTHEAST. - Rex T. Barber Veterans Memorial Bridge, Spanning Crooked River Gorge, Dalles-California Highway (US 97), Terrebonne, Deschutes County, OR

  5. South Elevation; Deck Plan Shoreham Railroad Bridge, Former Addison ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    South Elevation; Deck Plan - Shoreham Railroad Bridge, Former Addison County Railroad (later, Rutland Railroad, Addison Branch), spanning Lemon Fair River above Richville Pond, west of East Shoreham Road, Shoreham, Addison County, VT

  6. 26. VIEW OF BRIDGE DECK ON SPAN 8, SHOWING TOP, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. VIEW OF BRIDGE DECK ON SPAN 8, SHOWING TOP, DIAGONAL AND VERTICAL CHORDS AND GUSSET PLATE ON SOUTHEAST CORNER OF TRUSS, LOOKING EAST - West End-North Side Bridge, Spanning Ohio River, approximately 1 mile downstream from confluence of Monongahela & Allegheny rivers, Pittsburgh, Allegheny County, PA

  7. North elevation of lift bridge. Plywood decking is not original. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    North elevation of lift bridge. Plywood decking is not original. Note portion of R. Paul Smith Power Station in left background. - Potomac Edison Company, Chesapeake & Ohio Canal Bridge, Spanning C & O Canal South of U.S. 11, Williamsport, Washington County, MD

  8. 14. NORTH FORK VIRGIN RIVER BRIDGE DECK UNDER RECONSTRUCTION. REINFORCING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. NORTH FORK VIRGIN RIVER BRIDGE DECK UNDER RECONSTRUCTION. REINFORCING ROD IN PLACE. PHOTO BY CARL E. JEPSON, 29 JANUARY 1960. - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  9. With deck removed and critical members severed, the bridge begins ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    With deck removed and critical members severed, the bridge begins to succumb to tractors, pulling cables attached to its downstream side. View is to the southeast from confluence of Trinity and South Fork Trinity Rivers - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

  10. Issues in bridge deck damage evaluation using aerial photos

    NASA Astrophysics Data System (ADS)

    Natarajan, M.; Chen, S. E.; Boyle, C.; Martin, E.; Hauser, E.

    2012-04-01

    Small format aerial photography (SFAP) with low flying technique is proposed for damage evaluation of bridge decks. High resolution images obtained using under-belly photography can be used to quantify the various bridge deck problems. The conventional truck-mount or vehicle-mount deck imaging technologies require a large number of image samples. Hence the physical scanning is time consuming and it is also challenging consider the size and location of a bridge. Aerial imaging overcomes these issues, but they face different kinds of challenges that are posed by obstacles such as shadow from trees, power lines and vehicles, signs and luminaries structures. The image resolution uncertainty, which is a function of the pilot skills and flying conditions, may also add additional challenges to aerial imaging technique. Hence different image processing tools have to be integrated into a single package to achieve the desired task. This paper summarizes the challenges faced and the preliminary results are presented and discussed.

  11. Bridge deck joints evaluation using lidar and aerial photography

    NASA Astrophysics Data System (ADS)

    Bian, Haitao; Chen, Shen-En; Watson, Christopher; Hauser, Edd

    2011-04-01

    Deck joint is important for a bridge - Any cost-effective evaluation methods that can help trace joint movements during frequent inspections will provide valuable data to bridge engineers. In this paper, 3D Terrestrial LiDAR and Aerial photography are being investigated as possible joint evaluation methods. The laser scanners record 3D positions of the surface points, generating high density point clouds. Aerial images taken by commercial DSLR cameras in a small airplane flying at 1000 feet, generates high resolution imagery. Both techniques have sub-inch pixel resolutions. Scanning results from bridges in both Florida and Alabama have shown that LiDAR and aerial imaging technologies are compatible techniques and can be applied in bridge deck joint performance evaluation. Moreover, both techniques have the potential to reduce the costs in bridge inspection.

  12. Simulation studies of damage location in Tsing Ma Bridge deck

    NASA Astrophysics Data System (ADS)

    Ni, Yi-Qing; Wang, Bai S.; Ko, Jan Ming

    2000-06-01

    This paper addresses the identification of damage region and location in the Tsing Ma Suspension Bridge deck using modal data. A two-stage identification method is proposed and implemented through numerical simulation for damage detection of the bridge deck. In the first stage, the main span deck of 1377 m length is divided into seventy-six segments and the target in this stage is to determine the deck segment that contains damaged member(s). An index vector derived from mode shape curvatures in both intact and damaged states is presented to identify the damage region (segment). In the second stage, the specific damaged member(s) within the damage region is identified by means of a neural network technique. The combined modal parameters in terms of natural frequencies and a few incomplete modal vectors are adopted as input vector to the neural networks. Two back-propagation networks are trained for the damage location detection. The simulation results show that despite very low modal sensitivity of the bridge to deck member damage, the developed method can still locate the damage at longitudinal structural members such as bottom chords, top chords, and diagonal members.

  13. EARTHQUAKE PERFORMANCE OF A BRIDGE DECK AND ABUTMENT.

    USGS Publications Warehouse

    Celebi, M.; Brady, G.

    1985-01-01

    During the 24 April 1984 Morgan Hill Earthquake (M equals 6. 1), 15 channels of acceleration records were obtained at the site of the I-280-680/US 101 interchange 12 km west of the epicenter. These records include free field measurements as well as the acceleration response at one of the supporting column bases, and at three locations in one of the spans of the three-span continuous post-tensioned box-girder deck. The purpose of this paper is to review the performance of this bridge deck and its abutment through the study of these records. The objective in extensively instrumenting a bridge deck or any structure is to obtain relevant response data to study its behaviour during strong motion events and ultimately extrapolate conclusions for improved design.

  14. Deck plate girder spans and steel piers of Bridge No. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Deck plate girder spans and steel piers of Bridge No. 1396, Fourth Potomac and Second B&O Crossing, over original B&O right of way (right) and flood plain (left), looking west. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  15. Development of Aluminum Bridge Deck System with Reynolds Metals Company

    SciTech Connect

    Brinkman, C.R.; Hayden, W.H.

    1999-04-01

    Currently, there are many structurally-deficient and obsolete bridges in the US highway system. The expected cost for repair and replacement is enormous; therefore, more cost-effective materials and construction methodology must be sought. Reynolds Metals Company formed a vertical consortium to develop and market a cost-effective, innovative, lightweight, corrosion resistant aluminum bridge deck system based on hollow aluminum shapes that could be welded together in the shop to form deck panels. Panels would be shipped to the construction sites for final assembly, which uses connections along longitudinal edges. These deck panels would replace conventional steel or concrete panels. An epoxy-gravel wearing surface would be applied to the top side of the deck to provide a durable, skid-resistant surface. However, before this deck system could be widely utilized, the overall structural integrity had to be fully demonstrated. Reynolds Metals Company and Oak Ridge National Laboratory (ORN L) entered in a Cooperative Research and Development Agreement (CRADA) to conduct a number of fundamental investigations into potentially critical technical areas over approximately a four-year period.

  16. Concrete bridge deck early problem detection and mitigation using robotics

    NASA Astrophysics Data System (ADS)

    Gucunski, Nenad; Yi, Jingang; Basily, Basily; Duong, Trung; Kim, Jinyoung; Balaguru, Perumalsamy; Parvardeh, Hooman; Maher, Ali; Najm, Husam

    2015-04-01

    More economical management of bridges can be achieved through early problem detection and mitigation. The paper describes development and implementation of two fully automated (robotic) systems for nondestructive evaluation (NDE) and minimally invasive rehabilitation of concrete bridge decks. The NDE system named RABIT was developed with the support from Federal Highway Administration (FHWA). It implements multiple NDE technologies, namely: electrical resistivity (ER), impact echo (IE), ground-penetrating radar (GPR), and ultrasonic surface waves (USW). In addition, the system utilizes advanced vision to substitute traditional visual inspection. The RABIT system collects data at significantly higher speeds than it is done using traditional NDE equipment. The associated platform for the enhanced interpretation of condition assessment in concrete bridge decks utilizes data integration, fusion, and deterioration and defect visualization. The interpretation and visualization platform specifically addresses data integration and fusion from the four NDE technologies. The data visualization platform facilitates an intuitive presentation of the main deterioration due to: corrosion, delamination, and concrete degradation, by integrating NDE survey results and high resolution deck surface imaging. The rehabilitation robotic system was developed with the support from National Institute of Standards and Technology-Technology Innovation Program (NIST-TIP). The system utilizes advanced robotics and novel materials to repair problems in concrete decks, primarily early stage delamination and internal cracking, using a minimally invasive approach. Since both systems use global positioning systems for navigation, some of the current efforts concentrate on their coordination for the most effective joint evaluation and rehabilitation.

  17. Dual-band infrared imaging for concrete bridge deck inspection

    SciTech Connect

    Durbin, P.; Del Grande, N.

    1994-02-01

    Dual-band infrared (DBIR) imaging methods and unique image-correction algorithms used successfully for underground and obscured object imaging and detection (of buried mines, archaeological structures, geothermal aquifers and airframe defects) are adapted for inspection of concrete highways and bridge decks to provide early warnings of subsurface defects. To this end, we prepared small concrete test slabs with defects (embedded plastic layers). We used selective DBIR (3--5 {mu}m and 8--12 {mu}m) image ratios to depict the defect sites and remove the effects of surface clutter. We distinguish true temperature-difference signals (at surrogate delamination sites) from emissivity noise (at sites with oil stains, sand, gravel, metal parts and roughness differences) towards improved concrete bridge deck inspections.

  18. Vertical impedance measurements on concrete bridge decks for assessing susceptibility of reinforcing steel to corrosion.

    PubMed

    Bartholomew, Paul D; Guthrie, W Spencer; Mazzeo, Brian A

    2012-08-01

    Corrosion is a pressing problem for aging concrete infrastructure, especially bridge decks. Because of its sensitivity to factors that affect corrosion of reinforcing steel in concrete, resistivity is an important structural health indicator for reinforced concrete structures. In this research, an instrument was developed to measure vertical impedance on concrete bridge decks. Measurements of vertical impedance on slabs prepared in the laboratory, on slabs removed from decommissioned bridge decks, and on an in-service bridge deck in the field demonstrate the utility of the new apparatus. PMID:22938329

  19. Thermal infrared inspection of FRP bridge decks for health monitoring

    NASA Astrophysics Data System (ADS)

    Miceli, Marybeth; Duke, John C.; Horne, Michael

    2003-04-01

    Even in the best of economic times, funding for infrastructure maintenance, repair and rehabilitation is never adequate. As infrastructure in the United States continues to age, the funding deficit to simply maintain the existing bridges will continue to soar. Due to the inadequacy of capital allocated for infrastructure repair and rehabilitation, new, more durable construction materials with potentially longer service lives are being explored as a means of narrowing the financial deficit. One such material is fiber reinforced polymer matrix composites (FRP). By replacing conventional bridge component structural materials (i.e.; reinforced concrete and steel) with FRP, which has a higher strength to weight ratio, bridges can achieve a significant reduction in dead load weight. Bridges that have experienced substructure and superstructure deterioration can undergo a superstructure replacement with FRP rather than be subjected to the traditional load posting (vehicular load restrictions). Through reducing the bridge dead load without compromising bridge strength, original design live loads can be maintained. In order for these new bridge superstructure components to be readily accepted as viable construction materials, quick and effective means of monitoring them for degradation and overall structural health must be established and standardized. One of the most promising methods of achieving this is through the use of thermal infrared (TIR). A slight increase in temperature above ambient will allow for adequate inspection of large sections of bridge decking for detection of debonded areas between FRP components. This paper illustrates the successes and challenges of using TIR for this purpose, both in the laboratory and in field investigations. Areas for future work and improvements will be suggested.

  20. 10. DETAIL VIEW OF BRIDGE DECK, SHOWING TYPICAL VERTICAL/OUTRIDER, ARCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DETAIL VIEW OF BRIDGE DECK, SHOWING TYPICAL VERTICAL/OUTRIDER, ARCH SEGMENT AND DIAGONALS, LOOKING NORTH - Davis Bridge, Spanning Upper Iowa River at County Road 16, Lime Springs, Howard County, IA

  1. Linear and Non-linear Analysis of Fibre Reinforced Plastic Bridge Deck due to Vehicle Loads

    NASA Astrophysics Data System (ADS)

    Ray, Chaitali; Mandal, Bibekananda

    2015-06-01

    The present work deals with linear and nonlinear static analysis of fibre reinforced plastics composite bridge deck structures using the finite element method. The nonlinear static analysis has been carried out considering geometric nonlinearity. The analysis of bridge deck has been carried out under vehicle load as specified by IRC Class B wheel load classification. The formulation has been carried out using the finite element software package ANSYS 14.0 and the SHELL281 element is used to model the bridge deck. The bridge deck has also been modeled as a plate stiffened with closely spaced hollow box sections and a computer code is developed based on this formulation. The results obtained from the present formulation are compared with those available in the published literature. A parametric study on the stiffened bridge deck has also been carried out with varying dimensions of the stiffeners under vehicle loads.

  2. Computational Fluid Dynamic Analysis of Hydrodynamic forces on inundated bridge decks

    NASA Astrophysics Data System (ADS)

    Afzal, Bushra; Guo, Junke; Kerenyi, Kornel

    2010-11-01

    The hydraulic forces experienced by an inundated bridge deck have great importance in the design of bridges. Flood flows or hurricane add significant hydrodynamic loading on bridges, possibly resulting in failure of the bridge superstructures. The objective of the study is to establish validated computational practice to address research needs of the transportation community via computational fluid dynamic simulations. The reduced scale experiments conducted at Turner-Fairbank Highway Research Center establish the foundations of validated computational practices to address the research needs of the transportation community. Three bridge deck prototypes were used: a typical six-girder highway bridge deck, a three-girder deck, and a streamlined deck designed to better withstand the hydraulic forces. Results of the study showed that the streamlined deck significantly reduces drag, lift, and moment coefficient in comparison to the other bridge deck types. The CFD results matched the experimental data in terms of the relationship between inundation ratio and force measured at the bridge. The results of the present research will provide a tool for designing new bridges and retrofitting old ones.

  3. Multisensor data fusion and visualization for impact echo testing of bridge decks

    NASA Astrophysics Data System (ADS)

    Wei, Xiangmin; Xie, Zhenhua; Zhang, Ying

    2012-04-01

    An effective multisensor data fusion and visualization framework is proposed for accurate localization and effective visualization of delamination in concrete bridge decks based on impact echo (IE) nondestructive evaluation method. The fusion rules are developed by analyzing the spatial distribution of surface motion resulting from mechanical impacts applied at different locations based on numerical simulation. The proposed approach can process, integrate and interpret the data from a series IE source-receiver arrays to improve the accuracy and reliability of delamination characterization for bridge decks. The visualization approach provides an intuitive way for users to visualize the internal defects of concrete bridge decks.

  4. Health monitoring of precast bridge deck panels reinforced with glass fiber reinforced polymer bars

    NASA Astrophysics Data System (ADS)

    Ries, James Mcdaniel

    The Beaver Creek Bridge on US highway 6 is the pilot project for Glass Fiber Reinforced Polymer (GFRP) bridge decks and posttensioned bridge decks in the state of Utah. The bridge was built in 2009, using accelerated bridge construction practices, including the use of precast prestressed girders, as well as precast decking. The westbound bridge decking was composed of 12 precast panels each measuring 41'-5" long, 6'-10" wide, and 9¼" thick, and weighing approximately 33 kips. At the time, these panels were the longest GFRP panels in the United States. The Utah Department of Transportation has decided to evaluate GFRP reinforcing bars as an alternative to steel rebar in this bridge deck. The hope is to increase the lifespan of bridge decks to match the service life of the entire bridge. Due to the nature of the GFRP bars, the panels were lifted at four points using straps instead of imbedded anchors. During the four-point lifting, the panels exhibited small deflections and strains; furthermore, no cracks larger than hairline cracks were found in the panels after lifting. The Beaver Creek Bridge deck is the first precast deck in the state of Utah to be posttensioned in the direction of traffic. Posttensioning bridge decks is expected to become the norm in the state of Utah. The posttensioning resulted in increased continuity between panels. In order to quantify the expected performance of the bridge during its service life, a truck load test was performed. The truck load test was comprised of a static and dynamic test. During the truck load test, the bridge experienced deflections in the panels which were 93% below design values. Girder deflections were also small. The use of GFRP bars has the potential to extend the life of bridge decks exposed to deicing salts from 45 years to 100 years, while only requiring an increased capital cost in the bridge of 8%. Furthermore, the use of GFRP bars in conjunction with accelerated building practices has the potential to reduce long-term user delays resulting from maintenance. The difference in capital cost could decrease as designers become more comfortable with the material and gain experience with the system.

  5. Wind tunnel investigations of aerodynamic coefficients of road vehicles on bridge deck

    NASA Astrophysics Data System (ADS)

    Zhu, L. D.; Li, L.; Xu, Y. L.; Zhu, Q.

    2012-04-01

    To assess the safety of road vehicles running over a long span bridge in high wind, the knowledge of aerodynamic forces and moments on the vehicles is required. This could be obtained through wind tunnel investigations and expressed in terms of aerodynamic coefficients. However, very few investigations have been carried out to find aerodynamic coefficients of road vehicles on a bridge deck, compared with the aerodynamic coefficients of road vehicles on the ground. This paper therefore presents the results of wind tunnel tests carried out to determine aerodynamic coefficients of four types of road vehicles over a typical bridge deck. The aerodynamic coefficients of the same road vehicles on the ground are also presented to explore the effects of the bridge deck on aerodynamic coefficients. Different wind directions are taken into consideration to observe variations of aerodynamic coefficients with wind direction. Furthermore, the effects of vehicle position in different road lanes of the bridge deck are investigated. The test results show that the existence of bridge deck reduces side forces for all four types of vehicles remarkably but increases rolling moments to some extent. Such effects also vary with types of vehicles and lanes of the bridge deck where vehicles run.

  6. Modelling of pavement materials on steel decks using the five-point bending test: Thermo mechanical evolution and fatigue damage

    NASA Astrophysics Data System (ADS)

    Arnaud, L.; Houel, A.

    2010-06-01

    This paper deals with the modelling of wearing courses on steel orthotropic decks such as the Millau viaduct in France. This is of great importance when dealing with durability: due to the softness of such a support, the pavement is subjected to considerable strains that may generate top-down cracks in the layer at right angles of the orthotropic plate stiffeners and shear cracks at the interface between pavement and steel. Therefore, a five-point bending fatigue test was developed and improved since 2003 at the ENTPE laboratory, to test different asphalt concrete mixes. This study aims at modelling the mechanical behavior of the wearing course throughout the fatigue test by a finite element method (Comsol Multiphysics software). Each material - steel, sealing sheet, asphalt concrete layer - is considered and modelled. The modelling of asphalt concrete is complex since it is a heterogeneous material, a viscoelastic medium and it thermosensitive. The actual characteristics of the asphalt concrete (thermo physical parameter and viscoelastic complex modulus) are determined experimentally on cylindrical cores. Moreover, a damage law based on Miner's damage is included in the model. The modelling of the fatigue test leads to encouraging results. Finally, results from the model are compared to the experimental data obtained from the five-point bending fatigue test device. The experimental data are very consistent with the numerical simulation.

  7. Crack mitigation in concrete bridge decks through experimental analysis and computer modeling

    NASA Astrophysics Data System (ADS)

    Richardson, Douglas M.

    Bridge deck cracking can cause deterioration of bridge decks, leading to a shorter life span and poor performance. Throughout the US, cracking has been identified as a problem, with transverse cracking along the deck at regular spacings being the most prominent type. This problem is usually caused by drying shrinkage within the concrete. The material properties, restraint, and distances without expansion joints all affect the crack pattern within the deck. This study will delve into the reasons that bridge decks crack, the strains that are associated with drying shrinkage, and possible methods for abating its effects. The research is divided into two parts, the first being laboratory experimentation, which was conducted through the use of two 7 ft. x 10 ft. experimental concrete bridge bays. Each bay was instrumented with strain and temperature gages throughout the deck and girders, which collected data for six months. The first deck was poured with a control concrete mix used currently in Illinois. The second deck was poured with a type K expansive concrete, which could battle the effects of shrinkage. For both decks, the results suggest a compressive strain throughout the rebar and along the top surface of the concrete, except for the locations where cracks are found (at these locations the strain slopes upward into tension). The strain in the type K deck, though, was notably less than that in the control deck and the onset of cracking was delayed by three weeks, giving the indication of an improvement over the current mix design. The second portion of the research was focused on using a finite element model to replicate the bridge bay and study the results. Equivalent temperature loading was used to apply the shrinkage loads recorded during the experimental portion of the research. The model was then expanded to encompass a full-scale bridge and in order to provide some insight into shrinkage strain in the real world. The end goal is to help alleviate cracking in current bridge decks, as well as create suggestions for future bridge construction.

  8. Analytical Study of Vertical and Torsional Free Vibration of Cable Supported Bridge Decks

    NASA Astrophysics Data System (ADS)

    Gorman, Daniel J.

    The superposition method is employed to obtain an analytical type solution for the free vibration of cable supported bridge decks. Each pair of vertical elastic cables is considered to impart a vertical force to the deck by means of a rigid cross-member passing transversely beneath it. Rigid knife-edge support encountered at bridge towers is handled as well. In this introductory study the deck is treated as a thin isotropic plate. Any number of support cable pairs, of any stiffness, may be handled. Inter cross-member distances are referred to as spans. Free vibration eigenvalues and mode shapes are presented for three and four span illustrative cases.

  9. EXPERIMENTAL STUDY ON THE MECHANISM OF HORIZONTAL AND VERTICAL WAVE FORCES ACTING ON A BRIDGE DECK SUBJECTED TO BREAKER BORES

    NASA Astrophysics Data System (ADS)

    Shoji, Gaku; Hiraki, Yu; Ezura, Yoshiyuki; Iidaka, Minoru; Fujima, Koji; Shigihara, Yoshinori

    The 2011 off the Pacific Coast of Tohoku earthquake tsunami caused the catastrophic damage of infrastructures such as coastal structures, utilities and transportation facilities. Among infrastructures evaluation of tsunami fluid force acting on a bridge deck is urgently required for designing a tsunami-proof bridge structure. Authors carried out hydraulic experiments by using high-speed camera to clarify the mechanism of horizontal and vertical wave forces acting on a bridge deck subjected to plunging breaker bores and surging breaker bores, focusing on the relationship between the position of a bridge deck against wave height and the occurrence of horizontal and vertical wave forces acting on a bridge deck.

  10. 12. ANNISQUAM BRIDGE, LOOKING WEST ALONG DECK, C.1885. Photocopy of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. ANNISQUAM BRIDGE, LOOKING WEST ALONG DECK, C.1885. Photocopy of photograph (original glass plate negative #T14 in the collection of the Annisquam Historical Society, Annisquam, Massachusetts). Photographer: Martha Harvey (1862-1949). - Annisquam Bridge, Spanning Lobster Cove between Washington & River Streets, Gloucester, Essex County, MA

  11. Unmanned Ground Vehicle for Autonomous Non-Destructive Testing of FRP Bridge Decks

    NASA Astrophysics Data System (ADS)

    Klinkhachorn, P.; Mercer, A. Scott; Halabe, Udaya B.; GangaRao, Hota V. S.

    2007-03-01

    Current non-destructive techniques for defect analysis of FRP bridge decks have a narrow scope. These techniques are very good at detecting certain types of defects but are not robust enough to detect all defects by themselves. For example, infrared thermography (IRT) can detect air filled defects and Ground Penetrating Radar (GPR) is good at detecting water filled ones. These technologies can be combined to create a more robust defect detection scheme. To accomplish this, an Unmanned Ground Vehicle (UGV) has been designed that incorporates both IR and GPR analysis to create a comprehensive defect map of a bridge deck. The UGV autonomously surveys the deck surface and acquires data. The UGV has two 1.5 GHz ground coupled GPR antennas that are mounted on the front of the UGV to collect GPR data. It also incorporates an active heating source and a radiometric IR camera to capture IR images of the deck, even in less than ideal weather scenarios such as cold cloudy days. The UGV is designed so that it can collect data in an assembly line fashion. It moves in 1 foot increments. When moving, it collects GPR data from the two antennas. When it stops it heats a section of the deck. The next time it stops to heat a section, the IR camera is analyzing the preheated deck section while preparing for the next section. Because the data is being continually collected using this method, the UGV can survey the entire deck in an efficient and timely manner.

  12. On the aeroelastic transient behaviour of a streamlined bridge deck section in a wind tunnel

    NASA Astrophysics Data System (ADS)

    Manzoor, S.; Hmon, P.; Amandolese, X.

    2011-11-01

    The study deals with the transient behaviour of a two degrees of freedom bridge deck section in a wind tunnel under the effect of an initial excitation. Response of the bridge deck section subjected to an initial mechanical excitation and excitation by an upstream gust is investigated separately. Experiments are conducted with three different frequency ratios between the plunge and pitch degrees of freedom. This experimental study shows that transient growth of energy occurs for wind velocities below the onset of flutter, reaching a level higher than 5 times the level of the initial excitation. In high wind conditions, this means that statistical or spectral computation techniques might underestimate the motion amplitude reached by a flexible bridge deck. This emphasises the importance of using temporal techniques under such circumstances.

  13. Development of early age shrinkage stresses in reinforced concrete bridge decks

    NASA Astrophysics Data System (ADS)

    William, Gergis W.; Shoukry, Samir N.; Riad, Mourad Y.

    2008-12-01

    This paper describes the instrumentation and data analysis of a reinforced concrete bridge deck constructed on 3-span continuous steel girders in Evansville, West Virginia. An instrumentation system consisting of 232 sensors is developed and implemented specifically to measure strains and temperature in concrete deck, strains in longitudinal and transverse rebars, the overall contraction and expansion of concrete deck, and crack openings. Data from all sensors are automatically collected every 30 minutes starting at the time of placing the concrete deck. Measured strain and temperature time-histories were used to calculate the stresses, which were processed to attenuate the thermal effects due to daily temperature changes and isolate the drying shrinkage component. The results indicated that most of concrete shrinkage occurs during the first three days. Under the constraining effects from stay-in-place forms and reinforcement, early age shrinkage leads to elevated longitudinal stress, which is the main factor responsible for crack initiation.

  14. Using emissivity-corrected thermal maps to locate deep structural defects in concrete bridge decks

    SciTech Connect

    Del Grande, N.K.; Durbin, P.F.

    1995-04-05

    Dual-band infrared (DBIR) thermal imaging is a promising, non-contact, nondestructive evaluation tool to evaluate the amount of deteriorated concrete on asphalt-covered bridge decks. We conducted proof-of-principle demonstrations to characterize defects in concrete structures which could be detected with DBIR thermal imaging. We constructed two identical concrete slabs with synthetic delaminations, e.g., 1/8-in. thick styrofoam squares, implanted just above the 2-in.-deep steel reinforcement bars. We covered one of the slabs with a 2-in. layer of asphalt. We mounted the DBIR cameras on a tower platform, to simulate the optics needed to conduct bridge-deck inspections from a moving vehicle. We detected 4-in. implants embedded in concrete and 9-in. implants embedded in asphalt-covered concrete. The midday (above-ambient) and predawn (below-ambient) delamination-site temperatures correlated with the implant sizes. Using DBIR image ratios, we enhanced thermal-contrast and removed emissivity-noise, e.g., from concrete compositional variations and clutter. Using the LLNL/VIEW code, we removed the asphalt thermal-gradient mask, to depict the 4-in. deep, 9-in. square, concrete implant size. We plan to image bridge deck defects, from a moving vehicle, for accurate estimations of the amount of deteriorated concrete impairing the deck integrity. Potential longterm benefits are affordable and reliable rehabilitation for asphalt-covered decks.

  15. 1. View,looking east,of the deck of the bridge taken from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. View,looking east,of the deck of the bridge taken from the intersection of w. 25th Street and Detroit Avenue. The bridge connects the city's east and west side over the Cuyahoga River Valley. Photograph illustrates the flared approaches designed to accommodate an, open well, through which streetcars could enter the bridge's lower level. This plan was later abandoned after construction had already begun, in favor of short subways that would carry the streetcars west beneath Detroit Avenue for a distance of 725 feet and south beneath W. 25th St. for a distance of 560 feet. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

  16. Characterization of stormwater runoff from bridges in North Carolina and the effects of bridge deck runoff on receiving streams

    USGS Publications Warehouse

    Wagner, Chad; Fitzgerald, Sharon A.; Sherrell, Roy D.; Harned, Douglas A.; Staub, Erik L.; Pointer, Brian H.; Wehmeyer, Loren L.

    2011-01-01

    In 2008, the North Carolina General Assembly passed House Bill 2436 that required the North Carolina Department of Transportation (NCDOT) to study the water-quality effects of bridges on receiving streams. In response, the NCDOT and the U.S. Geological Survey (USGS) collaborated on a study to provide information necessary to address the requirements of the Bill. To better understand the effects of stormwater runoff from bridges on receiving streams, the following tasks were performed: (1) characterize stormwater runoff quality and quantity from a representative selection of bridges in North Carolina; (2) measure stream water quality upstream from selected bridges to compare bridge deck stormwater concentrations and loads to stream constituent concentrations and loads; and (3) determine if the chemistry of bed sediments upstream and downstream from selected bridges differs substantially based on presence or absence of a best management practice for bridge runoff.

  17. Experimental Analysis of Stiffness of the Riveted Steel Railway Bridge Deck Members' Joints

    NASA Astrophysics Data System (ADS)

    Gocl, Jozef; Hlinka, Richard; Jot, Jozef; Bahleda, Frantiek

    2014-12-01

    The paper deals with the real behaviour of the riveted steel railway bridge deck members' connections with respect to their bending stiffness. Attention is paid to the stringer-to-cross beam connection as well as the cross beam-to-main girder connection. The stiffness of the two connections is investigated on the basis of evaluation of the experimentally determined stress response of the observed structural members to the actual traffic load on an existing railway bridge.

  18. Cross-spectral recognition method of bridge deck aerodynamic admittance function

    NASA Astrophysics Data System (ADS)

    Zhao, Lin; Ge, Yaojun

    2015-12-01

    This study proposes a new identification algorithm about the admittance function, which can estimate the full set of six aerodynamic admittance functions considering cross power spectral density functions about the forces and the turbulence components. The method was first numerically validated through Monte Carlo simulations, and then adopted to estimate the aerodynamic admittance of a streamlined bridge deck. The identification method was further validated through a comparison between the numerical calculation and wind tunnel tests on a moving bridge section.

  19. Fabry-Perot sensors for the monitoring of FRP reinforced bridge decks

    NASA Astrophysics Data System (ADS)

    Benmokrane, Brahim; Quirion, Marco; El-Salakawy, Ehab; Debaiky, Ahmed S.; Lackey, Tom

    2004-07-01

    The extensive use of deicing salts in Canada during winter times is identified as the main reason behind the deterioration of highway bridges and parking garages. To fight this infrastructure crisis, Fibre Reinforced Polymers (FRP) has become a very attractive alternative to traditional reinforcing steel due to their non-corrosive nature and light weight. The replacement of steel with Glass FRP bars in bridge deck slabs has been extensively researched in the last few years. This paper presents the first efforts to implement these bars in two highway bridges in Quebec, Canada, and Vermont, USA. These projects are aimed to prove the feasibility of using GFRP bars in bridge construction. GFRP bars were used as reinforcement for parts of the deck slabs in the two bridges while traditional steel was used in the remaining parts. Fibre Optic Sensors (FOS) were used to measure strains in the concrete, reinforcing bars and steel girders. The sensors were surface mounted on the bars or steel girders using standard glue, or embedded in concrete. Static and dynamic testing of the bridges was done using loaded trucks placed for maximum stresses. The design, construction, testing, and results obtained from the bridges are briefly outlined in this paper. The results indicated the accuracy of the sensors and their feasibility for bridge construction and remote monitoring.

  20. Evaluation of Fiber Optic Strain Measurement System for Monitoring FRP Bridge Decks

    NASA Astrophysics Data System (ADS)

    Klinkhachorn, P.; Lonkar, G. M.; Halabe, Udaya B.; GangaRao, H. V. S.

    2005-04-01

    The use of Fiber Optic sensors for structural monitoring applications has attained popularity among researchers and practitioners recently due to their immense advantages. This paper discusses a continuous structural monitoring technique using surface mounted and embedded fiber optic strain sensors to measure the strain in FRP bridge decks. An Extrinsic Fabry-Perot Interferometric (EFPI) strain sensor was selected for evaluation as it offers a good compromise between accuracy and cost considerations. This EFPI strain sensor, along with a conventional strain gauge, was surface mounted on a FRP bridge decks. The decks were then subjected to an accelerated aging test in an environmental chamber and the performance of both the strain sensors was recorded for a performance comparison. The results from the seven months of accelerated aging that is equivalent to 10 years of actual life show that the strain gauge sensor and the EFPI Fiber Optic sensor are still in working condition. The EFPI fiber optic sensor detects minute and sudden changes in strain more effectively than the strain gauge sensor. Placement in the environmental chamber did not affect the EFPI sensor's performance and is an indication of its applicability to field structural monitoring for lengthy periods of time. The second part is a preliminary work where a fiber optic sensor was embedded inside a FRP plate during the pultrusion process. This shows the feasibility of manufacturing FRP bridge decks with embedded fiber optic sensors.

