WorldWideScience

Sample records for bridge deck construction

  1. Construction of crack-free bridge decks.

    Science.gov (United States)

    2017-04-01

    This serves as the final report on Transportation Pooled-Fund Program Project No. TPF-5(174), Construction : of Crack-Free Bridge Decks. The goal of the study was to implement the most cost-effective techniques for : improving bridge deck life ...

  2. Construction of crack-free bridge decks : technical summary.

    Science.gov (United States)

    2017-04-01

    The report documents the performance of the decks based on crack surveys performed on the LC-HPC decks and : matching control bridge decks. The specifications for LC-HPC bridge decks, which cover aggregates, concrete, : and construction procedures, a...

  3. Deck forms for bridge construction safety.

    Science.gov (United States)

    2007-08-31

    Because I-girders have inherently weak torsion resistance, cross-frames and/or diaphragms are placed at close : spacing intervals to minimize the susceptibility of individual girders to instability during construction. A recent : increase in fatigue ...

  4. Fiberglass reinforced polymer composite bridge deck construction in Illinois

    Science.gov (United States)

    2002-09-01

    An experiment was conducted using a fiber reinforced polymer composite material for the bridge deck of a low volume bridge. The test location was on South Fayette Street over the Town Brook in Jacksonville, Illinois. This project included removal of ...

  5. Latex-modified fiber-reinforced concrete bridge deck overlay : construction/interim report.

    Science.gov (United States)

    1993-06-01

    Latex-modified concrete (LMC) is Portland cement concrete (PCC) with an admixture of latex. LMC is considered to be nearly impermeable to chlorides and is extensively used to construct bridge deck overlays. Unfortunately, some of these overlays have ...

  6. 3D laser scanning for quality control and assurance in bridge deck construction.

    Science.gov (United States)

    2014-08-01

    The inspection of installations of rebar and other embedded components in bridge deck construction is a tedious : task for eld inspectors, requiring considerable eld time for measurement and verication against code requirement. The verica...

  7. Design, installation, and condition assessment of a concrete bridge deck constructed with ASTM A1035 CS no. 4 bars.

    Science.gov (United States)

    2017-06-01

    Recently developed corrosion-resistant reinforcing structural design guidelines were used to design, construct, and : assess a reinforced concrete bridge deck with high-strength ASTM A1035 CS steel bars. The bridge replacement is located : along the ...

  8. Linear Cracking in Bridge Decks

    Science.gov (United States)

    2018-03-01

    Concrete cracking in bridge decks remains an important issue relative to deck durability. Cracks can allow increased penetration of chlorides, which can result in premature corrosion of the reinforcing steel and subsequent spalling of the concrete de...

  9. Performance evaluation of Iowa bridge decks constructed with epoxy-coated reinforcing bars.

    Science.gov (United States)

    2011-08-01

    Epoxy coatings have been used on the embedded reinforcing bars of bridge decks since the mid-1970s to : mitigate deterioration caused by chloride-induced corrosion. The use of chloride-based deicers became : common in the early 1960s and caused corro...

  10. Exodermic bridge deck performance evaluation.

    Science.gov (United States)

    2010-07-01

    In 1998, the Wisconsin DOT completed a two"leaf bascule bridge in Green Bay with an exodermic deck system. The exodermic deck consisted of 4.5"in thick cast"in"place reinforced concrete supported by a 5.19"in tall unfilled steel grid. The concrete an...

  11. Laboratory testing and finite element modeling of precast bridge deck panel transverse connections.

    Science.gov (United States)

    2010-08-06

    Precast bridge deck panels are increasingly used to reduce construction times and associated traffic delays as part of many DOTs push for accelerated bridge construction. They allow a bridge deck to be built or replaced in days instead of months. ...

  12. Fiber reinforced polymer bridge decks : [technical summary].

    Science.gov (United States)

    2011-01-01

    A number of researchers have addressed the use of Fiber Reinforced Polymer (FRP) deck as a replacement solution for deteriorated bridge decks made of traditional materials. The use of new, advanced materials such as FRP is advantageous when the bridg...