  1. Applications of ground penetrating radar (GPR) in bridge deck monitoring and assessment

    NASA Astrophysics Data System (ADS)

    Alani, Amir M.; Aboutalebi, Morteza; Kilic, Gokhan

    2013-10-01

    This paper presents the essence of two case studies by the authors on two major bridges in the UK. The first case study reports on the applications of GPR and associated work carried out on the Forth Road Bridge near Edinburgh, Scotland, with the main objective of identifying possible structural defects including damaged rebar and moisture ingress at specific locations of the bridge deck. The second case study focuses on a full assessment of the Pentagon Road Bridge, in Chatham, Kent, England with particular emphasis on the identification of possible defects including structural cracks within the deck structure and establishing the layout of the upper and lower rebar positions throughout the bridge. These studies present interesting results in terms of locations of rebar and an accurate estimate of concrete cover condition as well as reporting on a remarkable similarity in the processed data concerning areas affected by ingress of moisture within the deck structures of the two bridges under investigation. It is believed that this paper will be of particular interest to bridge engineers and structural engineering practitioners with enthusiasm for adopting non-destructive testing methods such as GPR in the health monitoring and assessment of bridge structures. The observed similarities in the processed data between the two reported case studies present an interesting concept within the general context of the interpretation of GPR data, with the potential for use in many other forthcoming cases. The paper also reports on the adopted method for the GPR survey with emphasis on difficulties and challenges encountered during the actual survey. The presented results benefit from advanced processing and presentation techniques.

  2. Numerical simulations and experimental measurements of steel and ice impacts on concrete for acoustic interrogation of delaminations in bridge decks

    SciTech Connect

    Mazzeo, Brian A.; Patil, Anjali N.; Klis, Jeffrey M.; Hurd, Randy C.; Truscott, Tadd T.; Guthrie, W. Spencer

    2014-02-18

    Delaminations in bridge decks typically result from corrosion of the top mat of reinforcing steel, which leads to a localized separation of the concrete cover from the underlying concrete. Because delaminations cannot be detected using visual inspection, rapid, large-area interrogation methods are desired to characterize bridge decks without disruption to traffic, without the subjectivity inherent in existing methods, and with increased inspector safety. To this end, disposable impactors such as water droplets or ice chips can be dropped using automatic dispensers onto concrete surfaces to excite mechanical vibrations while acoustic responses can be recorded using air-coupled microphones. In this work, numerical simulations are used to characterize the flexural response of a model concrete bridge deck subject to both steel and ice impactors, and the results are compared with similar experiments performed in the laboratory on a partially delaminated concrete bridge deck slab. The simulations offer greater understanding of the kinetics of impacts and the responses of materials.

  3. Numerical simulations and experimental measurements of steel and ice impacts on concrete for acoustic interrogation of delaminations in bridge decks

    NASA Astrophysics Data System (ADS)

    Mazzeo, Brian A.; Patil, Anjali N.; Klis, Jeffrey M.; Hurd, Randy C.; Truscott, Tadd T.; Guthrie, W. Spencer

    2014-02-01

    Delaminations in bridge decks typically result from corrosion of the top mat of reinforcing steel, which leads to a localized separation of the concrete cover from the underlying concrete. Because delaminations cannot be detected using visual inspection, rapid, large-area interrogation methods are desired to characterize bridge decks without disruption to traffic, without the subjectivity inherent in existing methods, and with increased inspector safety. To this end, disposable impactors such as water droplets or ice chips can be dropped using automatic dispensers onto concrete surfaces to excite mechanical vibrations while acoustic responses can be recorded using air-coupled microphones. In this work, numerical simulations are used to characterize the flexural response of a model concrete bridge deck subject to both steel and ice impactors, and the results are compared with similar experiments performed in the laboratory on a partially delaminated concrete bridge deck slab. The simulations offer greater understanding of the kinetics of impacts and the responses of materials.

  4. An Automatic Impact-based Delamination Detection System for Concrete Bridge Decks

    SciTech Connect

    Zhang, Gang; Harichandran, Ronald S.; Ramuhalli, Pradeep

    2012-01-02

    Delamination of concrete bridge decks is a commonly observed distress in corrosive environments. In traditional acoustic inspection methods, delamination is assessed by the "hollowness" of the sound created by impacting the bridge deck with a hammer or bar or by dragging a chain where the signals are often contaminated by ambient traffic noise and the detection is highly subjective. In the proposed method, a modified version of independent component analysis (ICA) is used to filter the traffic noise. To eliminate subjectivity, Mel-frequency cepstral coefficients (MFCC) are used as features for detection and the delamination is detected by a radial basis function (RBF) neural network. Results from both experimental and field data suggest that the proposed methods id noise robust and has satisfactory performance. The methods can also detect the delamination of repair patches and concrete below the repair patches. The algorithms were incorporated into an automatic impact-bases delamination detection (AIDD) system for field application.

  5. Effective presentation of impact-echo data for bridge deck NDE

    NASA Astrophysics Data System (ADS)

    Oh, T.; Popovics, J. S.

    2014-02-01

    Air-Coupled Impact Echo (IE) test is a non-destructive evaluation (NDE) test method, where the dynamic response of an element resulting from an impact event is measured with an air-coupled sensor. IE has been used to characterize damage in concrete bridge decks in a rapid fashion. However, the large amount of data from air-coupled IE tests from bridge decks must be manipulated and presented such that infrastructure engineers can effectively assess the condition of the structure. To address this problem, we used both impact-echo and flexural mode vibrations to characterize the area and degree of delamination damage. The practical nature of this imaging approach is demonstrated experimentally with concrete slabs containing simulated delamination damage.

  6. Bridge deck repairs with polymer concrete patching materials

    NASA Astrophysics Data System (ADS)

    Edgecomb, W. C., Jr.

    1983-01-01

    The FHWA polymer concrete as formulated at Brookhaven National laboratory (BNL) was mixed, placed into spalls and finished on grade with steel trowels on more than a dozen bridges. This polymer concrete was a two-component system consisting of a liquid monomer component comprised of methyl methacrylate base, which contained a cross linking agent with promoters and an inhibitor, and a powder component which contained reactive polymers, blend of silica sands, initiator, and color pigments. These formed an impregnable material of approximately 8000 psi. Cure time for this project's cold weather formulation to obtain this strength was approximately 2 hours at 40 F.

  7. Experimental and theoretical evalution of infrared thermography for surveying the condition of bridge decks

    NASA Astrophysics Data System (ADS)

    Masliwec, T.

    1988-01-01

    A comprehensive data base is a critical component of a cost-effective bridge management program. Data is needed in order to assess the overall condition of the bridge network, establish priorities for repair, select the most appropriate methods for bridge repair, and prepare contract documents. The most practical and economic method of collecting this information is to use indirect measurement. techniques. Such non-destructive techniques do not directly measure the physical properties of the structure and the condition must be inferred using signal processing methods. A number of bridge testing techniques were investigated by the Ontario Ministry of Transportation over a period of almost ten years. The product of the studies is the Deck Assessment by Radar and Thermography (DART) system. As the acronym implies, DART utilises two basic systems: impulse radar and infrared thermography. This paper describes the main features of the DART infrared system. A theoretical two-dimensional heat transfer model for estimating temperature profiles in bridge decks is also presented. Actual temperature measurements are provided for comparison with the theoretical model.

  8. Application of ultrasonic surface wave techniques for concrete bridge deck condition assessment

    NASA Astrophysics Data System (ADS)

    Li, Mengxing; Anderson, Neil; Sneed, Lesley; Maerz, Norbert

    2016-03-01

    Ultrasonic surface wave (USW) is a well-established technique for the performance monitoring of concrete structures. In order to investigate the capability and reliability of this technique for concrete bridge deck condition assessment, a portable seismic property analyzer (PSPA) with USW capabilities was used to assess the condition of a reinforced concrete bridge deck exhibiting visible evidence of significant deterioration. After the investigation was completed, variable thicknesses of concrete were removed from upper surface of the concrete deck by milling and hydrodemolition, with greater thickness being removed where the concrete was more deteriorated. The thickness of removed concrete during the hydrodemolition process was mapped by Light Detection and Ranging (LiDAR). A comparison of the thickness of concrete removed and the USW data indicates that there is a qualitative correlation between the USW results at each test location and the thickness of concrete removed at those same test locations. Results suggest that the PSPA, and comparable USW techniques, could be potentially effective for estimating the thicknesses of concrete that would be removed during milling and hydrodemolition, although more work is needed to study the relationship between USW and removal thickness data in order to be used for quantity estimations.

  9. Implementation of civionics in a second generation steel-free bridge deck

    NASA Astrophysics Data System (ADS)

    Klowak, Chad; Rivera, Evangeline; Mufti, Aftab

    2005-05-01

    As the design and construction of civil structures continue to evolve, it is becoming imperative that these structures be monitored for their health. In order to meet this need, the discipline of Civionics has emerged. Civionics is a new term coined from Civil-Electronics, which is derived from the application of electronics to civil structures. It is similar to the term Avionics, which is used in the aerospace industry. If structural health monitoring is to become part of civil structural engineering, it should include Civionics. It involves the application of electronics to civil structures and aims to assist engineers in realizing the full benefits of structural health monitoring (SHM). In past SHM field applications, the main reason for the failure of a sensor was not the installation of the sensor itself but the egress of the sensor cables. Often, the cables were not handled and protected correctly. For SHM to be successful, specifications must be written on the entire process, beginning with system design and concluding with data collection, interpretation, and management. Civionics specifications include the technical requirements for a SHM system which encompasses fibre optic sensors, cables, conduits, junction boxes and the control room. A specification for data collection and storage is currently being developed as well. In the spring of 2004 research engineers at the University of Manitoba constructed a full-scale second generation steel free bridge deck. The bridge deck is the first of its kind to fully incorporate a complete civionics structural health monitoring system to monitor the deck's behaviour during destructive testing. Throughout the construction of the bridge deck, the entire installation of the civionics system was carried out by research engineers simulating an actual implementation of such a system in a large scale construction environment. One major concern that consulting engineers have raised is the impact that a civionics system that uses conduit, junction boxes, and other electrical ancillary protection, will have when embedded and installed externally on full-scale infrastructure. The full-scale destructive testing of a second generation steel-free bridge deck using a civionics system designed and implemented following guidelines in a civioncs specification manual at the University of Manitoba will provide engineers with the information necessary to address the constructability and structural integrity issues. Civioncs combined with structural health monitoring will provide engineers with feedback necessary to aid in optimizing design techniques and understanding our infrastructures performance, behaviour and state of condition.

  10. Biaxial Behavior of Ultra-High Performance Concrete and Untreated UHPC Waffle Slab Bridge Deck Design and Testing

    NASA Astrophysics Data System (ADS)

    D'Alessandro, Kacie Caple

    Ultra-high performance concrete (UHPC) was evaluated as a potential material for future bridge deck designs. Material characterization tests took place to identify potential challenges in mixing, placing, and curing UHPC. Biaxial testing was performed to evaluate behavior of UHPC in combined tension and compression stress states. A UHPC bridge deck was designed to perform similarly to a conventional concrete bridge deck, and a single unit bridge deck section was tested to evaluate the design methods used for untreated UHPC. Material tests identified challenges with placing UHPC. A specified compressive strength was determined for structural design using untreated UHPC, which was identified as a cost-effective alternative to steam treated UHPC. UHPC was tested in biaxial tension-compression stress states. A biaxial test method was developed for UHPC to directly apply tension and compression. The influence of both curing method and fiber orientation were evaluated. The failure envelope developed for untreated UHPC with random fiber orientation was suggested as a conservative estimate for future analysis of UHPC. Digital image correlation was also evaluated as a means to estimate surface strains of UHPC, and recommendations are provided to improve consistency in future tests using DIC methods. A preliminary bridge deck design was completed for untreated UHPC and using established material models. Prestressing steel was used as primary reinforcement in the transverse direction. Preliminary testing was used to evaluate three different placement scenarios, and results showed that fiber settling was a potential placement problem resulting in reduced tensile strength. The UHPC bridge deck was redesigned to incorporate preliminary test results, and two single unit bridge deck sections were tested to evaluate the incorporated design methods for both upside down and right-side up placement techniques. Test results showed that the applied design methods would be conservative for either placement method.

  11. Real Time Detection of Defects in GFRP Bridge Decks Using Infrared Thermography

    NASA Astrophysics Data System (ADS)

    Klinkhachorn, P.; Lonkar, G. M.; Halabe, Udaya B.; GangaRao, Hota V. S.

    2006-03-01

    This work is aimed at building a real time system to detect subsurface defects in GFRP bridge decks using infrared thermography. The issues addressed are: (a) development of a real time defect detection system, and (b) image mosaicking to build a composite image map. In the tests conducted, a turn key system was built in Matlab environment using the FLIR SDK to acquire image from the ThermaCAM S60 infrared camera. The images were then analyzed by defect detection algorithms. Efforts were made to minimize the time to detect defects in a captured image. In the second phase, image mosaicking was used to build a "composite image" that combines all the infrared images to form a single image. The location of defects in the "composite image" leads to a system that will be able to point out defects in the bridge as a whole. The study creates a base that can be used for real time defect detection in GFRP bridge decks.

  12. Deck and Cable Dynamic Testing of a Single-span Bridge Using Radar Interferometry and Videometry Measurements

    NASA Astrophysics Data System (ADS)

    Piniotis, George; Gikas, Vassilis; Mpimis, Thanassis; Perakis, Harris

    2016-03-01

    This paper presents the dynamic testing of a roadway, single-span, cable-stayed bridge for a sequence of static load and ambient vibration monitoring scenarios. Deck movements were captured along both sideways of the bridge using a Digital Image Correlation (DIC) and a Ground-based Microwave Interfererometer (GBMI) system. Cable vibrations were measured at a single point location on each of the six cables using the GBMI technique. Dynamic testing involves three types of analyses; firstly, vibration analysis and modal parameter estimation (i. e., natural frequencies and modal shapes) of the deck using the combined DIC and GBMI measurements. Secondly, dynamic testing of the cables is performed through vibration analysis and experimental computation of their tension forces. Thirdly, the mechanism of cable-deck dynamic interaction is studied through their Power Spectra Density (PSD) and the Short Time Fourier Transform (STFT) analyses. Thereby, the global (deck and cable) and local (either deck or cable) bridge modes are identified, serving a concrete benchmark of the current state of the bridge for studying the evolution of its structural performance in the future. The level of synergy and complementarity between the GBMI and DIC techniques for bridge monitoring is also examined and assessed.

  13. Data acquisition and processing parameters for concrete bridge deck condition assessment using ground-coupled ground penetrating radar: Some considerations

    NASA Astrophysics Data System (ADS)

    Varnavina, Aleksandra V.; Khamzin, Aleksey K.; Torgashov, Evgeniy V.; Sneed, Lesley H.; Goodwin, Brandon T.; Anderson, Neil L.

    2015-03-01

    Ground penetrating radar (GPR) is a non-destructive geophysical technique that is widely used to determine the relative condition of reinforced concrete. This paper presents case studies from Missouri, USA, where a ground-coupled GPR system was used to assess the condition of eleven concrete bridge decks. The main goal of this paper is to develop appropriate acquisition and processing parameters in order to conduct rapid, efficient, and cost-effective assessment of bridge decks. To accomplish this goal, the GPR data sets were collected with slightly different acquisition parameters and processed using different parameters. The quality of the results and the time required for each bridge deck survey are analyzed. Additionally, several experimental data sets were collected across a 12th concrete bridge deck to examine the influence of weather conditions on reflection amplitude values, since amplitude analysis is used in this study. Based on the authors' experience and findings, appropriate GPR acquisition and processing parameters are suggested and described for use of the ground-coupled GPR method for bridge deck assessment.

  14. Effective visualization of impact-echo data for bridge deck NDE

    NASA Astrophysics Data System (ADS)

    Popovics, J. S.; Oh, T.; Ham, S.

    2012-05-01

    The large amount of data from air-coupled impact-echo tests from bridge decks must be manipulated and presented such that infrastructure engineers can effectively visualize the condition of the structure. To address this problem, we present the data in the form of "4-dimensional" images, which indicate the location of concrete delamination defects using air-coupled impact-echo data. The basis of the 4-D plot is introduced, and the effects of image parameter variation, such as frequency range and transparency index, are studied and experimentally confirmed.

  15. Ground-penetrating imaging radar development for bridge deck and road bed inspection

    SciTech Connect

    Warhus, J.P.; Mast, J.E.; Nelson, S.D.; Johansson, E.M.

    1993-05-01

    Ground-penetrating imaging radar (GPIR) is proposed for large-area inspection of concrete and concrete/asphalt composite bridge decks and roadways. This technique combines ground-penetrating radar (GPR) with unique image reconstruction algorithms developed for identification and characterization of subsurface flaws and structural features. New data acquisition hardware and image reconstruction techniques, under development at LLNL, offer the possibility for reliable and efficient, high-resolution subsurface imaging through the use of improved ultra-wideband transmitters, antennas, and arrays, and enhanced image- and signal-processing software. A field test of a limited-capability prototype system is planned for FY-93, as is completion of a conceptual design for a practical inspection system. A follow-on program for FY-94 would focus on development and demonstration of an advanced bridge inspection system prototype based on the conceptual design completed during FY-93.

  16. Detection of Delamination in Concrete Bridge Decks Using Mfcc of Acoustic Impact Signals

    NASA Astrophysics Data System (ADS)

    Zhang, G.; Harichandran, R. S.; Ramuhalli, P.

    2010-02-01

    Delamination of the concrete cover is a commonly observed damage in concrete bridge decks. The delamination is typically initiated by corrosion of the upper reinforcing bars and promoted by freeze-thaw cycling and traffic loading. The detection of delamination is important for bridge maintenance and acoustic non-destructive evaluation (NDE) is widely used due to its low cost, speed, and easy implementation. In traditional acoustic approaches, the inspector sounds the surface of the deck by impacting it with a hammer or bar, or by dragging a chain, and assesses delamination by the "hollowness" of the sound. The detection of the delamination is subjective and requires extensive training. To improve performance, this paper proposes an objective method for delamination detection. In this method, mel-frequency cepstral coefficients (MFCC) of the signal are extracted. Some MFCC are then selected as features for detection purposes using a mutual information criterion. Finally, the selected features are used to train a classifier which is subsequently used for detection. In this work, a simple quadratic Bayesian classifier is used. Different numbers of features are used to compare the performance of the detection method. The results show that the performance first increases with the number of features, but then decreases after an optimal value. The optimal number of features based on the recorded signals is four, and the mean error rate is only 3.3% when four features are used. Therefore, the proposed algorithm has sufficient accuracy to be used in field detection.

  17. Epoxy-coated-rebar performance in the deck of the Perley Bridge

    SciTech Connect

    Covino, Bernard S., Jr.; Cramer, Stephen D.; Holcomb, Gordon R.; Russell, James H.; Bullard, Sophie J.; Dahlin, Cheryl L.; Tinnea, John S.

    2001-01-01

    The Perley Bridge spans the Ottawa River between the Canadian provinces of Ontario and Quebec. During a 1979 rehabilitation project, epoxy-coated rebar (ECR) was installed in an effort to extend the service life of span 17. External signs of corrosion were observed in the west lane of span 17 as early as 1985, but none were observed in the east lane. The cover concrete on the east lane was almost twice that of the west lane. A wide variety of techniques were used to evaluate the difference between slabs cut from the east and west lanes. The most useful techniques were potential mapping, chloride profiling, petrographic analyses, adhesion testing, epoxy damage, analyses of reinforcing bar-concrete crosssections, and electrochemical impedance spectroscopy measurements of epoxy properties. Cover depth and chloride contamination were the most significant factors affecting damage to the rebar. Based on these techniques, results showed that the epoxy coating used on the west lane of the Perley Bridge deck in span 17 provided only 1 to 4 years of additional corrosion protection over bare rebar.

  18. Plans: Aft Gun Platform, Quarters for 16 Gunmen, Poop Deck, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Plans: Aft Gun Platform, Quarters for 16 Gunmen, Poop Deck, Boat Deck, House Top, Bridge Deck, Upper Bridge Deck, Navigating Bridge, Forecastle Deck, Gun Platform, Upper Deck, Second Deck and Hold Plan - Mission Santa Ynez, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  19. Multi-mode traffic-induced vibrations in composite ladder-deck bridges under heavy moving vehicles

    NASA Astrophysics Data System (ADS)

    Camara, A.; Ruiz-Teran, A. M.

    2015-10-01

    Composite (steel-concrete) ladder-decks represent one of the most common solutions in road bridges nowadays. In these structures the Serviceability Limit State (SLS) of vibrations is traditionally ignored or roughly addressed by means of simple static deflection-based approaches, inherently assuming that the vibrations are controlled by the fundamental longitudinal mode. This work demonstrates that a wide range of high-order vibrational modes, involving the transverse flexure of the slab between longitudinal girders, govern the accelerations recorded in the deck and inside the vehicles. In addition, a new methodology for analysing the Vehicle-Bridge Interaction is proposed, including the approaching platforms, the transition slabs, and the bridge joints. The results suggest that the riding comfort for vehicle users is specially affected by direct effects on the wheels, like the road roughness and possible construction misalignments at the bridge joints, as well as low-frequency vibrations coming from the deck in short or slender bridges. The filtering effects resulting from the average of the response in time and in space when calculating the root mean square acceleration are also explored, and new design parameters are provided. In addition, several structural features (such as the depth and spacing of the longitudinal and transverse steel beams, the thickness of the concrete slab, and the stiffness of the cantilever cross beams at the diaphragm sections) have been studied, and a set of new design criteria has been established. It has been demonstrated that the transverse flexibility of the deck (specially influenced by the support conditions and the slab thickness) is critically important for the users' (pedestrians and vehicle passengers) comfort, as it controls the aforementioned high-order vibrational modes which govern the dynamic response.

  20. Application of Noise Cancelling and Damage Detection Algorithms in NDE of Concrete Bridge Decks Using Impact Signals

    SciTech Connect

    Zhang, Gang; Harichandran, Ronald S.; Ramuhalli, Pradeep

    2011-09-13

    Delamination is a commonly observed distress in concrete bridge decks. Among all the delamination detection methods, acoustic methods have the advantages of being fast and inexpensive. In traditional acoustic inspection methods, the inspector drags a chain along or hammers on the bridge deck and detects delamination from the 'hollowness' of the sounds. The signals are often contaminated by ambient traffic noise and the detection of delamination is highly subjective. This paper describes the performance of an impact-bases acoustic NDE method where the traffic noise was filtered by employing a noise cancelling algorithm and where subjectivity was eliminated by introducing feature extraction and pattern recognition algorithms. Different algorithms were compared and the best one was selected in each category. The comparison showed that the modified independent component analysis (ICA) algorithm was most effective in cancelling the traffic noise and features consisting of mel-frequency cepstral coefficients (MFCCs) had the best performance in terms of repeatability and separabillty. The condition of the bridge deck was then detected by a radial basis function (RBF) neural network. The performance of the system was evaluated using both experimental and field data. The results show that the selected algorithms increase the noise robustness of acoustic methods and perform satisfactorily if the training data is representative.

  1. Performance of epoxy-coated reinforced steel in the deck of the Perley Bridge

    SciTech Connect

    Covino, Bernard S., Jr.; Cramer, Stephen D.; Holcomb, Gordon R.; Russell, James H.; Bullard, Sophie J.; Dahlin, Cheryl L.; Tinnea, J.S.

    2001-01-01

    The Perley Bridge spanned the Ottawa River between the Canadian provinces of Ontario and Quebec from 1931 to 1999. Epoxy-coated steel reinforcing bar (ECR) was used in 1979 in an effort to extend the service life of span 17. Patches were needed to repair corrosion of the west lane as little as 7 to 11 years later. No patches were needed for the east lane which had twice the cover concrete of the west lane. Examinations showed that the original concrete in both lanes and the patch concrete in the west lane were of good quality. Epoxy adhesion to the steel reinforcing bar was good to fair over much of the reinforcing bar, but poor to failed in isolated areas. Analytical scanning electron microscopy (ASEM) identified voids, rust, cracked epoxy, and cracked concrete at some ECR locations. Chloride profiling of the concrete in both lanes, coupled with the corrosion threshold level of chloride, indicated that the time required for corrosion to cause visible damage of the deck was 6.2 years for the west lane and 18.9 years for the east lane.

  2. Plans: 3'/50 Cal. Gun Platform, Boat Deck House Top & ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Plans: 3'/50 Cal. Gun Platform, Boat Deck House Top & Fidley Top, Boat Deck, Radar Platform Lower, Pilot House Top, Navigation Bridge, Upper Bridge Deck, Poop Deck, Cargo Deck, Motor Boat Platform, Bridge Deck, Forecastle Deck, Upper Deck - Taluga, Suisun Bay Reserve Fleet, Benicia, Solano County, CA

  3. Ground penetrating radar and microwave tomography 3D applications for the deck evaluation of the Musmeci bridge in Potenza, Italy

    NASA Astrophysics Data System (ADS)

    Bavusi, Massimo; Soldovieri, Francesco; Di Napoli, Rosario; Loperte, Antonio; Di Cesare, Antonio; Carlo Ponzo, Felice; Lapenna, Vincenzo

    2011-09-01

    An extensive experimental and numerical investigation has been carried out to assess the status of the 'Ponte sul Basento' (1967-1976), in the town of Potenza (Basilicata region, southern Italy), better known as the Musmeci bridge. Architecturally, the bridge is a considerable reinforced 20th century concrete structure that was designed and built by the Italian architect Sergio Musmeci (1926-1981). Moreover, the bridge represents an important element of the infrastructural network, linking the city centre to the Potenza-Sicignano highway, crossing the Basento river and the railway close to the main train station of the city. Recently, due to ageing and continuous and significant traffic, the bridge started to be affected by several problems such as water infiltration. Within the presented study, a widespread ground penetrating radar (GPR) survey has been designed to investigate the geometrical characteristics of the bridge deck (Gerber saddles, internal stiffening walls, pillar supports) and detect the presence of defects or damage due to water infiltration and traffic fatigue. Concerning this, a 900 MHz 3D GPR survey has been performed along a zone of one of the lanes on the road surface. Moreover, a second 1500 MHz 3D survey has been carried out at the bottom of the bridge deck in order to gain detailed information about an important structural element of the bridge, the Gerber saddle. Both results have been processed following two approaches: the first a classical time-domain processing session based on commercial software and the use of migration; the second in microwave tomography, an advanced frequency domain automatic PC-based inversion algorithm. In this paper, we present a comparative interpretation of both kinds of processed results, and provide considerations about the investigated structures.

  4. Groove depth requirements for tine-textured rigid pavement 5: Durability of tine texturing on PCC pavements

    NASA Astrophysics Data System (ADS)

    Grady, J. E.; Chamberlin, W. P.

    1981-06-01

    The required depth for grooves on new tine textured concrete pavements in order to assure an adequate skid resistance over their entire design life is discussed. Measurements of texture depth and skid resistance, with both ribbed and smooth tires were made on 0 to 5 year-old New York pavements. Initial groove depth needs of 3/16 in. minimum were calculated from two values estimated from the study data: the minimum depth (0.050 in.) to assure adequate skid resistance with a minimally legal treaded tire, and the mean groove wear rate (0.013 in./million vehicle passes). Groove depth measurements on new concrete pavements and bridge decks indicated 21 an 14 percent compliance, respectively, with the proposed new standard of 3/16 in. minimum, and 60 and 44 percent compliance with the current standard of 2/16 in. minimum.

  5. Examination of Single- and Multi-Channel GPR Bridge Deck Condition Assessment Methods with Comparison to Complementary NDE Results

    NASA Astrophysics Data System (ADS)

    Romero, Francisco A.; Manacorda, Guido; Simi, Alessandro; Gucunski, Nenad; Parvardeh, Hooman

    2013-04-01

    A sixteen-channel GPR system which houses both longitudinally- and transversely-polarized, 2.0 GHz antenna elements within a single housing was compared with a single-channel GPR system that was separately using both 1.5GHz and 2.6GHz antennas oriented in the transverse polarization, for the purpose of determining effectiveness of bridge deck condition assessment. The multi-channel system has obvious benefits which include closely-spaced GPR antennas (channels) that provide better lateral resolution, as well as combined data sets from co-linear antennas oriented in both the transverse and longitudinal polarizations, which has benefits for imaging within the deck's internal structure. However, the primary objective was to determine whether the multi-channel system would perform in a similar manner to proven single-channel GPR technology during an attenuation-based GPR condition assessment on an older, partially deteriorated deck in northwestern New Jersey that is annually exposed to freeze-thaw conditions as well as de-icing salts. These assessments were made by focusing on identifying the strongest reflections from the upper mat of transversely-oriented rebars within the deck and comparing reflection strength, or conversely, attenuation of the GPR signal, from each of the 'picked' GPR rebar responses. Coordinates for each of the GPR picks, along with amplitude or attenuation measurements, were gridded and contour-plotted for the purpose of identifying areas identified as either relatively deteriorated or sound. Initially, results were compared for data with no applied correction that takes into account GPR signal attenuation with increasing depth within the concrete deck. Final GPR maps were produced incorporating a depth-correction technique similar to what is described by Barnes, et. al., Romero, et. al, and Gucunski, et. al., a process which has been clearly demonstrated to better correlate GPR results with not only ground truth (cores, sounding) but also with other NDE technologies. Not only did all the single- and multi-channel system comparisons generate nearly identical deterioration maps when GPR results were compared and examined, but mapped results obtained from other NDE methods on the same deck were used to identify zones where corrosive environment (electrical resistivity - ER) elastic modulus (ultrasonic surface wave - USW), and identified delaminations (impact-echo - IE) had commonality with the GPR results. A summary of the equipment used, as well as general data collection and analysis procedures is provided for the GPR condition assessments. Brief descriptions of background and references to how the complementary NDT technologies are deployed, and how data are interpreted, are also discussed. Comparative maps for all technologies are used for illustrative purposes.

  6. Development and construction of low-cracking high-performance concrete (LC-HPC) bridge decks: Free shrinkage tests, restrained ring tests, construction experience, and crack survey results

    NASA Astrophysics Data System (ADS)

    Yuan, Jiqiu

    2011-12-01

    The development, construction, and evaluation of low-cracking high-performance concrete (LC-HPC) bridge decks are described based on laboratory test results and experiences gained during the construction of 13 LC-HPC bridge decks in Kansas, along with another deck bid under the LC-HPC specifications but for which the owner did not enforce the specification. This study is divided into four parts covering (1) an evaluation of the free shrinkage properties of LC-HPC candidate mixtures, (2) an investigation of the relationship between the evaporable water content in the cement paste and the free shrinkage of concrete, (3) a study of the restrained shrinkage performance of concrete using restrained ring tests, and (4) a description of the construction and preliminary evaluation of LC-HPC and control bridge decks constructed in Kansas. The first portion of the study involves evaluating the effects of the duration of curing, fly ash, and a shrinkage reducing admixture (SRA) on the free-shrinkage characteristics of concrete mixtures. The results indicate that an increase of curing period reduces free shrinkage. With 7 days of curing, concretes containing fly ash as a partial replacement for cement exhibit higher free shrinkage than concretes with 100% portland cement. When the curing period is increased to 14, 28, and 56 days, the adverse effect of adding fly ash on free shrinkage is minimized and finally reversed. The addition of an SRA significantly reduces free shrinkage for both the 100% portland cement mixture and the mixture containing fly ash. The second portion of the study investigates the relationship between the evaporable water content in the cement paste and the free shrinkage of concrete. A linear relationship between free shrinkage and evaporable water content in the cement paste is observed. For a given mixture, specimens cured for a longer period contain less evaporable water and exhibit lower free shrinkage and less weight loss in the free shrinkage specimens than those cured for a shorter period. The third portion of the study evaluates the cracking tendency of concrete mixtures using the restrained ring tests. Different concrete ring thicknesses and drying conditions have been tested. The results indicate that specimens with thinner concrete rings crack earlier than those with thicker concrete rings. Exposing specimens to severe drying conditions results in the earlier formation of cracks, although it does not result in increased crack width. Mixtures with a lower water-cement (w/c) ratio crack earlier than mixtures with a higher w/c ratio. Concretes with a higher paste content crack earlier than concretes with a lower paste content. The final portion of the study details the development, construction, and preliminary performance (with most bridges at three years of age) of LC-HPC and control bridge decks in Kansas. The results indicate that the techniques embodied in the LC-HPC bridge deck specifications are easy to learn. Contractor personnel can be trained in a relatively short time. The techniques used for LC-HPC bridge decks are effective in reducing bridge deck cracking. The crack surveys indicate that LC-HPC bridge decks are performing much better than the control decks, with average crack densities reduced by about seventy five percent at three years of age. The factors that may affect bridge deck cracking are analyzed. The analyses indicate that an increase in paste content, slump, compressive strength, maximum daily air temperature, and daily air temperature range causes increased crack densities. Contractor techniques influence cracking. Keywords: bridge construction, bridge deck, contractor, concrete mix design, compressive strength, cracking, curing, evaporable water, fly ash, free shrinkage, high-performance concrete, non-evaporable water, paste content, restrained shrinkage, restrained ring tests, shrinkage reducing admixture, slump

  7. 19. view from below deck showing Pier 2, deck stringers, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. view from below deck showing Pier 2, deck stringers, railing, counterweight and superstructure. VIEW WEST - Chelsea Street Bridge & Draw Tender's House, Spanning Chelsea River, Boston, Suffolk County, MA

  8. A Methodology to Assess the Degradation in the Structural Response of the Deck of a Reinforced Concrete Road Bridge due to Corrosion of Reinforcing Steel

    NASA Astrophysics Data System (ADS)

    Banerjee, Soumendra; Sengupta, Amlan K.

    2012-02-01

    The present paper provides a methodology to analyse the effect of corrosion on the strength and stiffness of the slab-and-girder deck of a road bridge. A linear finite element model of a typical medium span deck of an existing bridge was developed as per the as-built drawings. The vehicular loadings were as per the recommendations of the Indian Roads Congress specifications and the design rating of the bridge. Based on the phenomenon of corrosion, a time-dependent reduction in the area of flexural reinforcement near the soffits of the girders, was considered in the model. The effects of flexural cracking, creep and spalling of concrete were incorporated in the model with non-prismatic section properties and their stage-wise variations. From the analyses of a girder section and the computational model, it was observed that due to corrosion, the allowable moment capacity of a girder falls below the demand under dead load plus the rated live load, within the target service life of the bridge. However, the effect of corrosion on the stiffness of the deck is not substantial to be accurately measured by a conventional sensor. It is recommended that the procedure adopted in the paper can be used by the practicing professionals for numerically assessing longer span decks, to have a'priori estimates of the quantities that can be measured in a field test.

  9. Bridge deck surface temperature monitoring by infrared thermography and inner structure identification using PPT and PCT analysis methods

    NASA Astrophysics Data System (ADS)

    Dumoulin, Jean

    2013-04-01

    One of the objectives of ISTIMES project was to evaluate the potentialities offered by the integration of different electromagnetic techniques able to perform non-invasive diagnostics for surveillance and monitoring of transport infrastructures. Among the EM methods investigated, we focused our research and development efforts on uncooled infrared camera techniques due to their promising potential level of dissemination linked to their relative low cost on the market. On the other hand, works were also carried out to identify well adapted implementation protocols and key limits of Pulse Phase Thermography (PPT) and Principal Component Thermography (PCT) processing methods to analyse thermal image sequence and retrieve information about the inner structure. So the first part of this research works addresses infrared thermography measurement when it is used in quantitative mode (not in laboratory conditions) and not in qualitative mode (vision applied to survey). In such context, it requires to process in real time thermal radiative corrections on raw data acquired to take into account influences of natural environment evolution with time, thanks to additional measurements. But, camera sensor has to be enough smart to apply in real time calibration law and radiometric corrections in a varying atmosphere. So, a complete measurement system was studied and developed [1] with low cost infrared cameras available on the market. In the system developed, infrared camera is coupled with other sensors to feed simplified radiative models running, in real time, on GPU available on small PC. The whole measurement system was implemented on the "Musmeci" bridge located in Potenza (Italy). No traffic interruption was required during the mounting of our measurement system. The infrared camera was fixed on top of a mast at 6 m elevation from the surface of the bridge deck. A small weather station was added on the same mast at 1 m under the camera. A GPS antenna was also fixed at the basis of the mast and at a same elevation than the bridge deck surface. This trial took place during 4 days, but our system was leaved in stand alone acquisition mode only during 3 days. Thanks to the software developed and the small computer hardware used, thermal image were acquired at a frame rate of 0.1 Hz by averaging 50 thermal images leaving the original camera frame rate fixed at 5 Hz. Each hour, a thermal image sequence was stored on the internal hard drive and data were also retrieved, on demand, by using a wireless connection and a tablet PC. In the second part of this work, thermal image sequences analysis was carried out. Two analysis approaches were studied: one based on the use of the Fast Fourier Transform [2] and the second one based on the Principal Component Analysis [3-4]. Results obtained show that the inner structure of the deck was identified though thermal images were affected by the fact that the bridge was open to traffic during the whole experiments duration. ACKNOWLEDGEMENT - The research leading to these results has received funding from the European Community's Seventh Framework Programme (FP7/2007-2013) under Grant Agreement n° 225663. References [1] Dumoulin J. and Averty R., « Development of an infrared system coupled with a weather station for real time atmospheric corrections using GPU computing: Application to bridge monitoring", QIRT 2012, Naples, Italy, June 2012. [2] Cooley J.W., Tukey J.W., "An algorithm for the machine calculation of complex Fourier series", Mathematics of Computation, vol. 19, n° 90, 1965, p. 297-301. [3] Rajic N., "Principal component thermography for flaw contrast enhancement and flaw depth characterization in composite structures", Composite Structures, vol 58, pp 521-528, 2002. [4] Marinetti S., Grinzato E., Bison P. G., Bozzi E., Chimenti M., Pieri G. and Salvetti O. "Statistical analysis of IR thermographic sequences by PCA," Infrared Physics & Technology vol 46 pp 85-91, 2004.

  10. Seismic Integrity of a Long Span Bridge with Tower-Deck Buffers

    SciTech Connect

    Casciati, Fabio; Giuliano, Fabio

    2008-07-08

    The wind action is acknowledged to be the primary environmental load in the design of suspension bridges. It affects both the performance of safety and serviceability. Nevertheless, the impact of earthquakes cannot be neglected especially when the construction site is located in a high seismicity region. The evaluation of the vulnerability of a suspension bridge requires a hazard analysis on the site, the definition of the seismic intensity related to the desired return periods, the generation of artificial signals for the reference site and the collection of critical records for integrity analyses,. The signals will then be used in the structural analyses for the verification of structural safety and structural robustness. This paper is focused on the generation of these critical signals, with their own a-synchronicity, and the associated numerical nonlinear analyses, which must be conducted in the time domain.

  11. 7. DETAIL OF DECK TRUSS SPANNING CANAL. THIS DECK TRUSS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL OF DECK TRUSS SPANNING CANAL. THIS DECK TRUSS WA ALSO ERECTED IN 1893 AS PART OF AN EXTENSIVE RECONSTRUCTION OF THE BRIDGE. LOOKING NORTHEAST FROM SOUTH SIDE OF CANAL. - Illinois Central Railroad, Illinois River Bridge, Spanning Illinois River, La Salle, La Salle County, IL

  12. HERMES: a high-speed radar imaging system for inspection of bridge decks

    SciTech Connect

    Azevedo, S.G.

    1996-10-26

    Corrosion of rebar in concrete bridges causes subsurface cracks and is a major cause of structural degradation that necessitates repair or replacement. Early detection of corrosion effects can limit the location and extent of necessary repairs, while providing long-term information about the infrastructure status. Most current detection methods, however, are destructive of the road surface and require closing or restricting traffic while the tests are performed. A ground-penetrating radar imaging system has been designed and developed that will perform the nondestructive evaluation of road-bed cracking at traffic speeds; i.e., without the need to restrict traffic flow. The first-generation system (called the HERMES bridge inspector), consists of an offset-linear array of 64 impulse radar transceivers and associated electronics housed in a trailer. Computers in the trailer and in the towing vehicle control the data acquisition, processing, and display. Cross-road resolution is three centimeters at up to 30 cm in depth, while down-road resolution depends on speed; 3 cm below 20 mph up to 8 cm at 50 mph. A two-meter- wide path is inspected on each pass over the roadway. This paper, describes the design of this system, shows preliminary results, and lays out its deployment schedule.

  13. 37. HANGAR FROM RAILROAD DECK TELESCOPED IN COLUMN & SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. HANGAR FROM RAILROAD DECK TELESCOPED IN COLUMN & SHOWING PIN WHICH TRANSFERS LOAD FROM RAILROAD DECK TO TRUSS WHEN IN DOWN POSITION - Armour, Swift, Burlington Bridge, Kansas City, Jackson County, MO

  14. 17. DRAWING NO. 14 TITLED 'WIND BRACING FOR LOWER DECK,' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DRAWING NO. 14 TITLED 'WIND BRACING FOR LOWER DECK,' DATED APRIL 15, 1903 - Mahoning Avenue Pratt Double-Deck Bridge, Spanning Mill Creek at Mahoning Avenue (C.R. 319), Youngstown, Mahoning County, OH

  15. 15. DETAIL, UNDERSIDE OF DECK, FROM BELOW AND WEST, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAIL, UNDERSIDE OF DECK, FROM BELOW AND WEST, SHOWING STRUCTURAL CONFIGURATION, INCLUDING FLOOR BEAMS, STRINGERS, BRACING, AND STEEL MESH DECK - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  16. Flying blind: designing and maintaining jointed concrete pavement without monitoring pavement pressure generation

    NASA Astrophysics Data System (ADS)

    Burke, Martin P., Jr.

    2001-08-01

    The generation of longitudinal pavement pressures or growth of jointed-rigid pavement have been recognized by many engineers for at least a century. The manifestations of this pressure/growth phenomenon, in the form of progressive pavement and bridge damage, are vivid examples of its destructive potential. Yet, only a few researchers have attempted to measure the pressures generated by this phenomenon. None, to the author's knowledge, have attempted to periodically monitor pressure generation for the purpose of either determining and describing pressure generation characteristics or predicting the probability of its abrupt final and destructive manifestations. Because the pavement/growth phenomenon occurs over such a long period of time (a decade or more), it is generally unrecognized, or if recognized, it is poorly understood. Consequently, design and maintenance of jointed rigid pavement continues to be guided more by intuition and personal judgement rather than be replicated research and professional consensus. This paper provides a speculative description of the pavement pressure/growth phenomenon. It also contains an appeal to research professionals to develop instrumentation suitable to monitor generating pavement pressures. The results of such research should finally enable the transportation profession to establish suitable background so that future pavement design and maintenance will be guided so that pressure generation will be minimized and pavement and bridge function and durability will be improved. Otherwise, transportation systems will continue to experience progressive and substantial pavement and bridge damage, commensurate repair costs, and the traveling public will continue to be exposed to occasional but abrupt manifestations of its destructive potential.

  17. Bridges

    USGS Multimedia Gallery

    Bridges from top to bottom: Expressway Bridge, Liberty Memorial Bridge, Burlington Northern SantaFe Railway Bridge, and Interstate 94 Grant Marsh Bridge. Photo taken by USGS personnel on a Civil Air Patrol flight....

  18. SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN vSHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN SHARP OBLIQUE PERSPECTIVE OF DECK AND APPROACH SPANS ALONG WITH PRINCIPLE CANTILEVER SPAN - Snake River Bridge at Lyons' Ferry, State Route 261 spanning Snake River, Starbuck, Columbia County, WA

  19. 5. DETAIL OF TRUSS MEMBERS, GUARDRAIL AND DECK TO Georgia ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. DETAIL OF TRUSS MEMBERS, GUARDRAIL AND DECK TO Georgia DOT BRIDGE No. 105-00168X-00203E - Georgia DOT Bridge No. 105-00168X-00203E, Spanning Beaverdam Creek at County Road 168, Elberton, Elbert County, GA

  20. Structural improvement of strengthened deck panels with externally bonded plates

    SciTech Connect

    Sim, Jongsung; Oh, Hongseob . E-mail: opera69@chollian.net

    2005-07-01

    Concrete bridge decks require eventual replacement and rehabilitation due to decreasing load-carrying capacity. This paper compares different strengthening design procedures that improve the usability and structural performance of bridge decks. The failure characteristics of bridge decks strengthened with various materials such as carbon fiber sheet, glass fiber sheet, steel plate, and grid CFRP and GFRP are analyzed, and the theoretical load-carrying capacities are evaluated using traditional beam and yield line theory, and punching shear analysis. The strengthening materials increase the punching shear strength of the deck and change the failure mode of the strengthened panel.

  1. 11. Standing on westerly fender at edge of bridge looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Standing on westerly fender at edge of bridge looking easterly, showing horizontal beams for deck and cross beams (reflection of steel grating on deck). Also shows bridge guardrail. - Colusa Bridge, Spanning Sacramento River, Colusa, Colusa County, CA

  2. 29. VIEW EAST FROM DECKING ON NORTHWEST CORNER OF PIVOT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. VIEW EAST FROM DECKING ON NORTHWEST CORNER OF PIVOT PIER, DRIVE SYSTEM FOR SWING-SPAN INCLUDES: (from left to right) BULL WHEEL, GEARING AND DRIVE SHAFTS, INCLUDING MANUAL DRIVE ACCESSED THROUGH BRIDGE DECK, ELECTRIC LINES FROM SHORE, AND TRACK AND RAIL ON CONCRETE PIER - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

  3. Reconstruction of a pavement geothermal deicing system

    SciTech Connect

    Lund, J.W.

    1999-03-01

    In 1948, US 97 in Klamath Falls, Oregon was routed over Esplanade Street to Main Street and through the downtown area. In order to widen the bridge across the US Bureau of Reclamation A Canal and to have the road cross under the Southern Pacific Railroad main north-south line, a new bridge and roadway were constructed at the beginning of this urban route. Because the approach and stop where this roadway intersected Alameda Ave (now Hwy 50 -- Eastside Bypass) caused problems with traffic getting traction in the winter on an adverse 8% grade, a geothermal experiment in pavement de-icing was incorporated into the project. A grid system within the pavement was connected to a nearby geothermal well using a downhole heat exchanger (DHE). The 419-foot well provided heat to a 50-50 ethylene glycol-water solution that ran through the grid system at about 50 gpm. This energy could provide a relatively snow free pavement at an outside temperature of {minus}10 F and snowfall up to 3 inches per hour, at a heat requirement of 41 Btu/hr/ft{sup 2}. Over time, the well temperature dropped from 143 to 98 F at the surface. The bridge and surface pavement, geothermal well, and associated equipment were modified. This paper describes the modifications.

  4. STATUS OF POROUS PAVEMENT RESEARCH

    EPA Science Inventory

    This paper discusses the U.S. Environmental Protection Agency's porous pavement research program along with the economics, advantages, potential applications, and status and future research needs of porous pavements. Porous pavements are an available stormwater management techniq...

  5. Asphalt in Pavement Maintenance.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    Maintenance methods that can be used equally well in all regions of the country have been developed for the use of asphalt in pavement maintenance. Specific information covering methods, equipment and terminology that applies to the use of asphalt in the maintenance of all types of pavement structures, including shoulders, is provided. In many

  6. Detail of steel pier footing, deck plate girder, and connection ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of steel pier footing, deck plate girder, and connection to 150' Warren deck truss of Bridge No. 1396, Fourth Potomac and Second B&O Crossing, looking southwest. - Western Maryland Railway, Cumberland Extension, Pearre to North Branch, from WM milepost 125 to 160, Pearre, Washington County, MD

  7. Deci-Deck

    ERIC Educational Resources Information Center

    Fisher, John W.

    1975-01-01

    Mathematical concepts can be learned from games played with a standard deck of cards. New decks based on equivalent suits of fractions or decimals can also be created and adapted to any card games the students may wish to play. A deci-deck is an example. (Author/KM)

  8. 15. DETAIL OF EAST DECK GIRDER APPROACH SPANS AND STEEL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAIL OF EAST DECK GIRDER APPROACH SPANS AND STEEL CYLINDER PIERS, FROM EAST RIVERBANK. VIEW TO NORTHWEST. - MacArthur Bridge, Spanning Mississippi River on Highway 34 between IA & IL, Burlington, Des Moines County, IA

  9. 152. Linville River Recreation Area. View of the deck, sidewalks, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    152. Linville River Recreation Area. View of the deck, sidewalks, and stone guardrails of the Linville River Bridge looking southwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  10. 17. DETAIL VIEW SHOWING METAL DECK PLATES COVERING DAMAGED AREA ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. DETAIL VIEW SHOWING METAL DECK PLATES COVERING DAMAGED AREA OF WEST APPROACH SPAN - Middle Fork Stanislaus River Bridge, Spans Middle Fork Stanislaus River at State Highway 108, Dardanelle, Tuolumne County, CA

  11. 2. GENERAL VIEW, FROM DECK, SHOWING THREE OF FOUR TOWERS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. GENERAL VIEW, FROM DECK, SHOWING THREE OF FOUR TOWERS - Jones Beach State Parkway Channel Bascule Bridge MP-3, Route 908 E, spanning Sloop Channel Southeast of East Bay, Hempstead, Nassau County, NY

  12. 9. VIEW SHOWING TRUSSES FROM DECK WITH 4' RANGE POLE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. VIEW SHOWING TRUSSES FROM DECK WITH 4' RANGE POLE AT SECOND VERTICAL POST ON SOUTH SIDE, LOOKING WEST - White River Bridge, Spanning White River at U.S. Highway 70, De Valls Bluff, Prairie County, AR

  13. 29. DECK / WEB / LATERAL BRACING DETAIL OF CANTILEVER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. DECK / WEB / LATERAL BRACING DETAIL OF CANTILEVER ARM OF THROUGH TRUSS. VIEW TO WEST. - MacArthur Bridge, Spanning Mississippi River on Highway 34 between IA & IL, Burlington, Des Moines County, IA

  14. Interior view of eastern lift span, with decking above, looking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of eastern lift span, with decking above, looking back from center of span, toward lift mechanism area. - Arlington Memorial Bridge, Spanning Potomac River between Lincoln Memorial & Arlington National Cemetery, Washington, District of Columbia, DC

  15. 4. VIEW FROM EAST ABUTMENT SHOWING BASCULE LEAFS AND DECK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW FROM EAST ABUTMENT SHOWING BASCULE LEAFS AND DECK SUBSTRUCTURE. - Chicago River Bascule Bridge, Monroe Street, Spanning South Branch of Chicago River at Monroe Street, Chicago, Cook County, IL

  16. 6. DETAIL OF STEEL GUARDRAIL, CONCRETE CURB AND DECK EXPANSION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL OF STEEL GUARDRAIL, CONCRETE CURB AND DECK EXPANSION JOINT, WITH DRY BED OF RIO PUERCO IN BACKGROUND. VIEW TO EAST. - Rio Puerco Bridge, Mainline Road, spanning Rio Puerco, Holbrook, Navajo County, AZ

  17. 20. DETAIL VIEW OF DECK SOFFIT AND EXPANSION JOINT, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. DETAIL VIEW OF DECK SOFFIT AND EXPANSION JOINT, LOOKING SOUTHWEST FROM NORTH ABUTMENT - Chili Bar Bridge, Spanning South Fork of American River at State Highway 193, Placerville, El Dorado County, CA

  18. 4. LOOKING SOUTHWEST AT LATTICED GUARDRAIL, DIAGONALS, ASPHALT DECK AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. LOOKING SOUTHWEST AT LATTICED GUARDRAIL, DIAGONALS, ASPHALT DECK AND LACED ANGLES ON VERTICALS - Wayne County Bridge No. 122, Spanning West Fork Whitewater River at Main Street, Milton, Wayne County, IN

  19. Deck view, east approach; intersection of Carroll Road at left; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Deck view, east approach; intersection of Carroll Road at left; Interstate Highway 5 viaduct in background; view to southwest; 90mm lens - Carroll Overhead Bridge, Altamont Pass Road, Livermore, Alameda County, CA

  20. 6. VIEW, LOOKING EAST, SHOWING OPEN STEEL GRID DECK, TOP ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. VIEW, LOOKING EAST, SHOWING OPEN STEEL GRID DECK, TOP CHORD OF TRUSS, AND PIN CONNECTIONS - College Avenue Bridge, Pennsylvania Route 58/ Legislative Route 82 spanning Little Shenango River, Greenville, Mercer County, PA

  1. Deck view, west approach; former Western Pacific (now Union Pacific) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Deck view, west approach; former Western Pacific (now Union Pacific) Railroad at left; wind turbine generators atop hill in background; view to northeast; 90mm lens - Carroll Overhead Bridge, Altamont Pass Road, Livermore, Alameda County, CA

  2. 11. VIEW, LOOKING UNDER DECK TOWARD WEST END, SHOWING FLOOR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. VIEW, LOOKING UNDER DECK TOWARD WEST END, SHOWING FLOOR BEAMS, STRINGERS, CROSS BRACING AND CANTILEVERED WALKWAY - Milford Bridge, Spanning Little Miami River on U.S. 50, Milford, Clermont County, OH

  3. 12. REPRESENTATIVE VIEW OF UNDERSIDE OF DECK, LOOKING WEST FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. REPRESENTATIVE VIEW OF UNDERSIDE OF DECK, LOOKING WEST FROM UNDER BRIDGE AT ITS EASTERNMOST WIDE SPAN - Central of Georgia Railway, Bay Street Viaduct, U.S. 17 & Bay Street, spanning Central of Georgia Railroad, Savannah, Chatham County, GA

  4. 10. REPRESENTATIVE DETAIL VIEW OF CANTILEVERED DECK AND CONSTRUCTION OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. REPRESENTATIVE DETAIL VIEW OF CANTILEVERED DECK AND CONSTRUCTION OF BRIDGE SUBSTRUCTURE - Central of Georgia Railway, Bay Street Viaduct, U.S. 17 & Bay Street, spanning Central of Georgia Railroad, Savannah, Chatham County, GA

  5. 19. VERTICAL VIEW, FROM DECK, SHOWING CONNECTION OF CENTER TRUSS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. VERTICAL VIEW, FROM DECK, SHOWING CONNECTION OF CENTER TRUSS TENSION BARS, DIAGONAL TENSION RODS, AND LATTICE-JOINED VERTICAL CHANNELS - Lenox Bridge, Spanning Obion River, Rural Road S8025, Lenox, Dyer County, TN

  6. BELOW DECK DETAIL FROM EAST BANK. NOTE WROUGHT IRON LOWER ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BELOW DECK DETAIL FROM EAST BANK. NOTE WROUGHT IRON LOWER CHORD TENSION MEMBERS - Honey Run Bridge, Spanning Butte Creek, bypassed section of Honey Run Road (originally Carr Hill Road), Paradise, Butte County, CA

  7. 12. VIEW EAST ALONG DECK CENTERLINE, PRIOR TO CANTILEVERING SIDEWALK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. VIEW EAST ALONG DECK CENTERLINE, PRIOR TO CANTILEVERING SIDEWALK ON DOWNSTREAM SIDE File photo, Caltrans Office of Strutures Maintenance, March 1938. Photographer unknown. Photocopy of photograph - San Roque Canyon Bridge, State Highway 192, Santa Barbara, Santa Barbara County, CA

  8. 7. VIEW ACROSS DECK FACING SOUTHWEST; GREAT ARCH IN DISTANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW ACROSS DECK FACING SOUTHWEST; GREAT ARCH IN DISTANCE - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  9. 19. VIEW ACROSS DECK FACING SOUTHWEST, GREAT ARCH IN DISTANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. VIEW ACROSS DECK FACING SOUTHWEST, GREAT ARCH IN DISTANCE - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  10. 6. Oblique view of bottom chord, deck, and web members ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. Oblique view of bottom chord, deck, and web members of Warren truss span from abutment, facing northeast - Sault Ste. Marie International Railroad Bridge, Spanning Soo Locks at St. Marys Falls Canal, Sault Ste. Marie, Chippewa County, MI

  11. 11. DETAIL LOOKING THROUGH ARCH, SHOWING ROADWAY DECK, VERTICALS AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL LOOKING THROUGH ARCH, SHOWING ROADWAY DECK, VERTICALS AND LATERAL BRACES. VIEW TO SOUTHEAST. - Navajo Bridge, Spanning Colorado River at U.S. Highway 89 Alternate, Page, Coconino County, AZ

  12. 15. View to northeast. View along centerline from below deck; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. View to northeast. View along centerline from below deck; detail of bent and floor beams. (65mm lens) - South Fork Trinity River Bridge, State Highway 299 spanning South Fork Trinity River, Salyer, Trinity County, CA

  13. 20. WEB / DECK / LATERAL BRACING DETAIL OF THROUGH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. WEB / DECK / LATERAL BRACING DETAIL OF THROUGH TRUSSES. VIEW TO WEST. - Abraham Lincoln Memorial Bridge, Spanning Missouri River on Highway 30 between Nebraska & Iowa, Blair, Washington County, NE

  14. 22. INCLINED END POST / DECK / GUARDRAIL DETAIL OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. INCLINED END POST / DECK / GUARDRAIL DETAIL OF THROUGH TRUSSES. VIEW TO SOUTHEAST. - Abraham Lincoln Memorial Bridge, Spanning Missouri River on Highway 30 between Nebraska & Iowa, Blair, Washington County, NE

  15. 63. View aft along starboard side of hurricane deck from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    63. View aft along starboard side of hurricane deck from starboard bridge, short stack beyond lifeboat at left of image is donkey boiler stack. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  16. 20. DETAIL VIEW OF MOVABLE SPAN MACHINERY UNDER GRID DECK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    20. DETAIL VIEW OF MOVABLE SPAN MACHINERY UNDER GRID DECK AT CENTRAL CONCRETE SUPPORT PEDESTAL, SHOWING DRIVE GEARS, ELECTRIC MOTOR AND STEEL BEAMS (taken in January 1984) - Sharptown Bridge, Spanning Nanticoke River, State Route 313, Sharptown, Wicomico County, MD

  17. Longitudinal Section AA; Reflected Deck Plan; Reflected Ceiling Plan ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Longitudinal Section A-A; Reflected Deck Plan; Reflected Ceiling Plan - Shoreham Railroad Bridge, Former Addison County Railroad (later, Rutland Railroad, Addison Branch), spanning Lemon Fair River above Richville Pond, west of East Shoreham Road, Shoreham, Addison County, VT

  18. 7. WEST PORTAL AND DECK VIEW, FROM WEST, SHOWING PORTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. WEST PORTAL AND DECK VIEW, FROM WEST, SHOWING PORTAL CONFIGURATION AND LATERAL BRACING, STEEL MESH FLOOR, AND METAL RAILINGS - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  19. 8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. EAST PORTAL AND DECK VIEW, FROM EAST, SHOWING PORTAL CONFIGURATION AND LATERAL BRACING, STEEL MESH FLOOR, METAL RAILINGS, AND PORTION OF EAST APPROACH - Glendale Road Bridge, Spanning Deep Creek Lake on Glendale Road, McHenry, Garrett County, MD

  20. Weather network computer to control deck-heating system

    SciTech Connect

    Roe, A.

    1997-04-07

    A ground-source heating system for bridge deicing is briefly described in this article. The deck heating system will be controlled by the Oklahoma state weather network. Warm ground air will be pumped from more than 100 boreholes at least 200 feet deep. The heat transfer fluid, possibly propylene glycol, will be circulated through a sealed tube system in the bridge deck. Costs are estimated at $200,000 for the heating system and $840,000 for the total redecking project.

  1. 28. VIEW EAST FROM DECKING ON SOUTHWEST CORNER OF PIVOT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. VIEW EAST FROM DECKING ON SOUTHWEST CORNER OF PIVOT PIER, DRIVE SYSTEM FOR SWING-SPAN INCLUDES: (from left to right) ELECTRIC LINE FROM SHORE (bottom left), TRACK AND RAIL ON CONCRETE PIER, ELECTRIC MOTOR, GASOLINE MOTOR, SHAFTS TO WEDGE DRIVE CRANKS, WEDGE DRIVE DRIVE SHAFT, WEDGE DRIVE GEAR BOX, AND (on right) GEARING FOR MANUAL WEDGE DRIVE ACCESSED THROUGH BRIDGE DECK - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

  2. Pervious Pavement System Evaluation

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, grade...

  3. Evaluation of pavement texture

    NASA Astrophysics Data System (ADS)

    Henry, J. J.; Wambold, J. C.; Huihua, X.

    1984-10-01

    A system for pavement macrotexture measurement was evaluated. The system utilizes the principle of depolarization of reflected polarized light. The output of the system, the depolarized light number (DPN), is compared with other measures of pavement texture: sand-patch mean texture depth (MTD), British pendulum number (BPN), and outflow meter time (OFT) for 22 asphalt concrete sites and 5 portland cement concrete sites. The prediction of texture data from simultaneous measurements of ribbed and blank-tire skid resistance data was investigated. Using the two-tire data, it is possible to predict sand-patch mean texture depth (MTD) and Bristish pendulum number (BPN). Comparison of the two-tire data at accident sites demonstrates the potential to screen for wet weather accident sites by means of pavement surveys with the two tires.

  4. Experimental pavement delineation treatments

    NASA Astrophysics Data System (ADS)

    Bryden, J. E.; Lorini, R. A.

    1981-06-01

    Visibility and durability of materials used to delineate shoulders and medians adjacent to asphalt pavements were evaluated. Materials evaluated were polysulfide and coal tar epoxies, one and two component polyesters, portland cement, acrylic paints, modified-alkyd traffic paint, preformed plastic tape, and thermoplastic markings. Neat applications, sand mortars, and surface treatments were installed in several geometric patterns including cross hatches, solid median treatments, and various widths of edge lines. Thermoplastic pavement markings generally performed very well, providing good visibility under adverse viewing conditions for at least 4 years. Thermoplastic 4 in. wide edge lines appear to provide adequate visibility for most conditions.

  5. 11. Short subways led to the lower deck of the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Short subways led to the lower deck of the Detroit-Superior Bridge. Street cars entered the subways through open wells located in the center of the roadways. This undated photograph shows the Superior Avenue entrance. The view is looking west. Photograph courtesy Office of the Cuyahoga County Engineer in Cleveland, Ohio. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

  6. Pervious Pavement System Evaluation

    EPA Science Inventory

    Pervious pavement is a low impact development stormwater control. The Urban Watershed Management Branch of the U.S. Environmental Protection Agency in Edison, NJ, is evaluating concrete pavers as a popular implementation. The pollutant removal of a bench-scale permeable interlo...

  7. Small-format fly-over photography for highway bridge monitoring

    NASA Astrophysics Data System (ADS)

    Chen, Shen-En; Rice, Corey; Boyle, Chuck; Hauser, Edd; Philbrick, Brian

    2010-04-01

    Current bridge visual inspections are time-consuming, subjective, and rely heavily on personal experiences. The resulting ratings may be inconsistent. This paper discusses using remote-sensing technologies for bridge assessment, specifically, the use of high-resolution aerial imagery. The Small-Format Aerial Photography (SFAP) is a low-cost solution for bridge surface imaging. Providing top-down views, the airplanes flying at 1000 ft, can allow visualization of sub-inch (< 0.5 inch) cracks and joint openings on bridge decks or highway pavements. However, the site lighting may influence the quality of the images; surrounding tree shades and the highway wear surface reflectivity. Several examples of bridge evaluation using SFAP aerial photography are presented to demonstrate the capability of remote sensing as an effective tool for bridge construction monitoring and condition assessment. Several imaging issues are raised about analytical techniques that are necessary to ensure proper quantification of bridge problems, which include crack detection, movement determination, heavy trucking assessment, debris detection, channel width determination and environment assessment.

  8. Future Flight Decks

    NASA Technical Reports Server (NTRS)

    Arbuckle, P. Douglas; Abbott, Kathy H.; Abbott, Terence S.; Schutte, Paul C.

    1998-01-01

    The evolution of commercial transport flight deck configurations over the past 20-30 years and expected future developments are described. Key factors in the aviation environment are identified that the authors expect will significantly affect flight deck designers. One of these is the requirement for commercial aviation accident rate reduction, which is probably required if global commercial aviation is to grow as projected. Other factors include the growing incrementalism in flight deck implementation, definition of future airspace operations, and expectations of a future pilot corps that will have grown up with computers. Future flight deck developments are extrapolated from observable factors in the aviation environment, recent research results in the area of pilot-centered flight deck systems, and by considering expected advances in technology that are being driven by other than aviation requirements. The authors hypothesize that revolutionary flight deck configuration changes will be possible with development of human-centered flight deck design methodologies that take full advantage of commercial and/or entertainment-driven technologies.

  9. Fatigue performance of welded aluminum deck structures

    SciTech Connect

    Haagensen, P.J.; Ranes, M.; Kluken, A.O.; Kvale, I.

    1996-12-01

    Aluminum alloys are used increasingly in load carrying structures where low weight and low maintenance costs are at a premium. Helicopter decks, structures for living quarters and personnel transfer bridges between platforms are examples of offshore applications. While these structures are not usually subjected to high fatigue loads, the increasing use of aluminum in high speed ships, and more recently in highway bridge structures, makes the question of fatigue performance more important. In this paper the fatigue properties of small scale weldments in an AA6005 alloy are compared with the results of fatigue tests on full scale sections of welded extrusions in the same material, which were used in an aluminum bridge deck structure. The fatigue performance is also compared with the fatigue clauses in the new British design code BS8118 for aluminium structures and the proposed Eurocode 9. The prospects of using a new joining technique, friction stir welding (FSW), in the production of large scale panels for deck and ship hull structures is discussed. The FSW process is described briefly, and some fatigue test data are presented.

  10. POROUS PAVEMENT: RESEARCH; DEVELOPMENT; AND DEMONSTRATION

    EPA Science Inventory

    This paper discusses the U.S. Environmental Protection Agency's porous pavement research program along with the economics, advantages, potential applications, and status and future research needs of porous pavements. Porous pavements are an available stormwater management techniq...

  11. 15. Detail of west end of bridge, south elevation, showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Detail of west end of bridge, south elevation, showing underside of deck and floor beams; view to north. (Note 1892 Howard Street Bridge visible to north.) - Field Street Bridge, Spanning Old Colony railroad, Brockton, Plymouth County, MA

  12. 12. Standing at south end of bridge at centerline of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Standing at south end of bridge at centerline of roadway/deck showing decorative iron work at south end of bridge, looking north. - Colusa Bridge, Spanning Sacramento River, Colusa, Colusa County, CA

  13. 3. Credit JTL: Underside of south end of bridge showing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Credit JTL: Underside of south end of bridge showing deck construction and bridge abutment details - Reading-Halls Station Bridge, U.S. Route 220, spanning railroad near Halls Station, Muncy, Lycoming County, PA

  14. Geotextiles in Flexible Pavement Construction

    ERIC Educational Resources Information Center

    Alungbe, Gabriel D.

    2004-01-01

    People everywhere in the developed world regularly drive on paved roads. Learning about the construction techniques and materials used in paving benefits technology and construction students. This article discusses the use of geosynthetic textiles in pavement construction. It presents background on pavements and describes geotextiles and drainage…

  15. Geotextiles in Flexible Pavement Construction

    ERIC Educational Resources Information Center

    Alungbe, Gabriel D.

    2004-01-01

    People everywhere in the developed world regularly drive on paved roads. Learning about the construction techniques and materials used in paving benefits technology and construction students. This article discusses the use of geosynthetic textiles in pavement construction. It presents background on pavements and describes geotextiles and drainage

  16. Boeing flight deck design philosophy

    NASA Technical Reports Server (NTRS)

    Stoll, Harty

    1990-01-01

    Information relative to Boeing flight deck design philosophy is given in viewgraph form. Flight deck design rules, design considerations, functions allocated to the crew, redundancy and automation concerns, and examples of accident data that were reviewed are listed.

  17. Pavement recycling. Executive summary and report

    SciTech Connect

    1995-10-01

    The Federal Highway Administration (FHWA) initiated Demonstration Project 39 (DP 39) Recycling Asphalt Pavements in June 1976. The project showed that asphalt pavement recycling was a technically viable rehabitation technique, and it was estimated that the use of reclaimed asphalt pavement (RAP) would amount to approximately 15 percent of the total hot-mix asphalt (HMA) production by the mid-1980s. It was expected that most of the asphalt pavement removed would be reused in new pavement construction or overlays.

  18. 4. View in foreground of the deck of the Viaduct. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. View in foreground of the deck of the Viaduct. The ornamental wrought iron railing, sandstone sidewalks, and cobblestone roadway are visible. The bridge accommodated two streetcar lines flanked by two lanes of vehicular traffic. In the background is the Detroit- Superior High Level Bridge, which replaced the viaduct. View is looking Southwest. - Superior Avenue Viaduct, Cleveland East & West side, Cuyahoga Valley Vicinity, Cleveland, Cuyahoga County, OH

  19. 7. View showing placement of timber deck placement on chord ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View showing placement of timber deck placement on chord and built up construction of top chord and continuous construction through top panel points, eye bar construction on bottom chord - Bridge No. 2.4, Spanning Boiling Fork Creek at Railroad Milepost JC-2.4, Decherd, Franklin County, TN

  20. SOUTH ABUTMENT AND BELOW DECK DETAIL. NOTE THE FLOOR BEAMS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SOUTH ABUTMENT AND BELOW DECK DETAIL. NOTE THE FLOOR BEAMS ON THE APPROACH DO NOT REST ON THE LOWER CHORD BUT ARE SUSPENDED BELOW THE LOWER CHORDS BY MEANS LOOPED IRON HANGERS THAT WRAP AROUND WOODEN BLOCKS RESTING ON THE LOWER CHORD. - Crum Bridge, Spanning Little Muskingum River, TR 384A (formerly Old Camp Road), Rinard Mills, Monroe County, OH

  1. Corrosion in prestressed concrete: Pipes, piles, and decks

    SciTech Connect

    Szeliga, M.

    1995-12-31

    This is the first compilation or book focusing on prestressed concrete. It features 21 classic NACE papers on prestressed concrete piping, piles, bridge decks, and cathodic protection. It includes basic corrosion mechanisms of prestressed concrete structures with detailed case histories of corrosion failures and corrective measures.

  2. 31. DECK / VERTICAL / UPPER CHORD DETAIL OF THROUGH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. DECK / VERTICAL / UPPER CHORD DETAIL OF THROUGH TRUSS AT PIN-CONNECTED EXPANSION JOINT BETWEEN CANTILEVER ARM AND SUSPENDED SPAN. VIEW TO NORTHEAST. - MacArthur Bridge, Spanning Mississippi River on Highway 34 between IA & IL, Burlington, Des Moines County, IA

  3. CLOSEUP OF TYPICAL BUILTUP, RIVETED AND PIN CONNECTED DECK TRUSS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    CLOSE-UP OF TYPICAL BUILT-UP, RIVETED AND PIN CONNECTED DECK TRUSS LOOKING UP AND NORTHEAST. - Huey P. Long Bridge, Spanning Mississippi River approximately midway between nine & twelve mile points upstream from & west of New Orleans, Jefferson, Jefferson Parish, LA

  4. 18. DETAIL VIEW OF MOVABLE SPAN UNDER GRID DECK, ONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. DETAIL VIEW OF MOVABLE SPAN UNDER GRID DECK, ONE OF TWO DRIVE GEARS ON NORTH SIDE OF PEDESTAL THAT MESHES INTO FIXED GEAR RING, SET INTO TOP OF CENTER CONCRETE PEDESTAL, LOOKING SOUTHEAST (taken in March 1984) - Sharptown Bridge, Spanning Nanticoke River, State Route 313, Sharptown, Wicomico County, MD

  5. 22. View is from the deck, looking down to the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. View is from the deck, looking down to the junction of the last pony truss and the first through truss. This shows how the respective end posts are embedded into the concrete pier extension. There are only two of these, located on each end of pier #6. - Weidemeyer Bridge, Spanning Thomes Creek at Rawson Road, Corning, Tehama County, CA

  6. Pervious Pavement System Evaluation- Abstract

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  7. Soil on Phoenix Deck

    NASA Technical Reports Server (NTRS)

    2008-01-01

    This image, taken by the Surface Stereo Imager (SSI) of NASA's Phoenix Lander, shows Martian soil piled on top of the spacecraft's deck and some of its instruments. Visible in the upper-left portion of the image are several wet chemistry cells of the lander's Microscopy, Electrochemistry, and Conductivity Analyzer (MECA). The instrument on the lower right of the image is the Thermal and Evolved-Gas Analyzer. The excess sample delivered to the MECA's sample stage can be seen on the deck in the lower left portion of the image.

    This image was taken on Martian day, or sol, 142, on Saturday, Oct. 19, 2008. Phoenix landed on Mars' northern plains on May 25, 2008.

    The Phoenix Mission is led by the University of Arizona, Tucson, on behalf of NASA. Project management of the mission is by NASA's Jet Propulsion Laboratory, Pasadena, Calif. Spacecraft development is by Lockheed Martin Space Systems, Denver.

  8. Designing Flight Deck Procedures

    NASA Technical Reports Server (NTRS)

    Degani, Asaf; Wiener, Earl

    2005-01-01

    Three reports address the design of flight-deck procedures and various aspects of human interaction with cockpit systems that have direct impact on flight safety. One report, On the Typography of Flight- Deck Documentation, discusses basic research about typography and the kind of information needed by designers of flight deck documentation. Flight crews reading poorly designed documentation may easily overlook a crucial item on the checklist. The report surveys and summarizes the available literature regarding the design and typographical aspects of printed material. It focuses on typographical factors such as proper typefaces, character height, use of lower- and upper-case characters, line length, and spacing. Graphical aspects such as layout, color coding, fonts, and character contrast are discussed; and several cockpit conditions such as lighting levels and glare are addressed, as well as usage factors such as angular alignment, paper quality, and colors. Most of the insights and recommendations discussed in this report are transferable to paperless cockpit systems of the future and computer-based procedure displays (e.g., "electronic flight bag") in aerospace systems and similar systems that are used in other industries such as medical, nuclear systems, maritime operations, and military systems.

  9. Interior of the Fisher School Covered Bridge, view to north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior of the Fisher School Covered Bridge, view to north showing road deck, guardrail, and howe truss. - Fisher School Covered Bridge, Crab Creek Road at Fiver Rivers Road, Fisher, Lincoln County, OR

  10. 24. Detail view north under bridge showing arched bascule girder, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Detail view north under bridge showing arched bascule girder, deck girders and cross beams, and bracing of east bascule leaf. - Yellow Mill Bridge, Spanning Yellow Mill Channel at Stratford Avenue, Bridgeport, Fairfield County, CT

  11. 10. Substructure of bridge, showing timber bents, piles, crossbracing, caps ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Substructure of bridge, showing timber bents, piles, cross-bracing, caps and stringers under deck. View to northeast. - Outlet Creek Bridge, Sullivan Lake Ranger Administrative Site, Metaline Falls, Pend Oreille County, WA

  12. 14. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING GIRDERS, BEARING SHOES, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING GIRDERS, BEARING SHOES, FLOOR BEAMS, STRINGERS, LATERAL BRACING AND CONCRETE DECK. VIEW TO NORTH. - Rio Puerco Bridge, Mainline Road, spanning Rio Puerco, Holbrook, Navajo County, AZ

  13. 6. DETAIL VIEW OF SINGLE PANEL POINTS TAKEN FROM BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. DETAIL VIEW OF SINGLE PANEL POINTS TAKEN FROM BRIDGE DECK, SHOWING CONNECTION BETWEEN VERTICAL AND UPPER CHORD MEMBER. - White Bowstring Arch Truss Bridge, Spanning Yellow Creek at Cemetery Drive (Riverside Drive), Poland, Mahoning County, OH

  14. 4. SIDE VIEW OF BRIDGE, LOOKING SOUTHWEST, SHOWING ARCHES, CANTILEVERED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. SIDE VIEW OF BRIDGE, LOOKING SOUTHWEST, SHOWING ARCHES, CANTILEVERED WALKWAY, DECK BEAMS AND STREAMBED - Benson Street Concrete Bowstring Bridge, Spanning Mill Creek at Benson Street, Lockland, Hamilton County, OH

  15. View of Tensaw River Bridge, looking northeast. Photograph taken from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Tensaw River Bridge, looking northeast. Photograph taken from observation deck of Battleship USS Alabama - Tensaw River Lift Bridge, Spanning Tensaw River at U.S. Highway 90, Mobile, Mobile County, AL

  16. Pervious Pavement System Evaluation-Poster

    EPA Science Inventory

    Pervious pavement is a low impact development stormwater control. The Environmental Protection Agency's Urban Watershed Management Branch is evaluating interlocking concrete pavingstone pervious pavement systems. The pavingstones themselves are impermeable, but the spaces between...

  17. Quantifying Evaporation in a Permeable Pavement System

    EPA Science Inventory

    Studies quantifying evaporation from permeable pavement systems are limited to a few laboratory studies and one field application. This research quantifies evaporation for a larger-scale field application by measuring the water balance from lined permeable pavement sections. Th...

  18. 12. GENERAL VIEW OF THE WESTERN PORTION OF THE BRIDGE. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. GENERAL VIEW OF THE WESTERN PORTION OF THE BRIDGE. IT CONSISTS (LEFT TO RIGHT) OF SIX PRATT DECK TRUSSES, A PENNSYLVANIA THROUGH TRUSS, AND TWO MORE PRATT DECK TRUSSES. THE AERIAL VIEW IS FROM THE SOUTHWEST - Susquehanna River Bridge, Spanning Susquehanna River, Havre de Grace, Harford County, MD

  19. 10. DECK VIEW FORWARD FROM MAIN DECK TO FORECASTLE. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DECK VIEW FORWARD FROM MAIN DECK TO FORECASTLE. NOTE PIPE FITTING FOR OIL PUMPING SYSTEM (DISCHARGE). THE HATCH OPENINGS TO RIGHT ARE ABOVE THE SHIP'S BOILER ROOM. - Ship "Falls of Clyde", Hawaii Maritime Center,Pier 7, Honolulu, Honolulu County, HI

  20. Impact of pavement conditions on crash severity.

    PubMed

    Li, Yingfeng; Liu, Chunxiao; Ding, Liang

    2013-10-01

    Pavement condition has been known as a key factor related to ride quality, but it is less clear how exactly pavement conditions are related to traffic crashes. The researchers used Geographic Information System (GIS) to link Texas Department of Transportation (TxDOT) Crash Record Information System (CRIS) data and Pavement Management Information System (PMIS) data, which provided an opportunity to examine the impact of pavement conditions on traffic crashes in depth. The study analyzed the correlation between several key pavement condition ratings or scores and crash severity based on a large number of crashes in Texas between 2008 and 2009. The results in general suggested that poor pavement condition scores and ratings were associated with proportionally more severe crashes, but very poor pavement conditions were actually associated with less severe crashes. Very good pavement conditions might induce speeding behaviors and therefore could have caused more severe crashes, especially on non-freeway arterials and during favorable driving conditions. In addition, the results showed that the effects of pavement conditions on crash severity were more evident for passenger vehicles than for commercial vehicles. These results provide insights on how pavement conditions may have contributed to crashes, which may be valuable for safety improvement during pavement design and maintenance. Readers should notice that, although the study found statistically significant effects of pavement variables on crash severity, the effects were rather minor in reality as suggested by frequency analyses. PMID:23892046

  1. Pavement roughness measurement based on structure light

    NASA Astrophysics Data System (ADS)

    Liu, WanYu; Sun, Xiaoming; Huang, Jian Ping; Xie, Kai

    2008-10-01

    Pavement roughness is an important index to reflect the quality of pavement. To improve the efficiency of pavement roughness measurement, a novel pavement roughness measurement system based on structured light vision inspection is proposed in this paper. By describing the principle of structured light inspection and measurement system design, it is stressed that the proposed system can be used to acquire a continuous longitudinal profile of pavement and International Roughness Index by using the structured light illumination and CCD. Some experiments are performed to test orientation precision and performance of the system. The experimental results show that the system has some pros such as high orientation precision, good stability and low cost.

  2. The Concrete and Pavement Challenge

    ERIC Educational Resources Information Center

    Roman, Harry T.

    2012-01-01

    The modern world is characterized by the extensive use of concrete and asphalt pavement. Periodically, these materials are replaced and the old materials disposed of. In this challenge, students will be asked to develop ways to reuse the old materials. It is important for students to understand how concrete and asphalt are made and applied, as

  3. 27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. VIEW NORTHWEST FROM DECKING ON SOUTHEAST CORNER OF PIVOT PIER, DRIVE SYSTEM FOR SWING-SPAN INCLUDES: (from left to right) WEDGE DRIVE GEAR BOX, SHAFTS TO WEDGE DRIVE DRIVE, WEDGE DRIVE CRANK SHAFTS, ELECTRIC MOTOR, INTERNATIONAL HARVESTER GASOLINE ENGINE, CONTROL RODS FOR STARTING AND CHOKING ENGINE, PIVOT (bottom center), AND TRACK ON CONCRETE PIER - Tipers Bridge, Spanning Great Wicomico River at State Route 200, Kilmarnock, Lancaster County, VA

  4. 13. Looking north, from the southern approach to the bridge. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Looking north, from the southern approach to the bridge. The bridge deck, which is concrete with several patch coats of asphalt (now chiefly gravel and some turf), demonstrates a sharp gradient from the abutment to the bridge center line. - Vigo County Bridge No. 139, Spanning Sugar Creek at Seventy-fourth Place, Terre Haute, Vigo County, IN

  5. View to southwest along bridge alignment, showing reverse curve from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View to southwest along bridge alignment, showing reverse curve from near deck level; Southern Pacific Railroad track passing beneath bridge; Western Pacific Railroad track out of sight behind bridge; photographer unknown; 1933 photo from collection of Office of Structures Maintenance, California Department of Transportation, Sacramento - Carroll Overhead Bridge, Altamont Pass Road, Livermore, Alameda County, CA

  6. 14. DETAIL VIEW OF BRIDGE, LOOKING NORTH, SHOWING DAMAGE TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. DETAIL VIEW OF BRIDGE, LOOKING NORTH, SHOWING DAMAGE TO FLOOR BEAMS AND DECK OF WEST APPROACH SPAN, CAUSED WHEN CONTRACTOR'S FORCES, WORKING ON ADJACENT ABUTMENT FOR REPLACEMENT BRIDGE, DYNAMITED GRANITE BOULDERS INTO UPSTREAM SIDE OF HISTORIC BRIDGE - Middle Fork Stanislaus River Bridge, Spans Middle Fork Stanislaus River at State Highway 108, Dardanelle, Tuolumne County, CA

  7. Generation mechanisms of tire-pavement noise

    NASA Astrophysics Data System (ADS)

    Dare, Tyler P.

    Tire-pavement noise is the dominant source of traffic noise at highway speeds. It is the result of a combination of several noise generation mechanisms, including tire carcass vibration and tread block vibration. Because multiple mechanisms are involved, it is difficult to predict the effects of changes in pavement parameters on tire-pavement noise. In this research, a set of experimental techniques were developed to decompose a measured tire-pavement noise spectrum into a set of constituent spectra relating to each generation mechanism. Three principal mechanisms were identified: treadband vibration, sidewall vibration, and tangential tread block vibration. By combining the constituent spectra associated with these mechanisms, it was possible to accurately predict the total tire-pavement noise spectrum. The constituent spectra were fit to tire-pavement noise data measured on asphalt and concrete pavements at highway speeds. It was found that the constituent spectra fit the measured data well, and a two-parameter model was developed to predict tire-pavement noise levels from pavement texture data.

  8. A design system for rigid pavement rehabilitation

    NASA Astrophysics Data System (ADS)

    Seeds, S. B.; McCullough, B. F.; Hudson, W. R.

    1982-01-01

    The development, use, and applicability of a rigid pavement rehabilitation design system, RPRDS, developed for use by the Texas State Department of Highways and Public Transportation is described. Like other pavement design systems, RPRDS makes use of the systems approach to incorporate a number of pavement design and analytical models into a computer program, RPRDS-1, for the generation, analysis, and comparison of numerous pavement design strategies. Basically, RPRDS generates a number of feasible overlay design strategies based on user inputs, performs a present value cost analysis on each, and then presents those which are optimal.

  9. Improving the distribution and reducing the magnitude of pavement damage

    NASA Astrophysics Data System (ADS)

    Barker, W. R.; Chou, U. T.

    1980-08-01

    In the analysis of flexible pavement, the layered elastic theory was used to compute the pavement response. For the rigid pavement, finite difference, layered elastic theory, and Westergard procedures were used to compute tensile stresses in concrete that formed the basis for predicting allowable stress repetitions. For flexible pavement, the only effective means to reduce pavement damage was to modify the wheel assembly to reduce stress or strain at the critical locations in the pavement systems. The most effective modification would be to increase the spacing between duals. For rigid pavements, the edge effect was critical, thus suggesting that modifications to shift the loading away from the pavement edge would be effective.

  10. On the typography of flight-deck documentation

    NASA Technical Reports Server (NTRS)

    Degani, Asaf

    1992-01-01

    Many types of paper documentation are employed on the flight-deck. They range from a simple checklist card to a bulky Aircraft Flight Manual (AFM). Some of these documentations have typographical and graphical deficiencies; yet, many cockpit tasks such as conducting checklists, way-point entry, limitations and performance calculations, and many more, require the use of these documents. Moreover, during emergency and abnormal situations, the flight crews' effectiveness in combating the situation is highly dependent on such documentation; accessing and reading procedures has a significant impact on flight safety. Although flight-deck documentation are an important (and sometimes critical) form of display in the modern cockpit, there is a dearth of information on how to effectively design these displays. The object of this report is to provide a summary of the available literature regarding the design and typographical aspects of printed matter. The report attempts 'to bridge' the gap between basic research about typography, and the kind of information needed by designers of flight-deck documentation. The report focuses on typographical factors such as type-faces, character height, use of lower- and upper-case characters, line length, and spacing. Some graphical aspects such as layout, color coding, fonts, and character contrast are also discussed. In addition, several aspects of cockpit reading conditions such as glare, angular alignment, and paper quality are addressed. Finally, a list of recommendations for the graphical design of flight-deck documentation is provided.

  11. A three dimensional approach for tracking cracks in bridges using GPR

    NASA Astrophysics Data System (ADS)

    Benedetto, Andrea

    2013-10-01

    Corrosion associated with reinforcing bars is the most significant contributor to bridge deficiencies. The corrosion is usually caused by moisture and chloride ion exposure. The reinforcing bars are attacked by corrosion and yield expansive corrosion products. These oxidation products occupy a larger volume than the original intact steel and internal expansive stresses lead to cracking and debonding. There are some conventional inspection methods for the detection of the reinforcing bar's corrosion but they can be invasive and destructive, often laborious, and lane closure is required and it is difficult or unreliable for any quantification of corrosion. For these reasons, bridge engineers always prefer more to use the ground penetrating radar (GPR) technique. In this work a novel numerical approach for three dimensional tracking and mapping of cracks in the bridge is proposed. The work starts from some interesting results based on the use of the 3D imaging technique in order to improve the potentiality of the GPR to detect voids, cracks or buried objects. The numerical approach has been tested on data acquired on a bridge by using a pulse GPR system specifically designed for bridge deck and pavement inspection. The equipment integrates two arrays of Ultra Wide Band ground coupled antennas, having a main working frequency of 2 GHz. The two arrays are using antennas arranged with a different polarization. The cracks, associated often to moisture increase and higher values of the dielectric constant, produce a not negligible increase of the signal amplitude. Following this, the algorithm, organized in preprocessing, processing and postprocessing stages, analyzes the signal by comparing the value of the amplitude all over the domain of the radar scan.

  12. 17. LOOKING FROM DECK ABOVE MESS UP AT DECK ABOVE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. LOOKING FROM DECK ABOVE MESS UP AT DECK ABOVE CO'S STATEROOM. RECTANGULAR WINDOWS IS AT REAR OF PILOT HOUSE. TO RIGHT OF WINDOW IS TOP OF STAIRS TO STARBOARD WING OF FLYBRIDGE. AT EXTREME RIGHT IS ENGINE CONTROLS AND IN BACKGROUND IS COMPASS WITH COVER OVER IT. RIGHT EDGE OF THIS IMAGE IS SAME AS IMAGE 14, JUST OBSTRUCTED IN IMAGE 14 BY LIFE PRESERVER AND SEAT. - U.S. Coast Guard Cutter WHITE LUPINE, U.S. Coast Guard Station Rockland, east end of Tillson Avenue, Rockland, Knox County, ME

  13. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  14. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  15. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  16. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  17. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  18. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  19. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  20. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  1. 46 CFR 178.410 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.410 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck...

  2. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  3. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  4. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1110 Drainage of flush deck vessels. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel must...

  5. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  6. 46 CFR 178.430 - Drainage of well deck vessels.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... TONS) INTACT STABILITY AND SEAWORTHINESS Drainage of Weather Decks § 178.430 Drainage of well deck vessels. (a) The weather deck on a well deck vessel must be watertight. (b) The area required on a...

  7. Pervious Pavement System Evaluation-Paper

    EPA Science Inventory

    The use of a pervious pavement can be effective as a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete paver systems as a type of porous pavement. Although the pavers are impermeable, the spaces between the pave...

  8. 46 CFR 45.31 - Deck line.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Deck line. 45.31 Section 45.31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Load Line Marks 45.31 Deck line. (a) Each vessel must be marked with a deck line on the outer surface of the shell on each side...

  9. 33 CFR 155.790 - Deck lighting.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Deck lighting. 155.790 Section..., Procedures, Equipment, and Records § 155.790 Deck lighting. (a) A self-propelled vessel with a capacity of... and sunrise must have deck lighting that adequately illuminates— (1) Each transfer operations...

  10. 33 CFR 155.790 - Deck lighting.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Deck lighting. 155.790 Section..., Procedures, Equipment, and Records § 155.790 Deck lighting. (a) A self-propelled vessel with a capacity of... and sunrise must have deck lighting that adequately illuminates— (1) Each transfer operations...

  11. 33 CFR 155.790 - Deck lighting.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Deck lighting. 155.790 Section..., Procedures, Equipment, and Records § 155.790 Deck lighting. (a) A self-propelled vessel with a capacity of... and sunrise must have deck lighting that adequately illuminates— (1) Each transfer operations...

  12. 33 CFR 155.790 - Deck lighting.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Deck lighting. 155.790 Section..., Procedures, Equipment, and Records § 155.790 Deck lighting. (a) A self-propelled vessel with a capacity of... and sunrise must have deck lighting that adequately illuminates— (1) Each transfer operations...

  13. 33 CFR 155.790 - Deck lighting.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Deck lighting. 155.790 Section..., Procedures, Equipment, and Records § 155.790 Deck lighting. (a) A self-propelled vessel with a capacity of... and sunrise must have deck lighting that adequately illuminates— (1) Each transfer operations...

  14. 46 CFR 108.486 - Helicopter decks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the...

  15. 46 CFR 108.486 - Helicopter decks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the...

  16. 46 CFR 108.486 - Helicopter decks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the...

  17. 46 CFR 108.486 - Helicopter decks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the...

  18. 46 CFR 108.486 - Helicopter decks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Helicopter decks. 108.486 Section 108.486 Shipping COAST... Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.486 Helicopter decks. At least two of the accesses to the helicopter landing deck must each have a fire hydrant on the...

  19. 46 CFR 45.31 - Deck line.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Deck line. 45.31 Section 45.31 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES GREAT LAKES LOAD LINES Load Line Marks 45.31 Deck line. (a) Each vessel must be marked with a deck line on the outer surface of the shell on each side...

  20. Improving rutting resistance of pavement structures using geosynthetics: an overview.

    PubMed

    Mirzapour Mounes, Sina; Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting). PMID:24526919

  1. Improving Rutting Resistance of Pavement Structures Using Geosynthetics: An Overview

    PubMed Central

    Karim, Mohamed Rehan; Khodaii, Ali; Almasi, Mohammad Hadi

    2014-01-01

    A pavement structure consists of several layers for the primary purpose of transmitting and distributing traffic loads to the subgrade. Rutting is one form of pavement distresses that may influence the performance of road pavements. Geosynthetics is one type of synthetic materials utilized for improving the performance of pavements against rutting. Various studies have been conducted on using different geosynthetic materials in pavement structures by different researchers. One of the practices is a reinforcing material in asphalt pavements. This paper intends to present and discuss the discoveries from some of the studies on utilizing geosynthetics in flexible pavements as reinforcement against permanent deformation (rutting). PMID:24526919

  2. 23. General views of Moody Bridge, in descending order: 1) ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. General views of Moody Bridge, in descending order: 1) the northern approach with a partial 'barrel shot', 2) partial view of southern approach detailing bridge decking, railing and portal bracing, and 3) an elevation view to the northeast showing timber piers and abutment of southern approach. - Moody Bridge, Spanning South Fork Eel River, Garberville, Humboldt County, CA

  3. 61. MISSISSIPPI, NOXUBEE CO. MACON MAHORNER'S BRIDGE Ms. 14, 6 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. MISSISSIPPI, NOXUBEE CO. MACON MAHORNER'S BRIDGE Ms. 14, 6 miles E to McLeod, 4.5 miles S on McLeod-Shuqualak road. Overall view of bridge, looking E along N side, from below deck level. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  4. 1. General view of bridge looking north. This is the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. General view of bridge looking north. This is the only suspension bridge in Cleveland. It was designed by Wilbur J. Watson and Associates, Consulting Engineers. Sections of the Wooden deck are missing, and the bridge is no longer used. - Sidaway Avenue Footbridge, Jackowo & Garden Valley neighborhood Vicinity, Cleveland, Cuyahoga County, OH

  5. PERSPECTIVE WITH WEST PORTAL. THE BRIDGE IS CLAD IN HORIZONTAL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE WITH WEST PORTAL. THE BRIDGE IS CLAD IN HORIZONTAL CLAPBOARD SIDING AND HAS A SHEET METAL ROOF. NOTE THE TWO OPENINGS THAT RUN THE LENGTH OF THE BRIDGE; ONE IS AT THE EAVES AND THE OTHER IS ABOUT 4? ABOVE THE DECK. - Dreibelbis Station Bridge, Spanning Maiden Creek, Balthaser Road (TR 745), Lenhartsville, Berks County, PA

  6. Assessment of highway pavements using GPR

    NASA Astrophysics Data System (ADS)

    Plati, Christina; Loizos, Andreas

    2015-04-01

    Highway infrastructure is a prerequisite for a functioning economy and social life. Highways, often prone to congestion and disruption, are one of the aspects of a modern transport network that require maximum efficiency if an integrated transport network, and sustainable mobility, is to be achieved. Assessing the condition of highway structures, to plan subsequent maintenance, is essential to allow the long-term functioning of a road network. Optimizing the methods used for such assessment will lead to better information being obtained about the road and underlying ground conditions. The condition of highway structures will be affected by a number of factors, including the properties of the highway pavement, the supporting sub-base and the subgrade (natural ground), and the ability to obtain good information about the entire road structure, from pavement to subgrade, allows appropriate maintenance programs to be planned. The maintenance of highway pavements causes considerable cost and in many cases obstruction to traffic flow. In this situation, methods that provide information on the present condition of pavement structure non-destructively and economically are of great interest. It has been shown that Ground-Penetrating-Radar (GPR), which is a Non Destructive Technique (NDT), can deliver information that is useful for the planning of pavement maintenance activities. More specifically GPR is used by pavement engineers in order to determine physical properties and characteristics of the pavement structure, information that is valuable for the assessment of pavement condition. This work gives an overview on the practical application of GPR using examples from highway asphalt pavements monitoring. The presented individual applications of GPR pavement diagnostics concern structure homogeneity, thickness of pavement layers, dielectric properties of asphalt materials etc. It is worthwhile mentioning that a number of applications are standard procedures, either separately or in combination with other NDT methods, but even for them there is still a room for improvement and there is still need to set stricter regulations Comparisons between radar results and ground truth data produce evidence in support of the statement that the accuracy and reliability of radar results is sufficient for facing many issues related to the evaluation of asphalt pavements. Thus, benefits and limits of this method are shown and recommendations for GPR inspections are presented. Acknowledgments: This work benefited from networking activities carried out within the EU funded COST Action TU1208 "Civil Engineering Applications of Ground Penetrating Radar."

  7. The Edison Environmental Center Permeable Pavement Site

    EPA Science Inventory

    This a presentation for a Community Outreach Event called "Chemistry Works and Celebration of International Year of Chemistry." It will review the permeable pavement research project at the Edison Environmental center.

  8. Permeable Pavement Research - Edison, New Jersey

    EPA Science Inventory

    This presentation provides the background and summary of results collected at the permeable pavement parking lot monitored at the EPA facility in Edison, NJ. This parking lot is surfaced with permeable interlocking concrete pavers (PICP), pervious concrete, and porous asphalt. ...

  9. Pervious Pavement System Evaluation- Abstract 1

    EPA Science Inventory

    Porous pavement is a low impact development stormwater control. The Urban Watershed Management Branch is evaluating interlocking concrete pavers as a popular implementation. The pavers themselves are impermeable, but the spaces between the pavers are backfilled with washed, gra...

  10. Advances in the design of pavement surfaces

    NASA Astrophysics Data System (ADS)

    Johnsen, William Aage

    The objective is to advance the design of pavement surfaces. The goal is to design a pavement with low wear and high friction for tires. The objective is accomplished by relating the pavement texture to its performance and finishing technique. Pavement texture is represented by characterization parameters calculated from topographic data sets. Data sets are acquired using a Scanning Laser Position Sensor (SLPS, Johnsen 1995) capable of measuring over a 150 x 150 x 50 mm (x, y, z) volume, at a resolution of 25 mum on each axis. Standard and scale-sensitive fractal analysis methods are used and a computer model is developed to calculate characterization parameters from the topographic data sets. The fractal parameters complexity (ASFC) and smooth-rough crossover (SRC) are able to differentiate certain pavement textures. The computer model, when constrained to various settings, correlates with the ASTM E965 sand-patch volumetric technique with a slope of 1.156 0.247 and a correlation coefficient (rsp2) of 0.961 0.016. Neural networks are used to relate pavement texture to in-situ performance. Nearly 75% of the neural network input arrays can predict the friction coefficient with a correlation coefficient of greater than 0.90. The parameters ASFC and SRC increase, and mean texture depth measurements made by a van or the beam method (MTDVB) decrease, this statistical significance. A new device is developed to measure 2500 coefficients of friction per second to investigate friction and wear of tires over a 60 millisecond impact on varying pavement specimens. The mean and standard deviation of the measured coefficient of friction curves differentiate the direction of the pavement brush finish. It is shown that low wear rates are possible with high coefficients of friction.

  11. LASE equipment mounting deck assembly

    NASA Technical Reports Server (NTRS)

    1991-01-01

    LASE installation graphic illustration; LASE equipment mounting deck assembly graphic illustration. The Lidar Atmospheric Sensing experimental (LASE) instrument, which lies on NASA's high-altitude ER-2 aircraft, has been developed AS A PRECURSOR TO FUTURE NASA Space-Based Global Lidar missions. LASE performed the first ever, fully autonomous, Differential Absorption Lidar (DIAL) vertical profile measurements of water vapor and Lidar measurements of aerosols and provided the highest altitude tropospheric data ever recorded.

  12. Fusing complementary images for pavement cracking measurements

    NASA Astrophysics Data System (ADS)

    Yao, Ming; Zhao, Zuyun; Yao, Xun; Xu, Bugao

    2015-02-01

    Cracking is a major pavement distress that jeopardizes road serviceability and traffic safety. Automated pavement distress survey (APDS) systems have been developed using digital imaging technology to replace human surveys for more timely and accurate inspections. Most APDS systems require special lighting devices to illuminate pavements and prevent shadows of roadside objects that distort cracks in the image. Most artificial lighting devices are laser based, and are either hazardous to unprotected people or require dedicated power supplies on the vehicle. This study was aimed to develop a new imaging system that can scan pavement surface at highway speed and determine the level of severity of pavement cracking without using any artificial lighting. The new system consists of dual line-scan cameras that are installed side by side to scan the same pavement area as the vehicle moves. Cameras are controlled with different exposure settings so that both sunlit and shadowed areas can be visible in two separate images. The paired images contain complementary details useful for reconstructing an image in which the shadows are eliminated. This paper intends to present (1) the design of the dual line-scan camera system, (2) a new calibration method for line-scan cameras to rectify and register paired images, (3) a customized image-fusion algorithm that merges the multi-exposure images into one shadow-free image for crack detection, and (4) the results of the field tests on a selected road over a long period.

  13. Reducing traffic noise with quieter pavements

    NASA Astrophysics Data System (ADS)

    Donavan, Paul

    2005-09-01

    In recent years, interest has increased in the use of pavement type to reduce traffic noise. This has been driven by public concern over noise from freeways and state transportation agencies' interest in using pavement instead of sound walls to mitigate traffic noise. Beginnings of the recent interest go back to 1998 with the formation of the Institute for Safe, Quiet & Durable Highways at Purdue University and the initiation long-term research by the California Department of Transportation (Caltrans) on the effectiveness of quieter pavements. In 2002, the State of Arizona announced plans to overlay 115 miles of concrete freeway in the greater Phoenix area with a quieter asphalt rubber surface. This turned into the first Quiet Pavement Pilot Program in partnership between Federal Highway Administration (FHWA) and the Arizona Department of Transportation. Since that time, the FHWA in cooperation with the American Association of State Highway Transportation Agencies conducted a fact finding ``Scan'' tour in Europe to evaluate their quiet pavement technology and policy. This was followed by the first comparative tire/pavement noise testing in the US and Europe using the same procedures and test tires. The results, issues, and future directions surrounding these activities will be discussed.

  14. Fracture of highway and airport pavements

    NASA Astrophysics Data System (ADS)

    Ramsamooj, D. V.

    1993-03-01

    Existing solutions for the stresses in a cracked slab containing a crack and supported by an elastic foundation are extended to obtain the stress intensity factor (SIF) for a crack in a pavement subjected to moving vehicular loads. In the existing solutions the stresses can be obtained only for a uniform bending stress (before the crack occurs) along the crack surface. For pavements subjected to moving vehicular loads, the stress distribution along the crack surface is not uniform and the approximation of a uniform stress is often unsatisfactory. The present work extends the above solutions to cover more realistic loading of highway and airport pavements. This facilitates the application of the principles of fracture mechanics to the fatigue crack propagation and fracture of pavements. Beginning with a part-through semi-elliptical starter crack, the crack is assumed to grow under load and the SIF is presented at various stages of crack growth, from the starter crack into a short through-crack that eventually becomes a very long through-crack. Some examples of the fracture of typical rigid and flexible highway and airport pavements are presented to show the need to consider fracture in the design of pavements.

  15. 23 CFR 661.47 - Can bridge maintenance be performed with IRRBP funds?

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 23 Highways 1 2012-04-01 2012-04-01 false Can bridge maintenance be performed with IRRBP funds... ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.47 Can bridge maintenance be performed with IRRBP funds? No. Bridge maintenance repairs, e.g., guard rail repair, deck repairs, repair...

  16. 23 CFR 661.47 - Can bridge maintenance be performed with IRRBP funds?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Can bridge maintenance be performed with IRRBP funds... ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.47 Can bridge maintenance be performed with IRRBP funds? No. Bridge maintenance repairs, e.g., guard rail repair, deck repairs, repair...

  17. 23 CFR 661.47 - Can bridge maintenance be performed with IRRBP funds?

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Can bridge maintenance be performed with IRRBP funds... ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.47 Can bridge maintenance be performed with IRRBP funds? No. Bridge maintenance repairs, e.g., guard rail repair, deck repairs, repair...

  18. 23 CFR 661.47 - Can bridge maintenance be performed with IRRBP funds?

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 23 Highways 1 2013-04-01 2013-04-01 false Can bridge maintenance be performed with IRRBP funds... ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.47 Can bridge maintenance be performed with IRRBP funds? No. Bridge maintenance repairs, e.g., guard rail repair, deck repairs, repair...

  19. 23 CFR 661.47 - Can bridge maintenance be performed with IRRBP funds?

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 23 Highways 1 2014-04-01 2014-04-01 false Can bridge maintenance be performed with IRRBP funds... ENGINEERING AND TRAFFIC OPERATIONS INDIAN RESERVATION ROAD BRIDGE PROGRAM § 661.47 Can bridge maintenance be performed with IRRBP funds? No. Bridge maintenance repairs, e.g., guard rail repair, deck repairs, repair...

  20. Thermal Stability Analysis under Embankment with Asphalt Pavement and Cement Pavement in Permafrost Regions

    PubMed Central

    Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results. PMID:24027444

  1. Thermal stability analysis under embankment with asphalt pavement and cement pavement in permafrost regions.

    PubMed

    Junwei, Zhang; Jinping, Li; Xiaojuan, Quan

    2013-01-01

    The permafrost degradation is the fundamental cause generating embankment diseases and pavement diseases in permafrost region while the permafrost degradation is related with temperature. Based on the field monitoring results of ground temperature along G214 Highway in high temperature permafrost regions, both the ground temperatures in superficial layer and the annual average temperatures under the embankment were discussed, respectively, for concrete pavements and asphalt pavements. The maximum depth of temperature field under the embankment for concrete pavements and asphalt pavements was also studied by using the finite element method. The results of numerical analysis indicate that there were remarkable seasonal differences of the ground temperatures in superficial layer between asphalt pavement and concrete pavement. The maximum influencing depth of temperature field under the permafrost embankment for every pavement was under the depth of 8 m. The thawed cores under both embankments have close relation with the maximum thawed depth, the embankment height, and the service time. The effective measurements will be proposed to keep the thermal stabilities of highway embankment by the results. PMID:24027444

  2. Spills on Flat Inclined Pavements

    SciTech Connect

    Simmons, Carver S.; Keller, Jason M.; Hylden, Jeff L.

    2004-03-01

    This report describes the general spill phenomenology for liquid spills occurring on relatively impermeable surfaces such as concrete or asphalt pavement and the development and application of a model to describe the time evolution of such spills. The discussion assumes evaporation and degradation are negligible and a homogeneous surface. In such an instance, the inherent interfacial properties determine the spatial extent of liquid spreading with the initial flow being controlled by the release rate of the spill and by the liquids resistance to flow as characterized by its viscosity. A variety of spill scenarios were simulated and successful implementation of the model was achieved. A linear relationship between spill area and spill volume was confirmed. The simulations showed spill rate had little effect on the final spill area. Slope had an insignificant effect on the final spill area, but did modify spill shape considerably. However, a fluid sink on the edge of the simulation domain, representing a storm drain, resulted in a substantial decrease in spill area. A bona fide effort to determine the accuracy of the model and its calculations remain, but comparison against observations from a simple experiment showed the model to correctly determine the spill area and general shape under the conditions considered. Further model verification in the form of comparison against small scale spill experiments are needed to confirm the models validity.

  3. 46 CFR 69.111 - Between-deck tonnage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... complete deck runs in a continuous line from stem to stern, the line of the uppermost complete deck is the... different levels from stem to stern, the line of the uppermost complete deck is the longitudinal line of...

  4. 46 CFR 69.111 - Between-deck tonnage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... complete deck runs in a continuous line from stem to stern, the line of the uppermost complete deck is the... different levels from stem to stern, the line of the uppermost complete deck is the longitudinal line of...

  5. A fiber-reinforced composite structure for the repair of thermally cracked bituminous pavements

    NASA Astrophysics Data System (ADS)

    Frantzen, Jeffrey Alan

    1998-10-01

    The apparatus under development in this project is a structural component or beam fabricated from a fiber reinforced plastic composite (FRPC). The FRPC beam is a structural repair component intended to bridge a deteriorated thermal crack in full depth bituminous pavements or partial depth bituminous pavements over portland cement concrete. The bridging action provided by the FRPC beam is intended to minimize roughness through the repaired area for up to five years, eliminate reappearance of the deteriorated crack, and provide a controlled expansion crack that can be treated with standard sealing techniques. This apparatus is designed for maintenance use as a field expedient, semi-permanent repair using tools that are commonly available at the Area Maintenance level. Three FRPC beams were constructed for field trial in a thermally cracked, full depth bituminous pavement on US-36 east of Hiawatha, Kansas. Each of the beams were instrumented with bonded metal foil strain gages and field installation by KDOT Maintenance forces was done in August and September of 1997. The FRPC beams have been evaluated since installation and this evaluation will continue for up to five years. Evaluation of the beams has been accomplished through static load tests using the strain gage instrumentation and Falling Weight Deflectometer measurements. The FRPC beams have performed satisfactorily as of the date of writing.

  6. 17. Baltimore through truss steel bridge (1905), built by the ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    17. Baltimore through truss steel bridge (1905), built by the American Bridge Company. The bridge is 15 to 20 feet wide, with a wooden deck, and connects the Sullivan Machine Co. with the Foundry. The enclosed bridge in the background was constructed ca. 1920, and connects the Chain Machine Building with its power plant, foundry, and pattern shop. - Sullivan Machinery Company, Main Street between Pearl & Water Streets, Claremont, Sullivan County, NH

  7. 58. MISSISSIPPI, NOXUBEE CO. MACON MAHORNER'S BRIDGE, 1884, Ms. 14, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    58. MISSISSIPPI, NOXUBEE CO. MACON MAHORNER'S BRIDGE, 1884, Ms. 14, E 6.5 mi. to McLeod, 4.5 miles S on McLeod-Shuqualak road. Mahorner's bridge (1884). Lower panel point, west span. View is at right-angles to the bridge and from below deck level. show pin connection, floor beams, and stringers. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  8. 12. DETAIL VIEW OF BRIDGE, SHOWING SPRING LINE OF SPANS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. DETAIL VIEW OF BRIDGE, SHOWING SPRING LINE OF SPANS FROM CROWN OF MID-CHANNEL PIER, PAIRED COLUMNS SUPPORTING DECK, ARCHED WINDOW RAILING, LOOKING WEST-NORTHWEST FROM EUREKA SOUTHERN RAILROAD BRIDGE. CABLES VISIBLE IN BACKGROUND ARE EARTHQUAKE RESTRAINERS RETROFITTED TO 1952 HIGHWAY BRIDGE, WHICH FUNCTIONED AS DESIGNED IN APRIL 1992 TEMBLOR - Van Duzen River Bridge, Spanning Van Duzen River at CA State Highway 101, Alton, Humboldt County, CA

  9. Pavement Sealcoat, PAHs, and the Environment

    NASA Astrophysics Data System (ADS)

    Van Metre, P. C.; Mahler, B. J.

    2011-12-01

    Recent research by the USGS has identified coal-tar-based pavement sealants as a major source of polycyclic aromatic hydrocarbons (PAHs) to the environment. Coal-tar-based sealcoat is commonly used to coat parking lots and driveways and is typically is 20-35 percent coal tar pitch, a known human carcinogen. Several PAHs are suspected mutagens, carcinogens, and (or) teratogens. In the central and eastern U.S. where the coal-tar-based sealants dominate use, sum-PAH concentration in dust particles from sealcoated pavement is about 1,000 times higher than in the western U.S. where the asphalt-based formulation is prevalent. Source apportionment modeling indicates that particles from sealcoated pavement are contributing the majority of the PAHs to recent lake sediment in 35 U.S. urban lakes and are the primary cause of upward trends in PAHs in many of these lakes. Mobile particles from parking lots with coal-tar-based sealcoat are tracked indoors, resulting in elevated PAH concentrations in house dust. In a recently completed study, volatilization fluxes of PAHs from sealcoated pavement were estimated to be about 60 times fluxes from unsealed pavement. Using a wide variety of methods, the author and colleagues have shown that coal-tar-based sealcoat is a major source of PAHs to the urban environment and might pose risks to aquatic life and human health.

  10. Performance of pavements designed with low-cost materials

    NASA Astrophysics Data System (ADS)

    Grau, R. W.; Yrjanson, W. A.; Packard, R. G.; Barksdale, R. D.; Potts, C. F.; Ruth, B. E.; Smith, L. L.; Huddleston, I. J.; Vinson, T. S.; Hicks, R. G.

    1980-04-01

    The following areas are discussed. Utilization of marginal aggregate materials for secondary road surface layers; econocrete pavements; current practices; construction and performance of sand-asphalt bases and performance of sand-asphalt and limerock pavements in Florida. Cement stabilization of degrading aggregates use of crushed stone screenings in highway construction (abridgement); and sulfur-asphalt pavement technology are also reviewed.

  11. 46 CFR 169.327 - Deck rails.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Deck rails. 169.327 Section 169.327 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Rails and Guards 169.327 Deck rails. (a) All rails or lifelines must be at least 30 inches...

  12. 46 CFR 169.327 - Deck rails.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Deck rails. 169.327 Section 169.327 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Rails and Guards 169.327 Deck rails. (a) All rails or lifelines must be at least 30 inches...

  13. 46 CFR 169.327 - Deck rails.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Deck rails. 169.327 Section 169.327 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Rails and Guards 169.327 Deck rails. (a) All rails or lifelines must be at least 30 inches...

  14. 46 CFR 169.327 - Deck rails.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Deck rails. 169.327 Section 169.327 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Rails and Guards 169.327 Deck rails. (a) All rails or lifelines must be at least 30 inches...

  15. 46 CFR 177.900 - Deck rails.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... simultaneously. (c) Where space limitations make deck rails impractical for areas designed for crew use only.... (2) Rails on a vessel subject to the 1966 International Convention on Load Lines must be at least 1... installed between a top rail required by paragraph (a) of this section, and the deck so that no open...

  16. 46 CFR 177.900 - Deck rails.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... simultaneously. (c) Where space limitations make deck rails impractical for areas designed for crew use only.... (2) Rails on a vessel subject to the 1966 International Convention on Load Lines must be at least 1... installed between a top rail required by paragraph (a) of this section, and the deck so that no open...

  17. 46 CFR 177.900 - Deck rails.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... simultaneously. (c) Where space limitations make deck rails impractical for areas designed for crew use only.... (2) Rails on a vessel subject to the 1966 International Convention on Load Lines must be at least 1... installed between a top rail required by paragraph (a) of this section, and the deck so that no open...

  18. 46 CFR 169.327 - Deck rails.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Deck rails. 169.327 Section 169.327 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS Construction and Arrangement Rails and Guards § 169.327 Deck rails. (a) All rails or lifelines must be at least 30 inches...

  19. Commander Brand sleeps on aft flight deck

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Commander Brand, with hands folded in front of his chest, sleeps on aft flight deck. Brand's head is just above aft flight deck floor with his back to onorbit station panels. The back and feet of a second crewmember appear next to Brand.

  20. Pavement thickness, surface evenness and construction practice

    NASA Astrophysics Data System (ADS)

    McLellan, J. C.

    1982-01-01

    The structural performance and the riding quality of a road are strongly influenced by the accurate and uniform laying of the pavement materials to the appropriate design thickness. The effectiveness of level control procedures used in road construction to achieve the required thicknesses and surface regularity is investigated. Surface profile and of thickness of pavement were measured during construction on 38 randomly selected 100-meter lengths from two flexible and three rigid roads. Measurements analysis showed that the mean layer thicknesses were generally at or near the required thickness but that layer thickness varied considerably along the test lengths, particularly for the concrete pavements. On flexible roads, the results showed that the profiles of the lower layers influenced the evenness of the finished surface. On rigid construction the evenness of the finished surfaces was independent of the profile of the subbase.

  1. Design of airport pavements for expansive soils

    NASA Astrophysics Data System (ADS)

    McKeen, R. G.

    1981-01-01

    Expansive soil subgrades exhibit volume changes with variation in moisture condition. These changes result in differential movement of airport pavements resting on these soils. Special design procedures must be used to account for the expansive soil activity during equilibration. In addition, special precautions are required to protect the subgrade from moisture variation with climate. Measurement of soil suction is a key step in quantifying moisture-induced soil behavior. Procedures are outlined for suction characterization of the soil and for estimating the in situ differential movement likely to occur under the pavement. Once the wavelength and amplitude characteristics of the differential movement are obtained, design calculations to select the thickness and materials for the pavement may proceed.

  2. Pavement snow melting in Klamath Falls - rehabilitation of the ODOT Well

    SciTech Connect

    Thurston, R.E.; Culver, G.; Lund, J.W.

    1995-02-01

    This paper discusses the use of geothermal energy in pavement de-icing in Klamath Falls, Oregon. Due to a change in traffic routing in 1948, U.S. Highway 97 was routed with a new bridge and roadway through downtown Klamath Falls with an adverse 8 percent grade. Problems with traffic in winter led to the incorporation of a geothermal experiment in de-icing into the Oregon Department of Transportation (ODOT) construction project. The geothermal well was originally artesian, but the static water level has dropped over the years of usage, and the water temperatures at various depths have also dropped. Changes in city environmental regulations in 1985 have called for the elimination of all surface and sewer discharge from geothermal wells. Modifications to the existing pavement de-icing system which would bring it into compliance with the city ordinances are discussed in this paper.

  3. Micro-thermal stress analysis of cement based pavement composite

    SciTech Connect

    Li, G.; Zhao, Y.; Pang, S.S.; Huang, W.

    1998-12-31

    A four-layer sphere model for microscopic thermal analysis was proposed based upon the structural form of cement based pavement composites. Using temperature induced stresses of pavement structure as the external field, the micro-thermal stresses of two types of cement based pavement composite were calculated. The results showed that, by introducing the low stiffness rubberized asphalt in the interphase of coarse aggregate phase and cement mortar phase of Portland cement concrete, the interfacial thermal stresses could be reduced significantly, thus improving crack resistance of the pavement material under low temperature environment. Factors affecting micro-thermal stress of cement based pavement composite were discussed.

  4. Summit Panorama with Rover Deck

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Summit Panorama with Rover (QTVR)

    The panoramic camera on NASA's Mars Exploration Rover Spirit took the hundreds of images combined into this 360-degree view, the 'Husband Hill Summit' panorama. The images were acquired on Spirit's sols 583 to 586 (Aug. 24 to 27, 2005), shortly after the rover reached the crest of 'Husband Hill' inside Mars' Gusev Crater. This is the largest panorama yet acquired from either Spirit or Opportunity. The panoramic camera shot 653 separate images in 6 different filters, encompassing the rover's deck and the full 360 degrees of surface rocks and soils visible to the camera from this position. This is the first time the camera has been used to image the entire rover deck and visible surface from the same position. Stitching together of all the images took significant effort because of the large changes in resolution and parallax across the scene.

    The image is an approximately true-color rendering using the 750-nanometer, 530-nanometer and 480-nanometer filters for the surface, and the 600-nanometer and 480-nanometer filters for the rover deck. Image-to-image seams have been eliminated from the sky portion of the mosaic to better simulate the vista a person standing on Mars would see.

    This panorama provided the team's first view of the 'Inner Basin' region (center of the image), including the enigmatic 'Home Plate' feature seen from orbital data. After investigating the summit area, Spirit drove downhill to get to the Inner Basin region. Spirit arrived at the summit from the west, along the direction of the rover tracks seen in the middle right of the panorama. The peaks of 'McCool Hill' and 'Ramon Hill' can be seen on the horizon near the center of the panorama. The summit region itself is a broad, windswept plateau. Spirit spent more than a month exploring the summit region, measuring the chemistry and mineralogy of soils and rocky outcrops at the peak of Husband Hill for comparison with similar measurements obtained during the ascent.

  5. 15. 'Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. 'Concrete Bridge Over Salt River, Port Kenyon, Humboldt County, California, A.J. Logan, County Surveyor, H.J. Brunnier, Consulting Engineer, March 7, 1919,' showing general plan, plan of top chord, elevation of main girder, transverse section, plan section at deck level. - Salt River Bridge, Spanning Salt River at Dillon Road, Ferndale, Humboldt County, CA

  6. Review on antibacterial characteristics of bridge engineering biomaterials.

    PubMed

    Zhao, Qing-Qing; Chen, Meng-Yao; He, Rui-Lin; Zhang, Zhong-Feng; Ashraf, Muhammad Aqeel

    2016-01-01

    This review summarizes the research on timber construction materials used in bridge construction. It focuses on the application of antiseptic treatments and the use of timber engineering materials in decks and bridges. This review also provides an overview on the future research and prospects of engineered timber materials. PMID:26858558

  7. Review on antibacterial characteristics of bridge engineering biomaterials

    PubMed Central

    Zhao, Qing-qing; Chen, Meng-yao; He, Rui-lin; Zhang, Zhong-feng; Ashraf, Muhammad Aqeel

    2015-01-01

    This review summarizes the research on timber construction materials used in bridge construction. It focuses on the application of antiseptic treatments and the use of timber engineering materials in decks and bridges. This review also provides an overview on the future research and prospects of engineered timber materials. PMID:26858558

  8. 30. VIEW OF BRIDGE, LOOKING NORTH TOWARD THE WALKWAY EAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. VIEW OF BRIDGE, LOOKING NORTH TOWARD THE WALKWAY EAST ABUTMENT. THE HORIZONTAL CABLES RUN FROM THE ABUTMENT TO THE QUARTER POINT OF THE WALKWAY DECK. February 1987 - Verde River Sheep Bridge, Spanning Verde River (Tonto National Forest), Cave Creek, Maricopa County, AZ

  9. 15. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING LONGITUDINAL STRINGERS SUPPORTING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. DETAIL OF UNDERSIDE OF BRIDGE, SHOWING LONGITUDINAL STRINGERS SUPPORTING WOODEN DECK AND RESTING ON TRANSVERSE FLOOR BEAMS. DIAGONAL EYE BARS FOR REINFORCEMENT ARE SEEN AT CENTER; VIEW FROM SOUTH BANK. - Mitchell's Mill Bridge, Spanning Winter's Run on Carrs Mill Road, west of Bel Air, Bel Air, Harford County, MD

  10. 15. BRIDGE TENDER ALBERT REEVES OF MAURICETOWN AND HELPER WALLY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. BRIDGE TENDER ALBERT REEVES OF MAURICETOWN AND HELPER WALLY HALES HOLDING HUGE KEY ABOVE HOLE IN DECK OF CENTER SWING SPAN TO REVEAL KEY BASETHE KEY IS SET UPON A MALE FITTING USED TO OPEN THE SPAN - Maurice River Pratt Through-Truss Swing Bridge, Spanning Maurice River, Mauricetown, Cumberland County, NJ

  11. 13. VIEW OF UNDERSIDE OF BRIDGE, SHOWING TENSION RODS, SWAY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. VIEW OF UNDERSIDE OF BRIDGE, SHOWING TENSION RODS, SWAY BRACING TIMBER STRINGERS CARRYING CORRUGATED METAL DECK. LOOKING NORTH-NORTHWEST. 65mm lens - Tule River Hydroelectric Complex, Tule River Bridge, Spanning North Fork of Middle Fork of Tule River, Springville, Tulare County, CA

  12. Porous pavement. Phase 1: Design and operational criteria

    NASA Astrophysics Data System (ADS)

    Diniz, E. V.

    1980-08-01

    Utilization concepts, benefits and disadvantages, as well as other characteristics of porous pavements are presented with emphasis on porous asphalt pavements, but the criteria and design approach are applicable to all other porous pavement types. Design considerations include siting problems, load bearing design and hydrologic design. The history of porous pavement development and previous experience with porous pavement by several designers, contractors and operators are described. A computer model for hydrologic performance evaluation of existing or proposed porous pavement systems is also examined. Load bearing design criteria are based on previous work conducted for porous asphalt pavements. Appendices include a sample set of specifications for porous asphalt construction and a list of soils and their permeability classes as prepared by the U.S. Soil Conservation Service.

  13. Quantitative analysis of microtubule orientation in interdigitated leaf pavement cells.

    PubMed

    Akita, Kae; Higaki, Takumi; Kutsuna, Natsumaro; Hasezawa, Seiichiro

    2015-01-01

    Leaf pavement cells are shaped like a jigsaw puzzle in most dicotyledon species. Molecular genetic studies have identified several genes required for pavement cells morphogenesis and proposed that microtubules play crucial roles in the interdigitation of pavement cells. In this study, we performed quantitative analysis of cortical microtubule orientation in leaf pavement cells in Arabidopsis thaliana. We captured confocal images of cortical microtubules in cotyledon leaf epidermis expressing GFP-tubulinβ and quantitatively evaluated the microtubule orientations relative to the pavement cell growth axis using original image processing techniques. Our results showed that microtubules kept parallel orientations to the growth axis during pavement cell growth. In addition, we showed that immersion treatment of seed cotyledons in solutions containing tubulin polymerization and depolymerization inhibitors decreased pavement cell complexity. Treatment with oryzalin and colchicine inhibited the symmetric division of guard mother cells. PMID:26039484

  14. Quantitative analysis of microtubule orientation in interdigitated leaf pavement cells

    PubMed Central

    Akita, Kae; Higaki, Takumi; Kutsuna, Natsumaro; Hasezawa, Seiichiro

    2015-01-01

    Leaf pavement cells are shaped like a jigsaw puzzle in most dicotyledon species. Molecular genetic studies have identified several genes required for pavement cells morphogenesis and proposed that microtubules play crucial roles in the interdigitation of pavement cells. In this study, we performed quantitative analysis of cortical microtubule orientation in leaf pavement cells in Arabidopsis thaliana. We captured confocal images of cortical microtubules in cotyledon leaf epidermis expressing GFP-tubulinβ and quantitatively evaluated the microtubule orientations relative to the pavement cell growth axis using original image processing techniques. Our results showed that microtubules kept parallel orientations to the growth axis during pavement cell growth. In addition, we showed that immersion treatment of seed cotyledons in solutions containing tubulin polymerization and depolymerization inhibitors decreased pavement cell complexity. Treatment with oryzalin and colchicine inhibited the symmetric division of guard mother cells. PMID:26039484

  15. Studies of the effect of aging of ``quiet'' pavements on tire/pavement noise

    NASA Astrophysics Data System (ADS)

    Reyff, James A.; Donavan, Paul

    2005-09-01

    One of the issues with using quieter pavements to abate traffic noise is their continued acoustic performance over the life cycle of the surface. Aging effects can be assessed in two manners: (1) long term monitoring of the noise performance of an individual section of roadway; (2) measurement of multiple sections of pavement of the same construction, but different ages. Long term monitoring of Interstate 80 near Davis (I-80 Davis) began in 1998, just prior to the placement of a dense graded leveling course and open graded asphalt overlay. The pavement surface is now approaching 7 years old and continues to show a traffic noise reduction of about 5 dBA over the existing condition. As support of the Arizona Quiet Pavement Program (QPPP), similarly constructed sections of asphalt rubber friction course (ARFC) on Arizona's interstate highways were measured for tire/pavement performance using the close proximity (CPX) method and the on-board sound intensity method. The construction dates for the pavements ranged from 1988 to 1999. The total range in noise level was 7 dB with some indication of degrading performance with age.

  16. Permeable pavement research Edison, New Jersey

    EPA Science Inventory

    These are the slides for the New York City Concrete Promotional Council Pervious Concrete Seminar presentation. The basis for the project, the monitoring design and some preliminary monitoring data from the permeable pavement parking lot at the Edison Environmental Center are pre...

  17. 46 CFR 116.1110 - Drainage of flush deck vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Drainage of flush deck vessels. 116.1110 Section 116... ARRANGEMENT Drainage and Watertight Integrity of Weather Decks 116.1110 Drainage of flush deck vessels. (a... watertight and have no obstruction to overboard drainage. (b) Each flush deck vessel may have solid...

  18. 26. Photocopy of 1968 repair drawing for 'WalpoleWestminster Bridge Over: ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. Photocopy of 1968 repair drawing for 'Walpole-Westminster Bridge Over: Connecticut River', unattributed. (Filed with N.H. Department of Transportation, Bridge Design Division plan archives, Concord, N.H.) Sheet: Deck and Expansion Joint Details June 13, 1968 - Walpole-Westminster Bridge, Spanning Connecticut River between Walpole, NH & Westminster, VT, Walpole, Cheshire County, NH

  19. 4. VIEW OF GEORGIA DOT BRIDGE NO. 05100025D01986N (JAMES P. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. VIEW OF GEORGIA DOT BRIDGE NO. 051-00025D-01986N (JAMES P. HOULIHAN BRIDGE) FACING EAST SHOWING STEEL GRID DECKING. OPERATOR'S HOUSE LOCATED ON UPPER SECTION OF TRUSS. - Georgia DOT Bridge No. 051-00025D-01986N, US 17 & State Route 25 Spanning Savannah River, Port Wentworth, Chatham County, GA

  20. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Hydraulic system for the Generic Flight Deck (GFD) Simulator located in the Cockpit Motion Facility. The hydraulics are a necessary component to perform a model test on simulator structures. Photographed in building 1268D.

  1. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Close up of the sensors for the Generic Flight Deck (GFD) Simulator located in the Cockpit Motion Facility. The sensors are a necessary component to perform a model test on simulator structures. Photographed in building 1268D.

  2. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Sensors for the Generic Flight Deck (GFD) Simulator located in the Cockpit Motion Facility. The sensors are a necessary component to perform a model test on simulator structures. Photographed in building 1268D.

  3. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The hydraulic valve system for the Generic Flight Deck (GFD) Simulator - located in the Cockpit Motion Facility. The hydraulics are necessary to perform a model test on simulator structures. Photographed in building 1268D.

  4. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    A sensor for the Generic Flight Deck (GFD) Simulator - located in the Cockpit Motion Facility. The sensors are necessary to perform a model test on simulator structures. Photographed in building 1268D.

  5. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Computers used for the Generic Flight Deck (GFD) Simulator - located in the Cockpit Motion Facility. The computer system is necessary to perform a model test on simulator structures. Photographed in building 1268D.

  6. CMF/Generic Flight Deck - model test

    NASA Technical Reports Server (NTRS)

    1999-01-01

    The hydraulic system for the Generic Flight Deck (GFD) Simulator - located in the Cockpit Motion Facility. The hydraulics are necessary to perform a model test on simulator structures. Photographed in building 1268D.

  7. Definition of the 2005 flight deck environment

    NASA Technical Reports Server (NTRS)

    Alter, K. W.; Regal, D. M.

    1992-01-01

    A detailed description of the functional requirements necessary to complete any normal commercial flight or to handle any plausible abnormal situation is provided. This analysis is enhanced with an examination of possible future developments and constraints in the areas of air traffic organization and flight deck technologies (including new devices and procedures) which may influence the design of 2005 flight decks. This study includes a discussion on the importance of a systematic approach to identifying and solving flight deck information management issues, and a description of how the present work can be utilized as part of this approach. While the intent of this study was to investigate issues surrounding information management in 2005-era supersonic commercial transports, this document may be applicable to any research endeavor related to future flight deck system design in either supersonic or subsonic airplane development.

  8. Resource management on the flight deck. [conferences

    NASA Technical Reports Server (NTRS)

    Cooper, G. E. (Editor); White, M. D. (Editor); Lauber, J. K. (Editor)

    1980-01-01

    Several approaches to the training and selection of aircrew are presented including both industry and nonindustry perspectives. Human factor aspects of the problem are also examined with specific emphasis on the psychology of the flight deck situation.

  9. Work on Phoenix Science Deck

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Lockheed Martin Space Systems technicians Jim Young (left) and Jack Farmerie (right) work on the science deck of NASA's Phoenix Mars Lander.

    The spacecraft was built in a 100,000-class clean room near Denver under NASA's planetary protection practices to keep organics from being taken to Mars. The lander's robotic arm, built by the Jet Propulsion Laboratory, Pasadena, is seen at the top of the picture. The color and grey dots will be used to calibrate the spacecraft's Surface Stereoscopic Imager camera once the spacecraft has landed on the red planet.

    The Phoenix mission is led by Principal Investigator Peter H. Smith of the University of Arizona, Tucson, with project management at NASA's Jet Propulsion Laboratory and development partnership with Lockheed Martin Space Systems. International contributions for Phoenix are provided by the Canadian Space Agency, the University of Neuchatel (Switzerland), the University of Copenhagen, and the Max Planck Institute in Germany. JPL is a division of the California Institute of Technology in Pasadena.

  10. The impact of material characteristics on tire pavement interaction noise for flexible pavements

    NASA Astrophysics Data System (ADS)

    Kocak, Salih

    Noise pollution has recently been one of the growing problems all over the world. While there are many sources of the noise, traffic noise is the main contributor to the total environmental noise. Although there are different sources for traffic noise, the tire pavement interaction noise is the most dominant component within most city and highway limits. One of the ways to reduce the tire pavement noise is to improve the material characteristics of the pavements such that they produce less noise. In this study, the relationship between basic material characteristics (e.g., Hot Mix Asphalt (HMA) volumetrics) and sound generation and absorption characteristics of flexible pavements was investigated. In addition, the effect of linear visco-elastic properties (e.g., dynamic modulus (|E*|) and phase angle (delta)) on sound absorption was studied. In order to focus only on impact of material characteristics and overshadow the effect of surface texture, a novel laboratory tire pavement noise measurement simulator (TIPANOS) was developed. The statistical analysis results showed that although the individual material characteristics do not have appreciable influence on sound absorption, there is a significant correlation between sound pressure levels (SPL) and combination of several material and linear visco-elastic parameters.

  11. Molecular mechanisms controlling pavement cell shape in Arabidopsis leaves.

    PubMed

    Qian, Pingping; Hou, Suiwen; Guo, Guangqin

    2009-08-01

    Pavement cells have an interlocking jigsaw puzzle-shaped leaf surface pattern. Twenty-three genes involved in the pavement cell morphogenesis were discovered until now. The mutations of these genes through various means lead to pavement cell shape defects, such as loss or lack of interdigitation, the reduction of lobing, gaps between lobe and neck regions in pavement cells, and distorted trichomes. These phenotypes are affected by the organization of microtubules and microfilaments. Microtubule bands are considered corresponding with the neck regions of the cell, while lobe formation depends on patches of microfilaments. The pathway of Rho of plant (ROP) GTPase signaling cascades regulates overall activity of the cytoskeleton in pavement cells. Some other proteins, in addition to the ROPs, SCAR/WAVE, and ARP2/3 complexes, are also involved in the pavement cell morphogenesis. PMID:19529941

  12. Stochastic finite element applications in rigid pavement performance

    NASA Astrophysics Data System (ADS)

    Attoh-Okine, Nii O.

    1999-05-01

    Rigid pavement structures have uncertainties and variability in their structural layers and components. These variations and uncertainties are seldomly included in performance assessment and evaluation in pavement systems. This paper proposes to use Stochastic Finite Element Method (SFEM) in rigid pavement faulting and load transfer efficiency. The SFEM uses random parameters, as stochastic process namely random fields. These random fields are characterized, quantitatively by spatial functions of statistical moment like the mean, variance and covariance.

  13. Effectiveness of transverse grooves in rigid pavement

    NASA Astrophysics Data System (ADS)

    Gurney, G. F.; Bryden, J. E.

    1982-10-01

    Transverse grooves were installed at 11 intersection approaches on worn rigid pavement to reduce a high rate of wet road accidents. In most cases, accident reductions were experienced only at intersections with multiple negative operational characteristics, including higher approach speeds, limited sight distances, and frequent vehicle stopping for turns or stop signs. Intersections with no more than one negative characteristic generally did not benefit from grooving.

  14. Modeling and experimental testing of a smart composite bridge

    NASA Astrophysics Data System (ADS)

    Chandrashekhara, K.; Nanni, Antonio; Watkins, Steve E.; Kumar, Prakash

    2003-10-01

    An all composite bridge with integral sensor network has been designed and built at the University of Missouri-Rolla (UMR). An extensive experimental study and finite element analysis were carried out to obtain and compare properties (stiffness, strength, failure modes) of 76 mm (3 in) square hollow pultruded Fiber Reinforced Polymer (FRP) tubes and their assemblies. Tube assemblies were used in the fabrication of bridge deck designed for H-20 truckloads as specified by the American Association of State Highway and Transportation Officials (AASHTO). The bridge is 9.14 m (30 ft) long and is 2.74 m (9 ft) wide. All the coupons were tested under three- or four-point bending. Experimental results show excellent linear elastic behavior up to failure and are in good agreement with finite element solutions. A quarter portion of the full-sized bridge deck was then tested for its structural performance under design and fatigue loading and also for ultimate load capacity to evaluate the bridge response. The characteristics of the full-size bridge deck were determined by analyzing the performed tests. The test sample showed almost no reduction in stiffness or strength after 2 million cycles of fatigue loading in excess of the design load. The bridge was installed at the UMR campus in July 2000. The bridge is equipped with fiber optic sensors, and the response of the bridge will be remotely monitored.

  15. Proceedings of the Continuously Reinforced Concrete Pavement workshop

    NASA Astrophysics Data System (ADS)

    1980-06-01

    Design, construction, and maintenance procedures of continuously reinforced concrete pavements are dicussed. Maintenance procedures were emphasized. Polymer patching, under sealing, and flexible and rigid overlays were considered.

  16. Hybrid green permeable pave with hexagonal modular pavement systems

    NASA Astrophysics Data System (ADS)

    Rashid, M. A.; Abustan, I.; Hamzah, M. O.

    2013-06-01

    Modular permeable pavements are alternatives to the traditional impervious asphalt and concrete pavements. Pervious pore spaces in the surface allow for water to infiltrate into the pavement during rainfall events. As of their ability to allow water to quickly infiltrate through the surface, modular permeable pavements allow for reductions in runoff quantity and peak runoff rates. Even in areas where the underlying soil is not ideal for modular permeable pavements, the installation of under drains has still been shown to reflect these reductions. Modular permeable pavements have been regarded as an effective tool in helping with stormwater control. It also affects the water quality of stormwater runoff. Places using modular permeable pavement has been shown to cause a significant decrease in several heavy metal concentrations as well as suspended solids. Removal rates are dependent upon the material used for the pavers and sub-base material, as well as the surface void space. Most heavy metals are captured in the top layers of the void space fill media. Permeable pavements are now considered an effective BMP for reducing stormwater runoff volume and peak flow. This study examines the extent to which such combined pavement systems are capable of handling load from the vehicles. Experimental investigation were undertaken to quantify the compressive characteristics of the modular. Results shows impressive results of achieving high safety factor for daily life vehicles.

  17. Study on Flexible Pavement Failures in Soft Soil Tropical Regions

    NASA Astrophysics Data System (ADS)

    Jayakumar, M.; Chee Soon, Lee

    2015-04-01

    Road network system experienced rapid upgrowth since ages ago and it started developing in Malaysia during the colonization of British due to its significant impacts in transportation field. Flexible pavement, the major road network in Malaysia, has been deteriorating by various types of distresses which cause descending serviceability of the pavement structure. This paper discusses the pavement condition assessment carried out in Sarawak and Sabah, Malaysia to have design solutions for flexible pavement failures. Field tests were conducted to examine the subgrade strength of existing roads in Sarawak at various failure locations, to assess the impact of subgrade strength on pavement failures. Research outcomes from field condition assessment and subgrade testing showed that the critical causes of pavement failures are inadequate design and maintenance of drainage system and shoulder cross fall, along with inadequate pavement thickness provided by may be assuming the conservative value of soil strength at optimum moisture content, whereas the exiting and expected subgrade strengths at equilibrium moisture content are far below. Our further research shows that stabilized existing recycled asphalt and base materials to use as a sub-base along with bitumen stabilized open graded base in the pavement composition may be a viable solution for pavement failures.

  18. A study of bituminous pavements to determine a correlation between pavement structure designs and tripping of asphalt cement

    NASA Astrophysics Data System (ADS)

    Barton, B. R.

    1984-03-01

    After detecting a few cases of stripping of asphalt cement from the aggregate in bituminous pavement, there was concern that stripping might be a widespread problem in the state. It is agreed that water is the cause of stripping, and it was the opinion of some that pavements on granular bases would be less likely to strip because of supposedly better drainage characteristics. Differently designed pavement structures in all areas of the state were investigated to determine if there is a correlation between base and pavement design and stripping. Stripping was not as widespread as had been feared and there was less stripping in fulldepth bituminous base and pavement constructed over a lime-treated subgrade than in pavements constructed oer granular bases. This was contrary to what some had theorized.

  19. Multimodal approach to seismic pavement testing

    USGS Publications Warehouse

    Ryden, N.; Park, C.B.; Ulriksen, P.; Miller, R.D.

    2004-01-01

    A multimodal approach to nondestructive seismic pavement testing is described. The presented approach is based on multichannel analysis of all types of seismic waves propagating along the surface of the pavement. The multichannel data acquisition method is replaced by multichannel simulation with one receiver. This method uses only one accelerometer-receiver and a light hammer-source, to generate a synthetic receiver array. This data acquisition technique is made possible through careful triggering of the source and results in such simplification of the technique that it is made generally available. Multiple dispersion curves are automatically and objectively extracted using the multichannel analysis of surface waves processing scheme, which is described. Resulting dispersion curves in the high frequency range match with theoretical Lamb waves in a free plate. At lower frequencies there are several branches of dispersion curves corresponding to the lower layers of different stiffness in the pavement system. The observed behavior of multimodal dispersion curves is in agreement with theory, which has been validated through both numerical modeling and the transfer matrix method, by solving for complex wave numbers. ?? ASCE / JUNE 2004.

  20. Calculations in bridge aeroelasticity via CFD

    SciTech Connect

    Brar, P.S.; Raul, R.; Scanlan, R.H.

    1996-12-31

    The central focus of the present study is the numerical calculation of flutter derivatives. These aeroelastic coefficients play an important role in determining the stability or instability of long, flexible structures under ambient wind loading. A class of Civil Engineering structures most susceptible to such an instability are long-span bridges of the cable-stayed or suspended-span variety. The disastrous collapse of the Tacoma Narrows suspension bridge in the recent past, due to a flutter instability, has been a big impetus in motivating studies in flutter of bridge decks.

  1. A modular steel freeway bridge: design concept and earthquake resistance.

    PubMed

    Wattenburg, W H; McCallen, D B; Murray, R C

    1995-04-14

    A modular multilane steel freeway bridge has been constructed from surplus railroad flatcar decks. It can be erected on-site in a few days' time. It has been built and static-load tested for emergency freeway bridge repair. This inexpensive modular bridge may also have broad application around the world for low-cost bridges in areas where funds are limited. On the basis of static-load testing performed by the California Department of Transportation and computer dynamic analysis, this simple modular-design concept has the potential of providing a strong bridge that can withstand the severe aftershocks expected immediately after a major earthquake. PMID:17814794

  2. Wave impact on a deck or baffle

    NASA Astrophysics Data System (ADS)

    Md Noar, Nor Aida Zuraimi; Greenhow, Martin

    2015-02-01

    Some coastal or ocean structures have deck-like baffles or horizontal platforms that can be exposed to wave action in heavy seas. A similar situation may occur in partially-filled tanks with horizontal baffles that become engulfed by sloshing waves. This can result in dangerous wave impact loads (slamming) causing a rapid rise of pressures which may lead to local damaging by crack initiation and/or propagation. We consider the wave impact against the whole of underside of horizontal deck (or baffle) projecting from a seawall (or vertical tank wall), previously studied by Wood and Peregrine (1996) using a different method based on conformal mappings. The approach used is to simplify the highly time-dependent and very nonlinear problem by considering the time integral of the pressure over the duration of the impact pressure-impulse, P (x, y). Our method expresses this in terms of eigenfunctions that satisfy the boundary conditions apart from that on the impact region and the matching of the two regions (under the platform and under the free surface); this results in a matrix equation to be solved numerically. As in Wood and Peregrine, we found that the pressure impulse on the deck increases when the length of deck increases, there is a strong pressure gradient beneath the deck near the seaward edge and the maximum pressure impulse occurs at the landward end of the impact zone.

  3. Two-decked nature of the Ouachita Mountains, Arkansas

    NASA Astrophysics Data System (ADS)

    Babaei, Abdolali; Viele, George W.

    1992-11-01

    The Ouachita Mountains of Arkansas and Oklahoma are made up of two structural decks. The lower deck of tight to isoclinal folds in pre-Middle Mississippian strata records multiple folding and low-grade metamorphism. The upper deck of open folds in Carboniferous rocks shows no evidence of the multiple folding and metamorphism. Dips of fold limbs in the lower deck are typically more than 60°; dips of fold limbs in the upper deck are generally less than 45°; fold wavelengths in the lower deck are in the range of 0.5 to 3.5 km; fold wavelengths in the upper deck are generally in the range of 12 to 15 km. Estimates of shortening of the folds in the lower deck are five times greater than those of shortening of the upper deck. The change from tight folding to broad folding takes place in the middle part of the Mississippian Stanley Group. The difference in fold style has been attributed to disharmonic folding of a stiff upper deck and a ductile lower deck. However, the boundary between harmonic and disharmonic folds shows no apparent relation to the fold wavelength or the stratigraphic spacing of stiff beds. We hypothesize that the difference in structural style reflects the unconformable deposition of younger folded and faulted foreland-basin strata (the upper deck) over the older lower deck strata, which were stacked in an accretionary wedge.

  4. 46 CFR 171.140 - Drainage of a flush deck vessel.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.140 Drainage of a flush deck vessel. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel...

  5. 46 CFR 171.140 - Drainage of a flush deck vessel.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.140 Drainage of a flush deck vessel. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel...

  6. 46 CFR 171.140 - Drainage of a flush deck vessel.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.140 Drainage of a flush deck vessel. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel...

  7. 46 CFR 171.140 - Drainage of a flush deck vessel.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.140 Drainage of a flush deck vessel. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel...

  8. 46 CFR 171.140 - Drainage of a flush deck vessel.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... PERTAINING TO VESSELS CARRYING PASSENGERS Drainage of Weather Decks § 171.140 Drainage of a flush deck vessel. (a) Except as provided in paragraph (b) of this section, the weather deck on a flush deck vessel...

  9. 123. FORWARD PORT VIEW OF THE ISLAND WITH FLIGHT DECK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    123. FORWARD PORT VIEW OF THE ISLAND WITH FLIGHT DECK GUN MOUNTS, TAKEN FROM FORWARD FLIGHT DECK. APRIL 1945, (NATIONAL ARCHIVES NO. 80-G-469299) - U.S.S. HORNET, Puget Sound Naval Shipyard, Sinclair Inlet, Bremerton, Kitsap County, WA

  10. 61. View forward down hurricane deck toward salon clerestory, walking ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    61. View forward down hurricane deck toward salon clerestory, walking beam, stack, and wheelhouse. Second smaller stack is from donkey boiler on main deck. - Ferry TICONDEROGA, Route 7, Shelburne, Chittenden County, VT

  11. Permeable Pavement Demonstration at the Edison Environmental Center (Hartford)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  12. Full-Depth Asphalt Pavements for Parking Lots and Driveways.

    ERIC Educational Resources Information Center

    Asphalt Inst., College Park, MD.

    The latest information for designing full-depth asphalt pavements for parking lots and driveways is covered in relationship to the continued increase in vehicle registration. It is based on The Asphalt Institute's Thickness Design Manual, Series No. 1 (MS-1), Seventh Edition, which covers all aspects of asphalt pavement thickness design in detail,

  13. Permeable pavement demonstration site at Edison Environmental Center (Presentation)

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, working pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are necessa...

  14. Permeable pavement demonstration at the Edison Environmental Center

    EPA Science Inventory

    There are few studies of full-scale, outdoor, replicated, functioning pervious pavement systems. More studies of pervious pavement operating in its intended use (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions, and maintenance regimes are nec...

  15. Electro-optical approach to pavement deflection management

    NASA Astrophysics Data System (ADS)

    Rish, Jeff W., III; Adcock, Avery D.; Tuan, Christopher Y.; Baker, Samuel L.; Welker, Hugh W., II; Johnson, Roger F.

    1995-07-01

    A prototype continuous deflection device, referred to as a rolling weight deflectometer (RWD), has been developed as a nondestructive evaluation tool for airfield pavements. The system consists of a rigid trailer equipped with specially designed optical triangulation pavement sensors, a high-speed data acquisition system, and a high-pressure tire/load platform assembly. Pavement sensors are mounted on a rigid box beam equipped with an internal sensor system that corrects, in real time, the relative pavement height position measurements for displacements induced in the beam by mechanical vibrations, changes in temperature, or nonuniform dynamic loads at points where the beam attaches to the frame. The device produces continuous deflection profiles that show pavement response to a moving loaded wheel along the path of travel. These deflection profiles, combined with multiple passes along a lane, provide a far more detailed picture of the pavement structural integrity than has ever before been possible, because existing evaluation tools only produce response information at discrete points. Preliminary results show deflections measured by the RWD are in general agreement with the expected pavement response for various loads. A discussion of the device configuration, preliminary data, and potential as a pavement management tool is presented.

  16. Permeable Pavement Monitoring at the Edison Environmental Center Demonstration Site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  17. Permeable pavement monitoring at the Edison Environmental Center demonstration site

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used pervious pavement systems. Practitioners need additional studies of pervious pavement systems in its intended application (parking lot, roadway, etc.) during a range of climatic events, daily usage conditions...

  18. Pavement thickness evaluation by GPR survey in Idaho

    NASA Astrophysics Data System (ADS)

    Sener, Joseph C.; Smith, Robert M.; Garz, Michael D.; Murgel, George A.; Hamilton, Robert W.; Haws, David R.

    1998-03-01

    In 1995 and 1996, the Idaho Transportation Department (ITD) conducted a series of ground-penetrating radar (GPR) surveys as a nondestructive testing (NDT) method to evaluate the thickness of asphalt and Portland cement concrete (AC/PCC) pavements in Idaho. GPR surveys employed both air-coupled and combination air and ground coupled systems with their associated equipment and software. A total of 30 miles of AC/PCC pavements were evaluated by GPR surveys. The results obtained were correlated with the site-specific ground-truth data from borings. Knowledge of pavement layer thickness is needed to predict pavement performance, establish load carrying capacities and develop maintenance and rehabilitation priorities. In addition, for new construction, it is important to ensure that the thickness of materials being placed by the contractor is acceptably close to specification. Core sampling and test pits are destructive to the pavement system, expensive, time consuming and intrusive to traffic. The objective of the ITD study was to evaluate, compare and assess the ability of these two GPR systems to accurately measure the thickness of multiple pavement layers, and document the data nondestructively. This paper reviews the findings of these surveys and provides statistically based data for both AC and PCC pavements. The overall study has shown that reasonably accurate, dependable determination of pavement thickness can be achieved by using GPR survey for conditions encountered in Idaho.

  19. Modeling the Hydrologic Processes of a Permeable Pavement System

    EPA Science Inventory

    A permeable pavement system can capture stormwater to reduce runoff volume and flow rate, improve onsite groundwater recharge, and enhance pollutant controls within the site. A new unit process model for evaluating the hydrologic performance of a permeable pavement system has be...

  20. Permeable pavement demonstration at the Edison Environmental Center (Hartford, CT)

    EPA Science Inventory

    In general, there is a lack of full-scale, outdoor, real-world porous pavement studies with system replicates. More studies of porous pavement operating in its intended use (parking lot, roadway, etc.) with climatic events, regular use, and maintenance effects, are necessary. The...

  1. Permeable Pavement Research at the Edison Environmental Center

    EPA Science Inventory

    There are few detailed studies of full-scale, replicated, actively-used permeable pavement systems. Practitioners need additional studies of permeable pavement systems in its intended application (parking lot, roadway, etc.) across a range of climatic events, daily usage conditio...

  2. Nutrient Infiltrate Concentrations from Three Permeable Pavement Types

    EPA Science Inventory

    While permeable pavement is increasingly being used to control stormwater runoff, field-based, side-by-side investigations on the effects different pavement types have on nutrient concentrations present in stormwater runoff are limited. In 2009, the U.S. EPA constructed a 0.4-ha...

  3. Myocardial Bridge

    MedlinePLUS

    ... Sudden Cardiac Arrest Valve Disease Vulnerable Plaque Myocardial Bridge | Share Related terms: myocardium, coronary arteries, myocardial ischemia ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  4. Bridge permeameter

    DOEpatents

    Graf, Darin C.; Warpinski, Norman R.

    1996-01-01

    A system for single-phase, steady-state permeability measurements of porous rock utilizes a fluid bridge arrangement analogous to a Wheatstone bridge. The arms of the bridge contain the sample and calibrated flow resistors.

  5. Standard plans for southern pine bridges. Forest Service general technical report

    SciTech Connect

    Hilbrich Lee, P.D.; Ritter, M.A.; Triche, M.

    1995-09-01

    This publication contains standardized designs and details for three timber bridge superstructure types, including stress-laminated sawn lumber bridges, stress laminated glued laminated timber (glulam) bridges, and longitudinal sawn lumber stringer bridges with transverse plank decks. Each set of plans encompasses numerous span length and width combinations, design loadings for AASHTO HS 20-44 and HS 25-44 vehicles, and two options for live-load deflection criteria.

  6. Monitoring asphalt pavement damages using remote sensing techniques

    NASA Astrophysics Data System (ADS)

    Mettas, Christodoulos; Themistocleous, Kyriacos; Neocleous, Kyriacos; Christofe, Andreas; Pilakoutas, Kypros; Hadjimitsis, Diofantos

    2015-06-01

    One of the main issues in the maintenance plans of road agencies or governmental organizations is the early detection of damaged asphalt pavements. The development of a smart and non-destructive systematic technique for monitoring damaged asphalt pavements is considered a main priority to fill this gap. During the 1970's, remote sensing was used to map road surface distress, while during the last decade, remote sensing became more advanced, thereby assisting in the evolution of the identification and mapping of roads. Various techniques were used in order to explore condition, age, weaknesses and imperfections of asphalted pavements. These methods were fairly successful in the classification of asphalted surfaces and in the detection of some of their characteristics. This paper explores the state of the art of using remote sensing techniques for monitoring damaged pavements and some typical spectral profiles of various asphalt pavements in Cyprus area acquired using the SVC1024 field spectroradiometer.

  7. 14 CFR 125.315 - Admission to flight deck.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Admission to flight deck. 125.315 Section...,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Flight Operations § 125.315 Admission to flight deck. (a) No person may admit any person to the flight deck of an airplane unless...

  8. 14 CFR 121.547 - Admission to flight deck.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Admission to flight deck. 121.547 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.547 Admission to flight deck. (a) No person may admit any person to the flight deck of an aircraft unless the person being...

  9. 14 CFR 121.547 - Admission to flight deck.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Admission to flight deck. 121.547 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.547 Admission to flight deck. (a) No person may admit any person to the flight deck of an aircraft unless the person being...

  10. 14 CFR 121.547 - Admission to flight deck.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Admission to flight deck. 121.547 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.547 Admission to flight deck. (a) No person may admit any person to the flight deck of an aircraft unless the person being...

  11. 14 CFR 121.547 - Admission to flight deck.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Admission to flight deck. 121.547 Section... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Flight Operations § 121.547 Admission to flight deck. (a) No person may admit any person to the flight deck of an aircraft unless the person being...

  12. 14 CFR 125.315 - Admission to flight deck.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Admission to flight deck. 125.315 Section...,000 POUNDS OR MORE; AND RULES GOVERNING PERSONS ON BOARD SUCH AIRCRAFT Flight Operations § 125.315 Admission to flight deck. (a) No person may admit any person to the flight deck of an airplane unless...

  13. 46 CFR 42.13-20 - Deck line.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 2 2011-10-01 2011-10-01 false Deck line. 42.13-20 Section 42.13-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA General Rules for Determining Load Lines 42.13-20 Deck line. (a) The deck line is a horizontal line...

  14. 46 CFR 12.15-13 - Deck engine mechanic.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Deck engine mechanic. 12.15-13 Section 12.15-13 Shipping... ENDORSEMENTS Qualified Member of the Engine Department § 12.15-13 Deck engine mechanic. (a) An applicant for an endorsement as deck engine mechanic shall be a person holding an MMC or MMD endorsed as junior engineer....

  15. 46 CFR 12.15-13 - Deck engine mechanic.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Deck engine mechanic. 12.15-13 Section 12.15-13 Shipping... ENDORSEMENTS Qualified Member of the Engine Department § 12.15-13 Deck engine mechanic. (a) An applicant for an endorsement as deck engine mechanic shall be a person holding an MMC or MMD endorsed as junior engineer....

  16. 46 CFR 12.15-13 - Deck engine mechanic.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Deck engine mechanic. 12.15-13 Section 12.15-13 Shipping... ENDORSEMENTS Qualified Member of the Engine Department § 12.15-13 Deck engine mechanic. (a) An applicant for an endorsement as deck engine mechanic shall be a person holding an MMC or MMD endorsed as junior engineer....

  17. 46 CFR 69.109 - Under-deck tonnage.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...) If the tonnage deck runs in a continuous line from stem to stern, the line of the tonnage deck is the... to one-half of the pitch of the beam down to the upper side of the ordinary frames, floors... are not reduced by measuring to deck-beam brackets. In cases of camber when an upper breadth...

  18. 46 CFR 69.109 - Under-deck tonnage.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...) If the tonnage deck runs in a continuous line from stem to stern, the line of the tonnage deck is the... to one-half of the pitch of the beam down to the upper side of the ordinary frames, floors... are not reduced by measuring to deck-beam brackets. In cases of camber when an upper breadth...

  19. 46 CFR 190.10-45 - Weather deck communications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Weather deck communications. 190.10-45 Section 190.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  20. 46 CFR 72.10-45 - Weather deck communications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 3 2014-10-01 2014-10-01 false Weather deck communications. 72.10-45 Section 72.10-45... ARRANGEMENT Means of Escape § 72.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders. Where ladders are...

  1. 46 CFR 72.10-45 - Weather deck communications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 3 2011-10-01 2011-10-01 false Weather deck communications. 72.10-45 Section 72.10-45... ARRANGEMENT Means of Escape § 72.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders. Where ladders are...

  2. 46 CFR 108.167 - Weather deck ladders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Weather deck ladders. 108.167 Section 108.167 Shipping... EQUIPMENT Construction and Arrangement Means of Escape § 108.167 Weather deck ladders. Each unit must have at least one permanent, inclined ladder between each weather deck. Classified Locations...

  3. 46 CFR 92.10-45 - Weather deck communications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Weather deck communications. 92.10-45 Section 92.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  4. 46 CFR 108.167 - Weather deck ladders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Weather deck ladders. 108.167 Section 108.167 Shipping... EQUIPMENT Construction and Arrangement Means of Escape § 108.167 Weather deck ladders. Each unit must have at least one permanent, inclined ladder between each weather deck. Classified Locations...

  5. 46 CFR 72.10-45 - Weather deck communications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 3 2010-10-01 2010-10-01 false Weather deck communications. 72.10-45 Section 72.10-45... ARRANGEMENT Means of Escape § 72.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders. Where ladders are...

  6. 46 CFR 174.215 - Drainage of weather deck.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Drainage of weather deck. 174.215 Section 174.215 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES... weather deck. The weather deck must have open rails to allow rapid clearing of water, or must have...

  7. 46 CFR 173.062 - Drainage of weather deck.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each...

  8. 46 CFR 72.10-45 - Weather deck communications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 3 2013-10-01 2013-10-01 false Weather deck communications. 72.10-45 Section 72.10-45... ARRANGEMENT Means of Escape § 72.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders. Where ladders are...

  9. 46 CFR 92.10-45 - Weather deck communications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Weather deck communications. 92.10-45 Section 92.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  10. 46 CFR 92.10-45 - Weather deck communications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Weather deck communications. 92.10-45 Section 92.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  11. 46 CFR 173.062 - Drainage of weather deck.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each...

  12. 46 CFR 190.10-45 - Weather deck communications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Weather deck communications. 190.10-45 Section 190.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  13. 46 CFR 92.10-45 - Weather deck communications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Weather deck communications. 92.10-45 Section 92.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  14. 46 CFR 174.215 - Drainage of weather deck.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Drainage of weather deck. 174.215 Section 174.215 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES... weather deck. The weather deck must have open rails to allow rapid clearing of water, or must have...

  15. 46 CFR 108.167 - Weather deck ladders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Weather deck ladders. 108.167 Section 108.167 Shipping... EQUIPMENT Construction and Arrangement Means of Escape § 108.167 Weather deck ladders. Each unit must have at least one permanent, inclined ladder between each weather deck. Classified Locations...

  16. 46 CFR 174.215 - Drainage of weather deck.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Drainage of weather deck. 174.215 Section 174.215 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES... weather deck. The weather deck must have open rails to allow rapid clearing of water, or must have...

  17. 29 CFR 1918.36 - Weather deck rails.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Weather deck rails. 1918.36 Section 1918.36 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.36 Weather deck rails. Removable weather deck rails shall be kept in place except when cargo operations require them to be...

  18. 46 CFR 108.167 - Weather deck ladders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Weather deck ladders. 108.167 Section 108.167 Shipping... EQUIPMENT Construction and Arrangement Means of Escape § 108.167 Weather deck ladders. Each unit must have at least one permanent, inclined ladder between each weather deck. Classified Locations...

  19. 46 CFR 173.062 - Drainage of weather deck.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each...

  20. 46 CFR 72.10-45 - Weather deck communications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 3 2012-10-01 2012-10-01 false Weather deck communications. 72.10-45 Section 72.10-45... ARRANGEMENT Means of Escape § 72.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders. Where ladders are...

  1. 46 CFR 174.215 - Drainage of weather deck.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Drainage of weather deck. 174.215 Section 174.215 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES... weather deck. The weather deck must have open rails to allow rapid clearing of water, or must have...

  2. 46 CFR 173.062 - Drainage of weather deck.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each...

  3. 46 CFR 190.10-45 - Weather deck communications.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Weather deck communications. 190.10-45 Section 190.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  4. 46 CFR 174.215 - Drainage of weather deck.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Drainage of weather deck. 174.215 Section 174.215 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES... weather deck. The weather deck must have open rails to allow rapid clearing of water, or must have...

  5. 46 CFR 173.062 - Drainage of weather deck.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Drainage of weather deck. 173.062 Section 173.062 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSEL USE School Ships § 173.062 Drainage of weather deck. The weather deck of each...

  6. 46 CFR 108.167 - Weather deck ladders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Weather deck ladders. 108.167 Section 108.167 Shipping... EQUIPMENT Construction and Arrangement Means of Escape § 108.167 Weather deck ladders. Each unit must have at least one permanent, inclined ladder between each weather deck. Classified Locations...

  7. 46 CFR 190.10-45 - Weather deck communications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Weather deck communications. 190.10-45 Section 190.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  8. 29 CFR 1918.36 - Weather deck rails.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Weather deck rails. 1918.36 Section 1918.36 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.36 Weather deck rails. Removable weather deck rails shall be kept in place except when cargo operations require them to be...

  9. 29 CFR 1918.36 - Weather deck rails.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Weather deck rails. 1918.36 Section 1918.36 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.36 Weather deck rails. Removable weather deck rails shall be kept in place except when cargo operations require them to be...

  10. 29 CFR 1918.36 - Weather deck rails.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Weather deck rails. 1918.36 Section 1918.36 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.36 Weather deck rails. Removable weather deck rails shall be kept in place except when cargo operations require them to be...

  11. 29 CFR 1918.36 - Weather deck rails.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Weather deck rails. 1918.36 Section 1918.36 Labor... (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR LONGSHORING Working Surfaces § 1918.36 Weather deck rails. Removable weather deck rails shall be kept in place except when cargo operations require them to be...

  12. 46 CFR 190.10-45 - Weather deck communications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Weather deck communications. 190.10-45 Section 190.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 190.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  13. 46 CFR 92.10-45 - Weather deck communications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Weather deck communications. 92.10-45 Section 92.10-45... CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication shall be provided between the various weather decks by means of permanent inclined ladders....

  14. 46 CFR 12.15-13 - Deck engine mechanic.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Deck engine mechanic. 12.15-13 Section 12.15-13 Shipping... ENDORSEMENTS Qualified Member of the Engine Department § 12.15-13 Deck engine mechanic. (a) An applicant for an endorsement as deck engine mechanic shall be a person holding an MMC or MMD endorsed as junior engineer....

  15. 46 CFR 132.320 - Helicopter-landing decks.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Helicopter-landing decks. 132.320 Section 132.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS FIRE-PROTECTION EQUIPMENT Miscellaneous § 132.320 Helicopter-landing decks. Each vessel with a helicopter-landing deck...

  16. 46 CFR 108.487 - Helicopter deck fueling operations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Helicopter deck fueling operations. 108.487 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.487 Helicopter deck fueling operations. (a) Each helicopter landing deck on which fueling operations...

  17. 46 CFR 108.487 - Helicopter deck fueling operations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Helicopter deck fueling operations. 108.487 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.487 Helicopter deck fueling operations. (a) Each helicopter landing deck on which fueling operations...

  18. 46 CFR 108.487 - Helicopter deck fueling operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Helicopter deck fueling operations. 108.487 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.487 Helicopter deck fueling operations. (a) Each helicopter landing deck on which fueling operations...

  19. 46 CFR 132.320 - Helicopter-landing decks.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Helicopter-landing decks. 132.320 Section 132.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS FIRE-PROTECTION EQUIPMENT Miscellaneous § 132.320 Helicopter-landing decks. Each vessel with a helicopter-landing deck...

  20. 46 CFR 132.320 - Helicopter-landing decks.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Helicopter-landing decks. 132.320 Section 132.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS FIRE-PROTECTION EQUIPMENT Miscellaneous § 132.320 Helicopter-landing decks. Each vessel with a helicopter-landing deck...

  1. 46 CFR 132.320 - Helicopter-landing decks.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Helicopter-landing decks. 132.320 Section 132.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS FIRE-PROTECTION EQUIPMENT Miscellaneous § 132.320 Helicopter-landing decks. Each vessel with a helicopter-landing deck...

  2. 46 CFR 108.487 - Helicopter deck fueling operations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Helicopter deck fueling operations. 108.487 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.487 Helicopter deck fueling operations. (a) Each helicopter landing deck on which fueling operations...

  3. 46 CFR 108.487 - Helicopter deck fueling operations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Helicopter deck fueling operations. 108.487 Section 108... DESIGN AND EQUIPMENT Fire Extinguishing Systems Fire Protection for Helicopter Facilities § 108.487 Helicopter deck fueling operations. (a) Each helicopter landing deck on which fueling operations...

  4. 46 CFR 132.320 - Helicopter-landing decks.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Helicopter-landing decks. 132.320 Section 132.320 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OFFSHORE SUPPLY VESSELS FIRE-PROTECTION EQUIPMENT Miscellaneous § 132.320 Helicopter-landing decks. Each vessel with a helicopter-landing deck...

  5. 46 CFR 42.13-20 - Deck line.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Deck line. 42.13-20 Section 42.13-20 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) LOAD LINES DOMESTIC AND FOREIGN VOYAGES BY SEA General Rules for Determining Load Lines 42.13-20 Deck line. (a) The deck line is a horizontal line...

  6. 46 CFR 111.30-11 - Deck coverings.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 4 2012-10-01 2012-10-01 false Deck coverings. 111.30-11 Section 111.30-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-11 Deck coverings. Non-conducting deck coverings, such as...

  7. 46 CFR 111.30-11 - Deck coverings.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 4 2014-10-01 2014-10-01 false Deck coverings. 111.30-11 Section 111.30-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-11 Deck coverings. Non-conducting deck coverings, such as...

  8. 46 CFR 111.30-11 - Deck coverings.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 4 2013-10-01 2013-10-01 false Deck coverings. 111.30-11 Section 111.30-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-11 Deck coverings. Non-conducting deck coverings, such as...

  9. 46 CFR 111.30-11 - Deck coverings.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Deck coverings. 111.30-11 Section 111.30-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-11 Deck coverings. Non-conducting deck coverings, such as...

  10. 46 CFR 111.30-11 - Deck coverings.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 4 2011-10-01 2011-10-01 false Deck coverings. 111.30-11 Section 111.30-11 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) ELECTRICAL ENGINEERING ELECTRIC SYSTEMS-GENERAL REQUIREMENTS Switchboards § 111.30-11 Deck coverings. Non-conducting deck coverings, such as...

  11. Tire Footprint Affects Hydroplaning On Wet Pavement

    NASA Technical Reports Server (NTRS)

    Yager, Thomas J.

    1989-01-01

    Recent investigations of tire hydroplaning at highway speeds reveal, in addition to inflation pressure, tire-footprint aspect ratio (FAR), defined as width divided by length of tire surface in contact with pavement, significantly influences speed at which dynamic hydroplaning begins. Tire speeds and forces developed during tests of up to 65 mi/h (105 km/h) were monitored on flooded test surface to identify development of hydroplaning. Study focused on automotive tires because FAR's of automotive tires vary more than those of aircraft tires.

  12. Demonstration of dual-band infrared thermal imaging for bridge inspection. Phase II, final report

    SciTech Connect

    Durbin, P.F.; Del Grande, N.K.; Schaich, P.C.

    1996-03-01

    Developing and implementing methods of effective bridge rehabilitation is a major issue for the Federal Highway Administration (FHWA). The nation spends $5 billion annually to replace, rehabilitate or construct new bridges. According to the National Bridge Inventory, over 100,000 U.S. bridges are structurally deficient. About 40,000 of these bridges have advanced deck deterioration. The most common causes of serious deck deterioration is delamination. Delaminations result when steel reinforcements within the bridge deck corrode, creating gaps that separate the concrete into layers. A reliable inspection technology, capable of identifying delaminations, would represent a power new tool in bridge maintenance. To date, most bridge inspections rely on human interpretation of surface visual features of chain dragging. These methods are slow, disruptive, unreliable and raise serious safety concerns. Infrared thermal imaging detects subsurface delaminations and surface clutter, which is introduced by foreign material on the roadway. Typically, foreign material which is not always evident on a video tape image, produces a unique IR reflectance background unlike the thermal response of a subsurface delamination. Lawrence Livermore National Laboratory (LLNL) uses dual-band infrared (DBIR) thermal imaging to identify and remove nonthermal IR reflectance backgrounds from foreign material on the roadway. DBIR methods improve the performance of IR thermal imaging by a factor of ten, compared to single-band infrared (SBIR) methods. DBIR thermal imaging allows precise temperature measurement to reliably locate bridge deck delaminations and remove wavelength-dependent emissivity variations due to foreign material on the roadway.

  13. New structural systems for zero-maintenance pavements. Volume 1: Analytical and experimental studies of an anchored pavement. A candidate zero-maintenance pavement

    NASA Astrophysics Data System (ADS)

    Saxena, S. K.; Rosenkranz, W. J.; Militsopoulos, S. G.

    1980-05-01

    The design feasibility and construction cost effectiveness of an anchored pavement concept for zero maintenance highways are investigated. An analytical model is designed to verify computer program results and to investigate construction methods for a full-scale highway section. A conventional slab and an anchored pavement in both continuous and jointed configurations were subjected to heat transfer, thermal stress, and mechanical stress analyses. The anchored pavement offers two distinct advantages over a conventional pavement. Deflections are lower and more uniform; and stresses in the soil are lower and distributed more widely by the rigid anchors. Three dimensional finite element analysis is considered to be the most efficient technique for examining the significance of environmentally induced stress.

  14. 23 CFR 973.208 - Indian lands pavement management system (PMS).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 23 Highways 1 2010-04-01 2010-04-01 false Indian lands pavement management system (PMS). 973.208... PROGRAM Bureau of Indian Affairs Management Systems § 973.208 Indian lands pavement management system (PMS... concepts described in the AASHTO's “Pavement Management Guide.” 1 1 “Pavement Management Guide,”...

  15. 23 CFR 971.208 - Federal lands pavement management system (PMS).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Federal lands pavement management system (PMS). 971.208... lands pavement management system (PMS). In addition to the requirements provided in § 971.204, the PMS... the concepts described in the AASHTO's “Pavement Management Guide.” 1 1 “Pavement Management...

  16. 23 CFR 973.208 - Indian lands pavement management system (PMS).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 23 Highways 1 2011-04-01 2011-04-01 false Indian lands pavement management system (PMS). 973.208... PROGRAM Bureau of Indian Affairs Management Systems § 973.208 Indian lands pavement management system (PMS... concepts described in the AASHTO's “Pavement Management Guide.” 1 1 “Pavement Management Guide,”...

  17. On Deck with the Scarlett Isabella

    USGS Multimedia Gallery

    A view from the deck of the Scarlett Isabella. The USGS returned from a seafloor data mapping mission offshore of the Delmarva Peninsula (Ocean City, MD) on July 25th, 2014. The data collected is foundational to our continued understanding of coastal change, vulnerabilities, and making our co...

  18. 49 CFR 176.138 - Deck stowage.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Deck stowage. 176.138 Section 176.138 Transportation Other Regulations Relating to Transportation PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION HAZARDOUS MATERIALS REGULATIONS CARRIAGE BY VESSEL...

  19. On Deck with the Scarlett Isabella

    USGS Multimedia Gallery

    A view from the deck of the Scarlett Isabella.  The USGS returned from a seafloor data mapping mission offshore of the Delmarva Peninsula (Ocean City, MD) on July 25th, 2014. The data collected is foundational to our continued understanding of coastal change, vulnerabilities, and making our co...

  20. 46 CFR 177.900 - Deck rails.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... strength and support equivalent to fixed rails. Deck rails must include a top rail with the minimum height..., dinner and party cruises, and overnight cruises, must be at least 1,000 millimeters (39.5 inches) high...,000 millimeters (39.5 inches) high. (3) All other rails must be at least 910 millimeters (36...

  1. Flight deck automation: Promises and realities

    NASA Technical Reports Server (NTRS)

    Norman, Susan D. (Editor); Orlady, Harry W. (Editor)

    1989-01-01

    Issues of flight deck automation are multifaceted and complex. The rapid introduction of advanced computer-based technology onto the flight deck of transport category aircraft has had considerable impact both on aircraft operations and on the flight crew. As part of NASA's responsibility to facilitate an active exchange of ideas and information among members of the aviation community, a NASA/FAA/Industry workshop devoted to flight deck automation, organized by the Aerospace Human Factors Research Division of NASA Ames Research Center. Participants were invited from industry and from government organizations responsible for design, certification, operation, and accident investigation of transport category, automated aircraft. The goal of the workshop was to clarify the implications of automation, both positive and negative. Workshop panels and working groups identified issues regarding the design, training, and procedural aspects of flight deck automation, as well as the crew's ability to interact and perform effectively with the new technology. The proceedings include the invited papers and the panel and working group reports, as well as the summary and conclusions of the conference.

  2. TDWR information on the flight deck

    NASA Technical Reports Server (NTRS)

    Hinton, Dave

    1991-01-01

    TDWR information on the flight deck is presented in the form of view-graphs. The following subject areas are covered: air/ground wind shear information integration research; wind shear detection/warning and avoidance system; initial experiment; and future plans.

  3. 46 CFR 116.900 - Deck rails.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... direction. The point and uniform loads do not need to be applied simultaneously. (c) Where space limitations... International Convention on Load Lines must be at least 1,000 millimeters (39.5 inches) high. (3) All other... required by paragraph (a) of this section and the deck so that no open space exists that is more than...

  4. 46 CFR 116.900 - Deck rails.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... direction. The point and uniform loads do not need to be applied simultaneously. (c) Where space limitations... International Convention on Load Lines must be at least 1,000 millimeters (39.5 inches) high. (3) All other... required by paragraph (a) of this section and the deck so that no open space exists that is more than...

  5. 46 CFR 116.900 - Deck rails.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... direction. The point and uniform loads do not need to be applied simultaneously. (c) Where space limitations... International Convention on Load Lines must be at least 1,000 millimeters (39.5 inches) high. (3) All other... required by paragraph (a) of this section and the deck so that no open space exists that is more than...

  6. 46 CFR 116.900 - Deck rails.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... direction. The point and uniform loads do not need to be applied simultaneously. (c) Where space limitations... International Convention on Load Lines must be at least 1,000 millimeters (39.5 inches) high. (3) All other... required by paragraph (a) of this section and the deck so that no open space exists that is more than...

  7. 46 CFR 116.900 - Deck rails.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... direction. The point and uniform loads do not need to be applied simultaneously. (c) Where space limitations... International Convention on Load Lines must be at least 1,000 millimeters (39.5 inches) high. (3) All other... required by paragraph (a) of this section and the deck so that no open space exists that is more than...

  8. Flight-deck automation: Promises and problems

    NASA Technical Reports Server (NTRS)

    Wiener, E. L.; Curry, R. E.

    1980-01-01

    The state of the art in human factors in flight-deck automation is presented. A number of critical problem areas are identified and broad design guidelines are offered. Automation-related aircraft accidents and incidents are discussed as examples of human factors problems in automated flight.

  9. Commander Lousma sleeps on aft flight deck

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Commander Lousma, tethered to panel A12, sleeps on aft flight deck starboard side. Pilots ejection seat (S2) seat back with portable oxygen system (POS) assemby, Onorbit Station control panels, and Mission Station control panels surround Lousma. Window shade is in place in overhead window W7 just above his feet.

  10. Utilization of Advanced Diagnostic Methods for Texture and Rut Depth Analysis on a Testing Pavement Section

    NASA Astrophysics Data System (ADS)

    Slabej, Martin; Grinč, Michal; Kotek, Peter; Kováč, Matúš; Decký, Martin

    2015-05-01

    Qualitative characteristics of pavement in wide range reflects the pavement serviceability, which is a summary of the characteristics of the pavement, providing a fast, smooth, economical and especially safe driving of motor-vehicles. The target factor of pavement serviceability and safety of roads represents the quality of their surface properties. In the framework of research activities performed in the Research Centre founded under the auspices of University of Žilina, individual parameters of pavement serviceability were monitored by pavement surface scanning. This paper describes the creation of a 3D - road surface model and its analysis and evaluation from the viewpoint of two pavement serviceability parameters - the rut depth and texture. Measurements were performed on an experimental pavement section used contemporary in an Accelerated Pavement Testing experiment. The long-term goal is to ascertain functions predicting degradation of these two pavement serviceability parameters.

  11. Evaluation of flexible pavement performance life in Florida. Final research report, October 1993--June 1998

    SciTech Connect

    Ping, W.V.; He, Y.

    1998-06-01

    The pavement performance life provides information on how long a particular pavement type will typically last before it needs rehabilitation. This study presents the research effort to estimate the average flexible pavement performance life in Florida. Two data files of Pavement Condition Survey (PCS) and Work Program Administration (WPA) were used for this study. SAS programs were applied to analyze and manipulate these two data files. The pavement performance condition curves were developed for a large sample size of pavement sections based on the polynomial model. The average pavement performance lives were evaluated for each pavement group based on the performance curves. The results of the evaluation showed that the primary system had longer average performance life than the interstate system. Generally, the polynomial model performed well in fitting the data. The pavement performance curve indicates that if M and R are performed while the pavement is still in the `slow rate of deterioration` phase, life cycle cost may be reduced.

  12. Cognitive representations of flight-deck information attributes

    NASA Technical Reports Server (NTRS)

    Ricks, Wendell R.; Jonsson, Jon E.; Rogers, William H.

    1994-01-01

    A large number of aviation issues are generically being called fligh-deck information management issues, underscoring the need for an organization or classification structure. One objective of this study was to empirically determine how pilots organize flight-deck information attributes and -- based upon that data -- develop a useful taxonomy (in terms of better understanding the problems and directing solutions) for classifying flight-deck information management issues. This study also empirically determined how pilots model the importance of flight-deck information attributes for managing information. The results of this analysis suggest areas in which flight-deck researchers and designers may wish to consider focusing their efforts.

  13. Evaluation of base widening methods on flexible pavements in Wyoming

    NASA Astrophysics Data System (ADS)

    Offei, Edward

    The surface transportation system forms the biggest infrastructure investment in the United States of which the roadway pavement is an integral part. Maintaining the roadways can involve rehabilitation in the form of widening, which requires a longitudinal joint between the existing and new pavement sections to accommodate wider travel lanes, additional travel lanes or modification to shoulder widths. Several methods are utilized for the joint construction between the existing and new pavement sections including vertical, tapered and stepped joints. The objective of this research is to develop a formal recommendation for the preferred joint construction method that provides the best base layer support for the state of Wyoming. Field collection of Dynamic Cone Penetrometer (DCP) data, Falling Weight Deflectometer (FWD) data, base samples for gradation and moisture content were conducted on 28 existing and 4 newly constructed pavement widening projects. A survey of constructability issues on widening projects as experienced by WYDOT engineers was undertaken. Costs of each joint type were compared as well. Results of the analyses indicate that the tapered joint type showed relatively better pavement strength compared to the vertical joint type and could be the preferred joint construction method. The tapered joint type also showed significant base material savings than the vertical joint type. The vertical joint has an 18% increase in cost compared to the tapered joint. This research is intended to provide information and/or recommendation to state policy makers as to which of the base widening joint techniques (vertical, tapered, stepped) for flexible pavement provides better pavement performance.

  14. Noise from Aft Deck Exhaust Nozzles: Differences in Experimental Embodiments

    NASA Technical Reports Server (NTRS)

    Bridges, James

    2014-01-01

    Two embodiments of a rectangular nozzle on an aft deck are compared. In one embodiment the lower lip of the nozzle was extended with the sidewalls becoming triangles. In a second embodiment a rectangular nozzle was fitted with a surface that fit flush to the lower lip and extended outward from the sides of the nozzle, approximating a semi-infinite plane. For the purpose of scale-model testing, making the aft deck an integral part of the nozzle is possible for relatively short deck lengths, but a separate plate model is more flexible, accounts for the expanse of deck to the sides of the nozzle, and allows the nozzle to stand off from the deck. Both embodiments were tested and acoustic far-field results were compared. In both embodiments the extended deck introduces a new noise source, but the amplitude of the new source was dependent upon the span (cross-stream dimension) of the aft deck. The noise increased with deck length (streamwise dimension), and in the case of the beveled nozzle it increased with increasing aspect ratio. In previous studies of slot jets in wings it was noted that the increased noise from the extended aft deck appears as a dipole at the aft deck trailing edge, an acoustic source type with different dependence on velocity than jet mixing noise. The extraneous noise produced by the aft deck in the present studies also shows this behavior both in directivity and in velocity scaling.

  15. The Collapse of the I-35W Bridge in Minneapolis

    ERIC Educational Resources Information Center

    Feldman, Bernard J.

    2010-01-01

    On Wednesday, Aug. 1, 2007, at 6:05 p.m. (during evening rush hour), the I-35W bridge across the Mississippi River in Minneapolis collapsed, killing 13 people and injuring 145. At the time of the collapse, repair work was in progress on the deck of the bridge, resulting in an additional 287 tons of construction material and equipment being on the

  16. The Collapse of the I-35W Bridge in Minneapolis

    ERIC Educational Resources Information Center

    Feldman, Bernard J.

    2010-01-01

    On Wednesday, Aug. 1, 2007, at 6:05 p.m. (during evening rush hour), the I-35W bridge across the Mississippi River in Minneapolis collapsed, killing 13 people and injuring 145. At the time of the collapse, repair work was in progress on the deck of the bridge, resulting in an additional 287 tons of construction material and equipment being on the…

  17. 57. INTERIOR VIEW OF VAL BRIDGE STRUCTURE SHOWING LAUNCHING TUBE, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    57. INTERIOR VIEW OF VAL BRIDGE STRUCTURE SHOWING LAUNCHING TUBE, STAIRS AND PORTION OF LAUNCHING DECK. NOTE SUPPORT CARRIAGE ASSEMBLY IN DISTANCE. Date unknown, circa March 1948. (Original photograph in possession of Dave Willis, San Diego, California.) - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  18. Detail of the substructure of the bridge showing the interior ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of the substructure of the bridge showing the interior of the open spandrel, facing northeast. Note how the decking rests upon the spandrel columns. - Oakland Avenue Viaduct, Oakland Avenue spanning U.S. Route 62 (State Route 2302) & Pine Run, Sharon, Mercer County, PA

  19. 86. Round Meadow Creek Viaduct. This steel girder bridge, built ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    86. Round Meadow Creek Viaduct. This steel girder bridge, built in 1939, has a reinforced concrete deck and piers. It is an example of a major in-line, or straight, viaduct over a deep ravine. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  20. Organic Functional Group Playing Card Deck

    NASA Astrophysics Data System (ADS)

    Welsh, Michael J.

    2003-04-01

    The recognition and identification of organic functional groups, while essential for chemistry and biology majors, is also very useful for non-science majors in the study of molecules in art and life. In order to make this task more palatable for the non-science major (art and communications students), the images of a traditional playing deck of cards (heart, spade, diamond, and club) have been replaced with four representations of common organic functional groups. The hierarchy rules for naming two groups in a molecule is loosely incorporated to represent the sequence (King, Queen, Jack, ?, Ace) of the deck. Students practice recognizing and identifying organic groups by playing simple card games of "Old Maid" and "Go Fish". To play games like "Poker" or "Gin", a student must not only recognize the functional groups, but also master a naming hierarchy for the organic groups.

  1. Recycling of water-susceptible pavements

    NASA Astrophysics Data System (ADS)

    Maupin, G. W.

    1980-05-01

    Several bituminous concrete interstate pavements that experienced failures suspected to have been caused by stripping were investigated. On two projects, the degree of deterioration, potential serviceability, and possible remedial measures were studied. Cores were taken to determine the degreee of stripping and tensile strength, and dynaflect tests were performed. An emulsion mix design was developed for stripped bituminous concrete removed from another project with the expectation that it could be used as a surface mix on a highway with a low traffic volume. While this expectation was not realized, it was concluded that the material is suitable for use in a base mix. A maintenance resurfacing on a fourth project that experienced stripping failure is being monitored and the performance is being evaluated.

  2. Training needs for advanced technology flight decks.

    PubMed

    Maurino, D

    1991-05-01

    The author examines training implications of increased automation in aircraft flight decks. Training issues include the need for basic pilot skills and knowledge, general knowledge of the aircraft, revision of Cockpit Resource Management (CRM) to reflect changes due to technology, and tailoring Line-Oriented Flight Training to focus on routine human-automation interfaces and CRM principles in addition to scenarios of abnormal conditions. PMID:11539339

  3. ANALYSIS OF GROUP MAINTENANCE STRATEGY -ROAD PAVEMENT AND SEWERAGE PIPES-

    NASA Astrophysics Data System (ADS)

    Tanimoto, Keishi; Sugimoto, Yasuaki; Miyamoto, Shinya; Nada, Hideki; Hosoi, Yoshihiko

    Recently, it is critical to manage deteriorating sewerage and road facilities efficiently and strategically. Since the sewerage pipes are mostly installed under road pavement, the works for the replacement of the sewerage pipes are partially common to the works for the road. This means that the replacement cost can be saved by coordinating the timing of the replacements by sewerage pipe and road pavement. The purpose of the study is to develop the model based on Markov decision process to derive the optimal group maintenance policy so as to minimize lifecycle cost. Then the model is applied to case study area and demonstrated to estimate the lifecycle cost using statistical data such as pipe replacement cost, road pavement rehabilitation cost, and state of deterioration of pipes and road pavement.

  4. Asphalt pavement surfaces and asphalt mixtures. Transportation research record

    SciTech Connect

    1996-12-31

    The papers in this volume, which deal with asphalt pavement surfaces and asphalt mixtures, should be of interest to state and local construction, design, materials, and research engineers as well as contractors and material producers. The papers in Part 1 include discussions of pavement smoothness specifications and skidding characteristics. The first four papers in Part 2 were submitted in response to a call for papers for a session at the 75th Annual Meeting of the Transportation Research Board on low-temperature properties of hot-mix asphalt. The next eight are on the influence of volumetric and strength properties on the performance of hot-mix asphalt. In the following three papers, the topics covered are the complex modulus of asphalt concrete, cold in-place asphalt recycling, and polymer modification of asphalt pavements in Ontario. The last two papers were presented in a session on relationship of materials characterization to accelerated pavement performance testing.

  5. Striated clast pavements: Products of deforming subglacial sediment?

    NASA Astrophysics Data System (ADS)

    Clark, Peter U.

    1991-05-01

    Studies of modern glaciers have recently drawn attention to the importance of subglacial sediment deformation to glacier dynamics and processes. Inferences regarding the probable shear strength of this sediment imply that large clasts may in some cases sink to underlying rigid sediment, where abrasion by overlying deforming sediment could occur. This scenario provides a formative mechanism for striated clast pavements commonly described from the base of fine-grained massive diamictons associated with the late Pleistocene Laurentide ice sheet. Such a mechanism indicates that, at the time of formation of clast pavements, overlying diamictons associated with pavements had a low yield strength (?0.5 kPa) and were deforming mechanically like a debris flow. Clast pavements may therefore be an important criterion for recognition of sediments deposited by subglacial deformation transport.

  6. Nondestructive evaluation of load transfer at rigid airport pavement joints

    NASA Astrophysics Data System (ADS)

    Hammons, Michael I.

    1995-07-01

    Current design criteria for rigid pavements for commercial and military airfields assume that 25% of the load applied to an edge of a slab is transferred through the joint to an adjacent unloaded slab. A nondestructive testing technique using a falling weight deflectometer (FWD) was used to conduct field testing at a number of sites. A transfer function, developed from an analytical study, was used to estimate load transfer from the measured joint efficiency as a function of the loaded area and the radius of relative stiffness of the pavement. This procedure, although analytically sound, lacks actual field verification at an instrumented pavement site. This procedure was used to estimate load transfer at a number of commercial and military airfields for a variety of joint types, climate conditions, and pavement structures. The results of these tests indicate that the assumption of load transfer as a constant value of 25% appears to be unconservative, especially during the winter months.

  7. Development of probabilistic rigid pavement design methodologies for military airfields

    NASA Astrophysics Data System (ADS)

    Witczak, M. W.; Uzan, J.; Johnson, M.

    1983-12-01

    The current Corps of Engineers design procedures for rigid airfield pavements is based on the Westergaard free edge stress slab theory, and a proposed procedure is based on the multilayer elastic theory. These two design procedures have been expanded to airfield pavement designs expressed in probabilistic and reliability terms. Further developments were required in these procedures to make the analysis more practicable. Two major investigations were conducted: (1) Evaluation and use of the composite modulus of elasticity for layers beneath the rigid pavement, and (2) Evaluation of the maximum tensile stress at the bottom of the slab for different aircraft types. Derivations obtained from the investigation of the composite modulus and maximum tensile stress are reported and are included in computer programs for probabilistic/reliability analysis of rigid pavements. The approximate closed form (Taylor series expansion) is utilized. Example runs of the computer program are presented.

  8. Permeable Pavement Demonstration at the Edison Environmental Center - Poster

    EPA Science Inventory

    Poster for the SAB Review detailing the porous pavement parking lot project. The poster describes the design of the parking lot, the research components that were incorporated into the design, and the monitoring plan.

  9. Cloud Impacts on Pavement Temperature in Energy Balance Models

    NASA Astrophysics Data System (ADS)

    Walker, C. L.

    2013-12-01

    Forecast systems provide decision support for end-users ranging from the solar energy industry to municipalities concerned with road safety. Pavement temperature is an important variable when considering vehicle response to various weather conditions. A complex, yet direct relationship exists between tire and pavement temperatures. Literature has shown that as tire temperature increases, friction decreases which affects vehicle performance. Many forecast systems suffer from inaccurate radiation forecasts resulting in part from the inability to model different types of clouds and their influence on radiation. This research focused on forecast improvement by determining how cloud type impacts the amount of shortwave radiation reaching the surface and subsequent pavement temperatures. The study region was the Great Plains where surface solar radiation data were obtained from the High Plains Regional Climate Center's Automated Weather Data Network stations. Road pavement temperature data were obtained from the Meteorological Assimilation Data Ingest System. Cloud properties and radiative transfer quantities were obtained from the Clouds and Earth's Radiant Energy System mission via Aqua and Terra Moderate Resolution Imaging Spectroradiometer satellite products. An additional cloud data set was incorporated from the Naval Research Laboratory Cloud Classification algorithm. Statistical analyses using a modified nearest neighbor approach were first performed relating shortwave radiation variability with road pavement temperature fluctuations. Then statistical associations were determined between the shortwave radiation and cloud property data sets. Preliminary results suggest that substantial pavement forecasting improvement is possible with the inclusion of cloud-specific information. Future model sensitivity testing seeks to quantify the magnitude of forecast improvement.

  10. Urban pavement surface temperature. Comparison of numerical and statistical approach

    NASA Astrophysics Data System (ADS)

    Marchetti, Mario; Khalifa, Abderrahmen; Bues, Michel; Bouilloud, Ludovic; Martin, Eric; Chancibaut, Katia

    2015-04-01

    The forecast of pavement surface temperature is very specific in the context of urban winter maintenance. to manage snow plowing and salting of roads. Such forecast mainly relies on numerical models based on a description of the energy balance between the atmosphere, the buildings and the pavement, with a canyon configuration. Nevertheless, there is a specific need in the physical description and the numerical implementation of the traffic in the energy flux balance. This traffic was originally considered as a constant. Many changes were performed in a numerical model to describe as accurately as possible the traffic effects on this urban energy balance, such as tires friction, pavement-air exchange coefficient, and infrared flux neat balance. Some experiments based on infrared thermography and radiometry were then conducted to quantify the effect fo traffic on urban pavement surface. Based on meteorological data, corresponding pavement temperature forecast were calculated and were compared with fiels measurements. Results indicated a good agreement between the forecast from the numerical model based on this energy balance approach. A complementary forecast approach based on principal component analysis (PCA) and partial least-square regression (PLS) was also developed, with data from thermal mapping usng infrared radiometry. The forecast of pavement surface temperature with air temperature was obtained in the specific case of urban configurtation, and considering traffic into measurements used for the statistical analysis. A comparison between results from the numerical model based on energy balance, and PCA/PLS was then conducted, indicating the advantages and limits of each approach.

  11. Pore-structure models of hydraulic conductivity for permeable pavement

    NASA Astrophysics Data System (ADS)

    Kuang, X.; Sansalone, J.; Ying, G.; Ranieri, V.

    2011-03-01

    SummaryPermeable pavement functions as a porous infrastructure interface allowing the infiltration and evaporation of rainfall-runoff while functioning as a relatively smooth load-bearing surface for vehicular transport. Hydraulic conductivity ( k) of permeable pavement is an important hydraulic property and is a function of the pore structure. This study examines k for a cementitious permeable pavement (CPP) through a series of pore-structure models. Measurements utilized include hydraulic head as well as total porosity, ( ? t), effective porosity ( ? e), tortuosity ( L e/ L) and pore size distribution (PSD) indices generated through X-ray tomography (XRT). XRT results indicate that the permeable pavement pore matrix is hetero-disperse, with high tortuosity and ? t ? ? e. Power law models of k- ? t and k- ? e relationships are developed for a CPP mix design. Results indicate that the Krger, Fair-Hatch, Hazen, Slichter, Beyer and Terzaghi models based on simple pore-structure indices do not reproduce measured k values. The conventional Kozeny-Carman model (KCM), a more parameterized pore-structure model, did not reproduce measured k values. This study proposes a modified KCM utilizing ? e, specific surface area (SSA) pe and weighted tortuosity ( L e/ L) w. Results demonstrate that such permeable pavement pore-structure parameters with the modified KCM can predict k. The k results are combined with continuous simulation modeling using historical rainfall to provide nomographs examining permeable pavement as a low impact development (LID) infrastructure component.

  12. Bridge permeameter

    DOEpatents

    Graf, D.C.; Warpinski, N.R.

    1996-08-13

    A system is described for single-phase, steady-state permeability measurements of porous rock which utilizes a fluid bridge arrangement analogous to a Wheatstone bridge. The arms of the bridge contain the sample and calibrated flow resistors. 8 figs.

  13. Recycled materials in asphalt pavements. (Latest citations from the NTIS bibliographic database). Published Search

    SciTech Connect

    Not Available

    1994-05-01

    The bibliography contains citations concerning the recycling of asphalt pavement materials, and the use of other recycled materials to manufacture asphalt pavement. Articles discuss methods used for recycling bituminous pavement including hot-mix and cold-mix. Materials used to improve recycled pavement, and recycled materials used in asphalt pavement include latexes, rubber scrap such as tires, glass shards, concretes, dusts, waste oils, roofing wastes, sulfur, and metal refining sludges. Testing and evaluation of recycled pavements both in laboratories and in test cases are considered. (Contains a minimum of 160 citations and includes a subject term index and title list.)

  14. 46 CFR 28.565 - Water on deck.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 1 2012-10-01 2012-10-01 false Water on deck. 28.565 Section 28.565 Shipping COAST... VESSELS Stability § 28.565 Water on deck. (a) Each vessel with bulwarks must comply with the requirements... energy, “b” in Figure 28.565, must not be less than the water on deck heeling energy, “a” in Figure...

  15. 46 CFR 28.565 - Water on deck.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 1 2013-10-01 2013-10-01 false Water on deck. 28.565 Section 28.565 Shipping COAST... VESSELS Stability § 28.565 Water on deck. (a) Each vessel with bulwarks must comply with the requirements... energy, “b” in Figure 28.565, must not be less than the water on deck heeling energy, “a” in Figure...

  16. 46 CFR 28.565 - Water on deck.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Water on deck. 28.565 Section 28.565 Shipping COAST... VESSELS Stability § 28.565 Water on deck. (a) Each vessel with bulwarks must comply with the requirements... energy, “b” in Figure 28.565, must not be less than the water on deck heeling energy, “a” in Figure...

  17. 46 CFR 28.565 - Water on deck.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 1 2014-10-01 2014-10-01 false Water on deck. 28.565 Section 28.565 Shipping COAST... VESSELS Stability § 28.565 Water on deck. (a) Each vessel with bulwarks must comply with the requirements... energy, “b” in Figure 28.565, must not be less than the water on deck heeling energy, “a” in Figure...

  18. 46 CFR 28.565 - Water on deck.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 1 2011-10-01 2011-10-01 false Water on deck. 28.565 Section 28.565 Shipping COAST... VESSELS Stability § 28.565 Water on deck. (a) Each vessel with bulwarks must comply with the requirements... energy, “b” in Figure 28.565, must not be less than the water on deck heeling energy, “a” in Figure...

  19. 46 CFR 11.403 - Structure of deck officer endorsements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... officer endorsements. The following diagram illustrates the deck officer endorsement structure, including cross over points. The section numbers on the diagram refer to the specific requirements...

  20. 26. RAILROAD, RR BRIDGE MISSISSIPPI, CLAY CO., WAVERLY 1.5 mi. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    26. RAILROAD, RR BRIDGE MISSISSIPPI, CLAY CO., WAVERLY 1.5 mi. S of MS. 50 Proposed 218-foot deck, plate-girder turn span, submitted by the Wisconsin Bridge and Iron Co., Milwaukee, Wisc. May 15 1914. Act size: approx. 23x34 in. Credit: columbus and Greenville RR, Columbus, Ms. Sarcone Photography, Columbus, Ms. Sep 1978. - Bridges of the Upper Tombigbee River Valley, Columbus, Lowndes County, MS

  1. Modeling and analysis of the in-plane vibration of a complex cable-stayed bridge

    NASA Astrophysics Data System (ADS)

    Cao, D. Q.; Song, M. T.; Zhu, W. D.; Tucker, R. W.; Wang, C. H.-T.

    2012-12-01

    The in-plane vibration of a complex cable-stayed bridge that consists of a simply-supported four-cable-stayed deck beam and two rigid towers is studied. The nonlinear and linear partial differential equations that govern transverse and longitudinal vibrations of the cables and transverse vibrations of segments of the deck beam, respectively, are derived, along with their boundary and matching conditions. The undamped natural frequencies and mode shapes of the linearized model of the cable-stayed bridge are determined, and orthogonality relations of the mode shapes are established. Numerical analysis of the natural frequencies and mode shapes of the cable-stayed bridge is conducted for various symmetrical and non-symmetrical bridge cases with regards to the sizes of the components of the bridge and the initial sags of the cables. The results show that there are very close natural frequencies when the bridge model is symmetrical and/or partially symmetrical, and the mode shapes tend to be more localized when the bridge model is less symmetrical. The relationships between the natural frequencies and mode shapes of the cable-stayed bridge and those of a single fixed-fixed cable and the single simply-supported deck beam are analyzed. The results, which are validated by commercial finite element software, demonstrate some complex classical resonance behavior of the cable-stayed bridge.

  2. 46 CFR 28.810 - Deck rails, lifelines, storm rails and hand grabs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels 28.810 Deck rails, lifelines... installed deck rails will impede normal cargo operations or emergency recovery operations. (e) Deck rails...

  3. 46 CFR 28.810 - Deck rails, lifelines, storm rails and hand grabs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels 28.810 Deck rails, lifelines... installed deck rails will impede normal cargo operations or emergency recovery operations. (e) Deck rails...

  4. 46 CFR 28.810 - Deck rails, lifelines, storm rails and hand grabs.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels 28.810 Deck rails, lifelines... installed deck rails will impede normal cargo operations or emergency recovery operations. (e) Deck rails...

  5. 46 CFR 28.810 - Deck rails, lifelines, storm rails and hand grabs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels 28.810 Deck rails, lifelines... installed deck rails will impede normal cargo operations or emergency recovery operations. (e) Deck rails...

  6. 46 CFR 28.810 - Deck rails, lifelines, storm rails and hand grabs.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... REQUIREMENTS FOR COMMERCIAL FISHING INDUSTRY VESSELS Aleutian Trade Act Vessels 28.810 Deck rails, lifelines... installed deck rails will impede normal cargo operations or emergency recovery operations. (e) Deck rails...

  7. Golden Gate Bridge response: a study with low-amplitude data from three earthquakes

    USGS Publications Warehouse

    Celebi, Mehmet

    2012-01-01

    The dynamic response of the Golden Gate Bridge, located north of San Francisco, CA, has been studied previously using ambient vibration data and finite element models. Since permanent seismic instrumentation was installed in 1993, only small earthquakes that originated at distances varying between ~11 to 122 km have been recorded. Nonetheless, these records prompted this study of the response of the bridge to low amplitude shaking caused by three earthquakes. Compared to previous ambient vibration studies, the earthquake response data reveal a slightly higher fundamental frequency (shorter-period) for vertical vibration of the bridge deck center span (~7.78.3 s versus 8.210.6 s), and a much higher fundamental frequency (shorter period) for the transverse direction of the deck (~11.2416.3 s versus ~18.2 s). In this study, it is also shown that these two periods are dominant apparent periods representing interaction between tower, cable, and deck.

  8. POROUS PAVEMENT PHASE I DESIGN AND OPERATIONAL CRITERIA (EPA/600/2-80/135)

    EPA Science Inventory

    Design and operational criteria, utilization concepts, benefits and disadvantages, as well as other characteristics of porous pavements are presented in this report. Particular emphasis is placed on porous asphalt pavements, but the criteria and design approach are applicable to ...

  9. Evaluation of Three Porous Pavement Systems in a Newly Constructed Parking Lot

    EPA Science Inventory

    This project examines porous pavement systems in a newly constructed parking lot next to Building 205 at the Edison Environmental Center. Porous pavement systems are one means of promoting environmental sustainability through stormwater runoff reduction. This project examines t...

  10. Stormwater quality of spring-summer-fall effluent from three partial-infiltration permeable pavement systems and conventional asphalt pavement.

    PubMed

    Drake, Jennifer; Bradford, Andrea; Van Seters, Tim

    2014-06-15

    This study examined the spring, summer and fall water quality performance of three partial-infiltration permeable pavement (PP) systems and a conventional asphalt pavement in Ontario. The study, conducted between 2010 and 2012, compared the water quality of effluent from two Interlocking Permeable Concrete Pavements (AquaPave(®) and Eco-Optiloc(®)) and a Hydromedia(®) Pervious Concrete pavement with runoff from an Asphalt control pavement. The usage of permeable pavements can mitigate the impact of urbanization on receiving surface water systems through quantity control and stormwater treatment. The PP systems provided excellent stormwater treatment for petroleum hydrocarbons, total suspended solids, metals (copper, iron, manganese and zinc) and nutrients (total-nitrogen and total-phosphorus) by reducing event mean concentrations (EMC) as well as total pollutant loadings. The PPs significantly reduced the concentration and loading of ammonia (NH4(+)+NH3), nitrite (NO2(-)) and organic-nitrogen (Org-N) but increased the concentration and loading of nitrate (NO3(-)). The PP systems had mixed performances for the treatment of phosphate (PO4(3-)). The PP systems increased the concentration of sodium (Na) and chloride (Cl) but EMCs remained well below recommended levels for drinking water quality. Relative to the observed runoff, winter road salt was released more slowly from the PP systems resulting in elevated spring and early-summer Cl and Na concentrations in effluent. PP materials were found to introduce dissolved solids into the infiltrating stormwater. The release of these pollutants was verified by additional laboratory scale testing of the individual pavement and aggregate materials at the University of Guelph. Pollutant concentrations were greatest during the first few months after construction and declined rapidly over the course of the study. PMID:24681366

  11. Investigation of factors affecting asphalt pavement recycling and asphalt compatibility

    SciTech Connect

    Venable, R.L.; Petersen, J.C.; Robertson, R.E.; Plancher, H.

    1983-03-01

    Both economic and environmental factors dictate that asphalt pavement be recycled. Many recycling projects have been completed using a variety of recycling additives, but little work has been done on the physiochemical aspects of pavement recycling. The present exploratory study was undertaken to better define the physiochemical variables of recycling. Objectives of the present study include: (1) to determine if molecular structuring in the asphalt binder could be observed in oxidized (air-aged) asphalt-aggregate briquets, and if so, how was structuring affected during briquits, and if so, how was structuring affected during briquet recycling and (2) to determine if recycling agents penetrate the strongly adsorbed asphalt layer on the aggregate surface. Differences were seen in asphalt component compatibility as judged by the state of peptization parameters. In extreme cases the values of the parameters correlated with properties of asphalts of known compatibility; however, a relationship between the parameters determined on a series of asphalts in pavements was not established. The parameters might be useful in evaluating additives for pavement recycling; however, more systems need to be studied to fully assess their potential usefulness. Finally, the parameters need to be correlated with performance-related measurements such as asphalt rheological and mix properties. Examination of the parameters and their changes on asphalt oxidative aging may also be informative with regard to asphalt durability inasmuch as oxidation-induced changes are a major cause of asphalt pavement failure.

  12. Experimental study of a highway bridge with shape memory alloy restrainers focusing on the mitigation of unseating and pounding

    NASA Astrophysics Data System (ADS)

    Guo, Anxin; Zhao, Qingjie; Li, Hui

    2012-03-01

    This paper presents an experimental study to investigate the performance of shape memory alloy (SMA) restrainers for mitigating the pounding and unseating of highway bridges when subjected to seismic excitations. Mechanical property tests of the SMA wire used in the restrainers are conducted first to understand the pseudo-elastic characteristics of the material. Then, a series of shaking table tests are carried out on a highway bridge model. The structural responses of the highway bridge model equipped with SMA restrainers, installed in the form of deck-deck and deck-pile connections, are analyzed and compared with the uncontrolled structures. The test results of this study indicate that the SMA restrainers are not only effective in preventing unseating but also in suppressing the seismic-induced pounding of the highway bridge model used in this study.

  13. 49 CFR 1544.237 - Flight deck privileges.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., under 14 CFR parts 121, 125, or 135. This section does not restrict access for a Federal Air Marshal... 49 Transportation 9 2013-10-01 2013-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door...

  14. 49 CFR 1544.237 - Flight deck privileges.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., under 14 CFR parts 121, 125, or 135. This section does not restrict access for a Federal Air Marshal... 49 Transportation 9 2012-10-01 2012-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door...

  15. 49 CFR 1544.237 - Flight deck privileges.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., under 14 CFR parts 121, 125, or 135. This section does not restrict access for a Federal Air Marshal... 49 Transportation 9 2014-10-01 2014-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door...

  16. 49 CFR 1544.237 - Flight deck privileges.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., under 14 CFR parts 121, 125, or 135. This section does not restrict access for a Federal Air Marshal... 49 Transportation 9 2010-10-01 2010-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door...

  17. 49 CFR 1544.237 - Flight deck privileges.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., under 14 CFR parts 121, 125, or 135. This section does not restrict access for a Federal Air Marshal... 49 Transportation 9 2011-10-01 2011-10-01 false Flight deck privileges. 1544.237 Section 1544.237... COMMERCIAL OPERATORS Operations § 1544.237 Flight deck privileges. (a) For each aircraft that has a door...

  18. 29 CFR 1915.165 - Ship's deck machinery.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 29 Labor 7 2014-07-01 2014-07-01 false Ship's deck machinery. 1915.165 Section 1915.165 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems 1915.165 Ship's deck machinery. (a) Before work is performed on the anchor windlass or any...

  19. 29 CFR 1915.165 - Ship's deck machinery.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 29 Labor 7 2012-07-01 2012-07-01 false Ship's deck machinery. 1915.165 Section 1915.165 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems 1915.165 Ship's deck machinery. (a) Before work is performed on the anchor windlass or any...

  20. 29 CFR 1915.165 - Ship's deck machinery.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 29 Labor 7 2013-07-01 2013-07-01 false Ship's deck machinery. 1915.165 Section 1915.165 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems 1915.165 Ship's deck machinery. (a) Before work is performed on the anchor windlass or any...

  1. 29 CFR 1915.165 - Ship's deck machinery.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 29 Labor 7 2011-07-01 2011-07-01 false Ship's deck machinery. 1915.165 Section 1915.165 Labor... (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems 1915.165 Ship's deck machinery. (a) Before work is performed on the anchor windlass or any...

  2. Crewmember working on the mid deck Zeolite Crystal Growth experiment.

    NASA Technical Reports Server (NTRS)

    1992-01-01

    View showing Payload Specialist Bonnie Dunbar, in the mid deck, conducting the Zeolite Crystal Growth (ZCG) Experiment in the mid deck stowage locker work area. View shows assembly of zeolite sample in the metal autoclave cylinders prior to insertion into the furnace.

  3. 27. VIEW LOOKING AFT ON STARBOARD SIDE OF MAIN DECK ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    27. VIEW LOOKING AFT ON STARBOARD SIDE OF MAIN DECK WITH TENDER ANNIE RUTH ALONGSIDE. COVER OF FORWARD COMPANIONWAY HAS BEEN PLACED ON MAIN DECK; SUN AWNING A TYPICAL FEATURE IN TROPICAL CLIMATES. CREW MEMBERS UNKNOWN Original 4-3/4'x6-3/4' photograph taken c. 1930? - Pilot Schooner "Alabama", Moored in harbor at Vineyard Haven, Vineyard Haven, Dukes County, MA

  4. Calvert Cliffs RELAP5/MOD3/SCDAP plant deck

    SciTech Connect

    Hendrix, C.E.; Determan, J.C.

    1992-12-01

    This report documents the development of a RELAP5/MOD3/SCDAP input deck for the Calvert Cliffs nuclear power plant. Through the addition of SCDAP inputs, NPA interactive capabilities, and significant nodalization enhancements the range of applicability; of this input deck has been greatly increased.

  5. Pilot Fullerton reviews checklist on Aft Flight Deck Onorbit Station

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Pilot Gordon Fullerton, wearing communications kit assembly (assy) mini headset, watches freefloating pen during checklist procedures at Aft Flight Deck Onorbit Station. Taken from the aft flight deck starboard side, Fullerton is seen in front of panels A7 and A8 with W8 and a 'United States Air Force - a Great Way of Life' decal overhead.

  6. 14 CFR 121.547 - Admission to flight deck.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...) AIR CARRIERS AND OPERATORS FOR COMPENSATION OR HIRE: CERTIFICATION AND OPERATIONS OPERATING... this section. (c) No person may admit any person to the flight deck unless there is a seat available.... (a) No person may admit any person to the flight deck of an aircraft unless the person being...

  7. 75 FR 44988 - Wire Decking From China; Determinations

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-07-30

    ... Commission, Washington, DC, and by publishing the notice in the Federal Register on January 28, 2010 (75 FR... COMMISSION Wire Decking From China; Determinations On the basis of the record \\1\\ developed in the subject... of wire decking from China, provided for in subheadings 9403.90.80, 7217.10, 7217.20, 7326.20,...

  8. 33 CFR 157.168 - Crew member: Main deck watch.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Crew member: Main deck watch. 157.168 Section 157.168 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... deck watch. During COW operations, the master shall ensure that at least one member of the crew with...

  9. 33 CFR 157.168 - Crew member: Main deck watch.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 33 Navigation and Navigable Waters 2 2014-07-01 2014-07-01 false Crew member: Main deck watch. 157.168 Section 157.168 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... deck watch. During COW operations, the master shall ensure that at least one member of the crew with...

  10. 33 CFR 157.168 - Crew member: Main deck watch.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Crew member: Main deck watch. 157.168 Section 157.168 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... deck watch. During COW operations, the master shall ensure that at least one member of the crew with...

  11. 33 CFR 157.168 - Crew member: Main deck watch.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 33 Navigation and Navigable Waters 2 2013-07-01 2013-07-01 false Crew member: Main deck watch. 157.168 Section 157.168 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... deck watch. During COW operations, the master shall ensure that at least one member of the crew with...

  12. 33 CFR 157.168 - Crew member: Main deck watch.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 33 Navigation and Navigable Waters 2 2012-07-01 2012-07-01 false Crew member: Main deck watch. 157.168 Section 157.168 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY... deck watch. During COW operations, the master shall ensure that at least one member of the crew with...

  13. 30. View of main deck at bow (looking aft from ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. View of main deck at bow (looking aft from samson post, upper deck removed), showing anchor windlass (left foreground), head (right foregound), and forward deckhouse; weather canopy overhead not an original or permanent feature - Schooner WAWONA, 1018 Valley Street, Seattle, King County, WA

  14. 22. VIEW OF DEBARKER FROM LOG INFEED DECK. NOTE ROOF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. VIEW OF DEBARKER FROM LOG IN-FEED DECK. NOTE ROOF SUPPORT OVER CARRIAGE AND LOG IN-FEED DECK IN UPPER RIGHT. (SEE OR-89-18 AND OR-89-23 FOR RELATED ARCHITECTURAL DETAILS.) - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

  15. VIEW OF DEBARKER FROM LOG INFEED DECK. NOTE ROOF SUPPORT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF DEBARKER FROM LOG IN-FEED DECK. NOTE ROOF SUPPORT OVER CARRIAGE AND LOG IN-FEED DECK IN UPPER RIGHT. (SEE OR-89-18 AND OR-89-23 FOR RELATED ARCHITECTURAL DETAILS.) - Hull-Oakes Lumber Company, 23837 Dawson Road, Monroe, Benton County, OR

  16. Astronaut Ellen Ochoa at RMS controls on aft flight deck

    NASA Technical Reports Server (NTRS)

    1994-01-01

    Astronaut Ellen Ochoa, payload commander, on the Space Shuttle Atlantis' aft flight deck, has just completed an operations at the controls for the Remote Manipulator System (RMS) arm while working in chorus with astronaut Donald R. McMonagle. McMonagle, mission commander, is seen here at his station on the forward flight deck. An RMS operations checklist floats in front of Ochoa.

  17. Development of ground-penetrating radar equipment for detecting pavement condition for preventive maintenance

    NASA Astrophysics Data System (ADS)

    Smith, S. S.; Scuillion, T.

    1993-10-01

    The report documents the development of a ground penetrating radar (GPR) system for locating potential maintenance problems in highway pavements. The report illustrates how GPR has the potential to detect four defects in pavements: stripping in an asphalt layer; moisture in base layer; voids or loss of support under rigid pavements; and overlay delamination.

  18. 76 FR 67018 - Notice to Manufacturers of Airport In-Pavement Stationary Runway Weather Information Systems

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-28

    ... Federal Aviation Administration Notice to Manufacturers of Airport In-Pavement Stationary Runway Weather... of In-Pavement Stationary Runway Weather Information Systems. SUMMARY: Projects funded under the... Active or Passive In- Pavement Stationary Runway Weather Information Systems that meet the...

  19. 23 CFR 972.208 - Federal lands pavement management system (PMS).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... “Pavement Management Guide,” AASHTO, 2001, is available for inspection as prescribed at 49 CFR part 7. It is... 23 Highways 1 2014-04-01 2014-04-01 false Federal lands pavement management system (PMS). 972.208....208 Federal lands pavement management system (PMS). In addition to the requirements provided in §...

  20. 78 FR 26847 - Including Specific Pavement Types in Federal-aid Highway Traffic Noise Analyses

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-08

    ... Federal Highway Administration Including Specific Pavement Types in Federal-aid Highway Traffic Noise...: The FHWA requests input from stakeholders and interested parties on expanding the specific pavement... data from three pavement types: dense-graded asphaltic concrete (DGAC), open-graded asphaltic...

  1. 23 CFR 972.208 - Federal lands pavement management system (PMS).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... “Pavement Management Guide,” AASHTO, 2001, is available for inspection as prescribed at 49 CFR part 7. It is... 23 Highways 1 2011-04-01 2011-04-01 false Federal lands pavement management system (PMS). 972.208....208 Federal lands pavement management system (PMS). In addition to the requirements provided in §...

  2. Hot in-place recycling of asphalt pavements. Master's thesis

    SciTech Connect

    Dowdy, M.L.

    1987-08-04

    The purpose of this report is to identify factors to consider in selecting a hot in-place recycling project for asphalt pavements. This report discusses the different types of recycling processes and several selected hot in-place recycling processes that are becoming so popular today. The types of asphalt pavement distress and their causes are discussed to provide a working knowledge of possible applications for this process. Discussions on project selection, design, and construction considerations will also provide an awareness of considerations relative to this type of asphalt-pavement rehabilitation. An understanding of these topics will be helpful when selecting hot in-place recycling. The information that this report is based upon was obtained from various sources. A literature search included technical reports, periodicals, and advertisements. Personal contact was made in the form of interviews with a number of representatives in the industry and on site inspection of Cutler Repaving, Inc. and Remixer Contracting Co., Inc. operations.

  3. An algorithm for pavement crack detection based on multiscale space

    NASA Astrophysics Data System (ADS)

    Liu, Xiang-long; Li, Qing-quan

    2006-10-01

    Conventional human-visual and manual field pavement crack detection method and approaches are very costly, time-consuming, dangerous, labor-intensive and subjective. They possess various drawbacks such as having a high degree of variability of the measure results, being unable to provide meaningful quantitative information and almost always leading to inconsistencies in crack details over space and across evaluation, and with long-periodic measurement. With the development of the public transportation and the growth of the Material Flow System, the conventional method can far from meet the demands of it, thereby, the automatic pavement state data gathering and data analyzing system come to the focus of the vocation's attention, and developments in computer technology, digital image acquisition, image processing and multi-sensors technology made the system possible, but the complexity of the image processing always made the data processing and data analyzing come to the bottle-neck of the whole system. According to the above description, a robust and high-efficient parallel pavement crack detection algorithm based on Multi-Scale Space is proposed in this paper. The proposed method is based on the facts that: (1) the crack pixels in pavement images are darker than their surroundings and continuous; (2) the threshold values of gray-level pavement images are strongly related with the mean value and standard deviation of the pixel-grey intensities. The Multi-Scale Space method is used to improve the data processing speed and minimize the effectiveness caused by image noise. Experiment results demonstrate that the advantages are remarkable: (1) it can correctly discover tiny cracks, even from very noise pavement image; (2) the efficiency and accuracy of the proposed algorithm are superior; (3) its application-dependent nature can simplify the design of the entire system.

  4. Experimental testing of a smart FRP-concrete composite bridge superstructure

    NASA Astrophysics Data System (ADS)

    Wang, Yanlei; Hao, Qingduo; Ou, Jinping

    2010-04-01

    A new kind of smart fiber reinforced polymer (FRP)-concrete composite bridge superstructure, which consists of two bridge decks and each bridge deck is comprised of four FRP box sections combined with a thin layer of concrete in the compression zone, was developed by using eight embedded FBG sensors in the top and bottom flanges of the FRP box sections at mid-span section of one bridge deck along longitudinal direction, respectively. The flexural behavior of the proposed smart composite bridge superstructure was experimentally studied in four-point loading. The longitudinal strains of the composite bridge superstructure were recorded using the embedded FBG sensors as well as the surfacebonded electric resistance strain gauges. Test results indicate that the FBG sensors can faithfully record the longitudinal strain of the composite bridge superstructure in tension at bottom flange of the FRP box sections or in compression at top flange over the entire loading range, as compared with the surface-bonded strain gauges. The proposed smart FRPconcrete composite bridge superstructure can monitor its longitudinal strains in serviceability limit state as well as in strength limit state, and will has wide applications for long-term monitoring in civil engineering.

  5. Impact of compressed natural gas fueled buses on street pavements

    SciTech Connect

    Yang, D.; Harrison, R.

    1995-07-01

    Capital Metro, the Ausin, Texas transit authority, is currently evaluating a number of CNG fueled buses. As part of the U.S. DOT Region Six University Transportation Centers Program (UTCP), a study was instigated into the scale of incremental pavement consumption associated with the operation of these buses. The study suggests that replacing current vehicles with CNG powered models utilizing aluminum storage tanks would raise average network equivalent single rehabilitation costs across the network of over four percent. Finally, it recommends that full cost study be undertaken with evaluation of the adoption of alternative bus fuels - which includes pavement and environmental impacts.

  6. Fatigue properties of rubber modified pavements. Final report

    SciTech Connect

    Raad, L.; Saboundjian, S.; Yuan, X.

    1995-05-01

    This report presents results of a study to determine the fatigue behavior of rubber modified pavements in Alaska in comparison with conventional asphalt concrete pavements. Laboratory studies were conducted on field specimens using the flexural fatigue test in the controlled-displacement mode. Tests were performed at 72 deg F and 40 deg F. Tested materials include (1) conventional HMA with AC 2.5 and AC 5; (2) PlusRide RUMAC with AC 5; (3) asphalt-rubber concrete with AC 2.5 (wet Process); and (4) rubberized asphalt-rubber concrete with AC 2.5 (wet/dry process).

  7. Thin, applied surfacing for improving skid resistance of concrete pavements

    NASA Astrophysics Data System (ADS)

    Scholer, C. F.

    1980-12-01

    The use of select aggregate in a thin wearing surface of portland cement mortar to prolone or restore a concrete pavement's ability to develop high friction was accomplished. Two fine aggregates, blast furnace slag and lightweight expanded shale were found to exhibit skid resistance greater than the other aggregates evaluated. The British polishing wheel was used in the laboratory evaluation of aggregate to simulate wear. The need for a method of restoring friction to a worn, but otherwise sound concrete pavement led to a field evaluation of several different techniques for placing a very thin overlay. The successful method was a broomed, very thin layer of mortar, 3 mm thick.

  8. Evaluation of multilayered pavement structures from measurements of surface waves

    USGS Publications Warehouse

    Ryden, N.; Lowe, M.J.S.; Cawley, P.; Park, C.B.

    2006-01-01

    A method is presented for evaluating the thickness and stiffness of multilayered pavement structures from guided waves measured at the surface. Data is collected with a light hammer as the source and an accelerometer as receiver, generating a synthetic receiver array. The top layer properties are evaluated with a Lamb wave analysis. Multiple layers are evaluated by matching a theoretical phase velocity spectrum to the measured spectrum. So far the method has been applied to the testing of pavements, but it may also be applicable in other fields such as ultrasonic testing of coated materials. ?? 2006 American Institute of Physics.

  9. Chaos theory analysis of a cable-stayed bridge: Part I. Finite element model development

    NASA Astrophysics Data System (ADS)

    Jin, Shuang; Livingston, Richard A.

    2007-04-01

    Cable-stayed bridges can exhibit large amplitude irregular stay cable oscillations under certain conditions of combined traffic flow and rain-wind loads that can pose severe risks to structural integrity. To investigate the mechanisms causing this behavior, a high fidelity nonlinear finite element model of a typical cable-stayed bridge has been developed using LS-DYNA based on the design of the Bill Emerson Memorial Bridge at Cape Girardeau, MO. The model uses over 540,000 finite elements representing 1254 bridge components to fully describe the detailed real geometry of the bridge tower, deck, stay cables, edge girders and floor-beam support girders. Traffic loads on the bridge deck are simulated by a Poisson Distributed Pulse (PDP) stochastic process model involving multi-lane traffic flows of more than 300 vehicles of various axle loads with varying arrival rates. The response data sets generated by the LS-DYNA simulations were then analyzed for chaotic behavior with the software CTBR. This extracts the nonlinear system invariants, the Lyapunov exponents, to identify the chaotic behavior from the dynamics of the structural system. The simulations showed positive Lyapunov exponents at various locations of the bridge deck and the bridge stay cable network. The analysis of these results revealed that even in the absence of strong rain-wind excitations the bridge deck vibration exhibits significant chaotic behavior that could excite the stay cables into a stronger chaotic regime, especially at the upper portion of the networked stay cables. This illustrates a phenomenon often ignored or unable to be captured by conventional linear dynamics analysis. Analysis of actual data sets collected from a monitoring network on the bridge also confirmed this chaotic behavior.

  10. Safer Bridges

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Safer bridges are among a number of spinoff benefits from NASA procedures for testing 'cfracture toughness" of a structural part, meaning its ability to -siscracktsh at might cause failure. The New River Bridge in West Virginia, shown under construction, is the world's largest single span bridge. U.S. Steel fracture toughness requirements for such bridges include NASA-developed test procedures. Bridge materials and other metal structures may develop flaws during their service lifetimes. Such flaws can affect the structural integrity of the part. Thus, it is important to know the "fracture toughness" of a structural part, or its ability to resist cracks. NASA has long experience in developing fracture toughness tests for aerospace hardware. Since 1960, NASA-Lewis has worked closely with the American Society for Testing & Materials. Lewis and NASA-funded industrial contractors have made many important contributions to test procedures, now recommended by ASTM, for measuring fracture toughness.

  11. Airfield Rigid Pavement Structural DesignA Review of Main Aspects and Methods of Analysis

    NASA Astrophysics Data System (ADS)

    Tiago Bonucci, Pereira

    2010-05-01

    Airfield pavements present a number of characteristics that make their design considerably different from that of road pavements. Apart from load magnitude and it's frequency, maintenance issues and pavement strength classification reporting are aspects that must be considered in the design phase. In the present paper, these aspects are analysed in the light of traditional and new methods of airfield pavement analysis. Parametric studies are performed in order to study the effects of different factors, such as pavement structure, layer thickness, material strength, effects of temperature, load transfer across joints and traffic characteristics.

  12. Vibration of vehicle-pavement coupled system based on a Timoshenko beam on a nonlinear foundation

    NASA Astrophysics Data System (ADS)

    Ding, Hu; Yang, Yan; Chen, Li-Qun; Yang, Shao-Pu

    2014-12-01

    This paper focuses on the coupled nonlinear vibration of vehicle-pavement system. The pavement is modeled as a Timoshenko beam resting on a six-parameter foundation. The vehicle is simplified as a spring-mass-damper oscillator. For the first time, the dynamic response of vehicle-pavement coupled system is studied by modeling the pavement as a Timoshenko beam resting on a nonlinear foundation. Consequently, the shear effects and the rotational inertia of the pavement are included in the modeling process. The pavement model is assumed to be a linear-plus-cubic Pasternak-type foundation. Furthermore, the convergent Galerkin truncation is used to obtain approximate solutions to the coupled vibratory response of the vehicle-pavement coupled system. The dynamic responses of the vehicle-pavement system with the asphalt pavement on soft soil foundation are investigated via the numerical examples. The numerical results show that the calculation for the coupled vibratory response needs high-order modes. Moreover, the coupling effects between the pavement and the vehicle are numerically examined by using the convergent modal truncation. The physical parameters of the vehicle-pavement system such as the shear modulus are compared for determining their influences on the coupled vibratory response.

  13. Deterioration modeling for condition assessment of flexible pavements considering extreme weather events

    NASA Astrophysics Data System (ADS)

    Hashemi Tari, Yasamin; Shahini Shamsabadi, Salar; Birken, Ralf; Wang, Ming

    2015-04-01

    Accurate pavement management systems are essential for states' Department Of Transportation and roadway agencies to plan for cost-effective maintenance and repair (M and R) strategies. Pavement deterioration model is an imperative component of any pavement management system since the future budget and M and R plans would be developed based on the predicted pavement performance measures. It is crucial for the pavement deterioration models to consider the factors that significantly aggravate the pavement condition. While many studies have highlighted the impact of different environmental, load, and pavement's structure on the life cycle of the pavement, effect of extreme weather events such as Floods and Snow Storms have often been overlooked. In this study, a pavement deterioration model is proposed which would consider the effect of traffic loads, climate conditions, and extreme weather events. Climate, load and performance data has been compiled for over twenty years and for eight states using the Long Term Pavement Performance (LTPP) and National Oceanic and Atmospheric Administration (NOAA) databases. A stepwise regression approach is undertaken to quantify the effect of the extreme weather events, along with other influential factors on pavement performance in terms of International Roughness Index (IRI). Final results rendered more than 90% correlation with the quantified impact values of extreme weather events.

  14. Desert pavements and associated rock varnish in the Mojave Desert: How old can they be?

    NASA Astrophysics Data System (ADS)

    Quade, Jay

    2001-09-01

    Desert pavements are common features of arid landscapes and have been widely used as a relative age indicator of the geomorphic surfaces upon which they are developed. In this study I examined the patterns of pavement development as a function of elevation in the Mojave Desert as well as the causes for the gradual disappearance of pavement at high elevations. Pavement density, as measured by percentage of pebble coverage, decreases systematically with elevation gain by 3% per 100 m, from 95% coverage below 500 m to less than 60% at 1700 m. Plants appear to be the main agent of pavement disruption; plant density decreases as pavement density increases. Burrowing by rodents and crusting by cryptobiota also disrupt pavement development at higher elevation. During the last glacial maximum, plant communities were displaced 1000 1400 m downward in the Mojave Desert. Pavements today generally do not survive above the blackbush (Coleogyne ramossisma)-sagebrush (Artemisia tridentata) zone. Evidence from packrat middens shows that these and other plants typical of high elevations today grew as low as 300 400 m during the last glacial maximum. I suggest that during the last glacial maximum, desert pavements were confined to the lowest alluvial fans of Death Valley and adjoining low valleys. No alluvial desert pavements above 400 m in the region are older than the latest Pleistocene. By the same reasoning, desert varnish on desert pavements above 400 m may all be Holocene in age, except where developed on stable boulders.

  15. Functionality Enhancement of Industrialized Optical Fiber Sensors and System Developed for Full-Scale Pavement Monitoring

    PubMed Central

    Wang, Huaping; Liu, Wanqiu; He, Jianping; Xing, Xiaoying; Cao, Dandan; Gao, Xipeng; Hao, Xiaowei; Cheng, Hongwei; Zhou, Zhi

    2014-01-01

    Pavements always play a predominant role in transportation. Health monitoring of pavements is becoming more and more significant, as frequently suffering from cracks, rutting, and slippage renders them prematurely out of service. Effective and reliable sensing elements are thus in high demand to make prognosis on the mechanical properties and occurrence of damage to pavements. Therefore, in this paper, various types of functionality enhancement of industrialized optical fiber sensors for pavement monitoring are developed, with the corresponding operational principles clarified in theory and the performance double checked by basic experiments. Furthermore, a self-healing optical fiber sensing network system is adopted to accomplish full-scale monitoring of pavements. The application of optical fiber sensors assembly and self-healing network system in pavement has been carried out to validate the feasibility. It has been proved that the research in this article provides a valuable method and meaningful guidance for the integrity monitoring of civil structures, especially pavements. PMID:24854060

  16. Installation of bridge monitoring systems in Connecticut

    NASA Astrophysics Data System (ADS)

    Lauzon, Robert; DeWolf, John T.

    1996-11-01

    The Connecticut Department of Transportation (ConnDOT) has undertaken a major initiative to install permanent remotely- accessible monitoring systems on seven in-service highway bridges. These systems will consist of either a Roadway Weather Information System (RWIS), or Structural Monitoring System (SMS), or both, depending on the structure type and/or location. The RWIS provides weather related information regarding the pavement on and off the structure and ambient weather conditions at the bridge site. Systems like this are commercially available and in use throughout the country assisting transportation agencies in performing winter maintenance operations. The SMS is the product of cooperative research at the University of Connecticut and ConnDOT. The University has specified, installed and operated a prototype vibrational-based monitoring system on tow in-service bridges during separate year-long studies. The planned SMS, modeled after the prototype, includes accommodations for a variety of sensors including strain, tilt, structural temperature and vibration. The ultimate goal of this work is to develop a generic platform for a remote bridge monitoring system which can be adapted to any bridge with any combination of sensors and sensor types. Such a system would benefit both the safety and management of these structures. Current activity along with background information are discussed.

  17. Interior view of the Flight Deck looking forward, the Commander's ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of the Flight Deck looking forward, the Commander's seat and controls are on the left and the pilot's seat and controls are on the right of the view. Note that the flight deck windows have protective covers over them in this view. This images can be digitally stitched with image HAER No. TX-116-A-20 to expand the view to include the overhead control panels of the flight deck. This view was taken in the Orbiter Processing Facility at the Kennedy Space Center. - Space Transportation System, Orbiter Discovery (OV-103), Lyndon B. Johnson Space Center, 2101 NASA Parkway, Houston, Harris County, TX

  18. DEVELOPMENT OF A HYDROPHOBIC SUBSTANCE TO MITIGATE PAVEMENT ICE ADHESION

    EPA Science Inventory

    The specific problem to which this report is addressed is the development of a hydrophobic substance to mitigate the adhesion of ice to pavement as an alternative to deicing chemicals. The factors involved in evaluating this concept are the following: Economics; safety; environme...

  19. Alternative aircraft loading index for pavement structural analysis

    SciTech Connect

    Loizos, A.; Charonitis, G.

    1999-05-01

    The most common practical way to simplify the structural analysis of airfield pavements is the use of equivalent single wheel load models instead of the actual gear of the aircrafts. As the accuracy and reliability of these models strongly affects the design and evaluation of airfield pavements, there is considerable need to investigate both system approaches. The first one, which uses a constant value for the pressure while the radius is variable, is currently under use by the aircraft classification number-pavement classification number method of the International Civil Aviation Organization, but despite this fact it proved to be inadequate to express the aircraft loading in many situations. On the contrary, according to this study, the second model, which has a constant value for the radius while the pressure varies, is more reliable, and it can be an interesting alternative. Thus, based on this model, an aircraft loading index is introduced, which aims to be a simple and reliable factor for expressing the severity of the loading of the aircrafts and a utility for several matters related to the airfield pavement applications.

  20. Nitrogen Transformations in Three Types of Permeable Pavement

    EPA Science Inventory

    In 2009, USEPA constructed a 0.4-ha (1-ac) parking lot at the Edison Environmental Center in Edison, NJ, that incorporated three different permeable pavement types - permeable interlocking concrete pavers (PICP), pervious concrete (PC), and porous asphalt (PA). The driving lanes...