  13. Hydraulic forces on submerged bridge decks.

    Science.gov (United States)

    2008-09-01

    Bridge decks can be subjected to large horizontal forces when overtopping occurs. These forces may result in the displacement of bridge decks from the bents. This paper reports on the results of a laboratory study of horizontal forces on bridge decks...

  14. Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge

    Science.gov (United States)

    L. E. Hislop; M. A. Ritter

    The Connell Lake bridge was constructed in early 1991 on the Tongass National Forest, Alaska, as a demonstration bridge under the Timber Bridge Initiative. The bridge is a stress-laminated deck structure with an approximate 36-ft length and 18-ft width and is the first known stress-laminated timber bridge constructed in Alaska. Performance of the bridge was monitored...

  15. Hydrodynamic forces on inundated bridge decks

    Science.gov (United States)

    2009-05-01

    The hydrodynamic forces experienced by an inundated bridge deck have great importance in the design of bridges. Specifically, the drag force, lift force, and the moment acting on the bridge deck under various levels of inundation and a range of flow ...

  16. Field performance of timber bridges. 4, Graves Crossing stress-laminated deck bridge

    Science.gov (United States)

    J. P. Wacker; M. A. Ritter

    The Graves Crossing bridge was constructed October 1991 in Antrim County, Michigan, as part of the demonstration timber bridge program sponsored by the USDA Forest Service. The bridge is a two-span continuous, stress-laminated deck superstructure and it is 36-ft long and 26-ft wide. The bridge is one of the first stress-laminated deck bridges to be built of sawn lumber...

  17. Shrinkage and durability study of bridge deck concrete.

    Science.gov (United States)

    2010-12-01

    The Mississippi Department of Transportation is incorporating changes to material : specifications and construction procedures for bridge decks in an effort to reduce shrinkage : cracking. These changes are currently being implemented into a limited ...

  18. Smart FRP Composite Sandwich Bridge Decks in Cold Regions

    Science.gov (United States)

    2011-07-01

    In this study, new and integrated Smart honeycomb Fiber-Reinforced Polymer (S-FRP) : sandwich materials for various transportation construction applications, with particular emphasis : on highway bridge decks in cold regions, were developed and teste...

  19. Steel plate reinforcement of orthotropic bridge decks

    NARCIS (Netherlands)

    Teixeira de Freitas, S.

    2012-01-01

    The PhD research is focused on the reinforcement of fatigue cracked orthotropic steel bridge decks (OBD) by adding a second steel plate to the existing deck. The main idea is to stiffen the existing deck plate, which will reduce the stresses at the fatigue sensitive details and extend the fatigue

  20. Field performance of timber bridges. 5, Little Salmon Creek stress-laminated deck bridge

    Science.gov (United States)

    M. A. Ritter; J. A. Kainz; G. J. Porter

    The Little Salmon Creek bridge was constructed in November 1988 on the Allegheny National Forest in Pennsylvania. The bridge is a simple span, single-lane, stress-laminated deck superstructure that is approximately 26-ft long and 16-ft wide. The bridge is unique in that it is the first known stress-laminated timber bridge to be constructed of hardwood lumber. The...

  1. Field performance of timber bridges. 6, Hoffman Run stress-laminated deck bridge

    Science.gov (United States)

    M. A. Ritter; P. D. Hilbrich Lee; G. J. Porter

    The Hoffman Run bridge, located just outside Dahoga, Pennsylvania, was constructed in October 1990. The bridge is a simple-span, single-lane, stress-laminated deck superstructure that is approximately 26 ft long and 16 ft wide. It is the second stress-laminated timber bridge to be constructed of hardwood lumber in Pennsylvania. The performance of the bridge was...

  2. Experimental evaluation and field implementation of FRP bridge deck modules

    Directory of Open Access Journals (Sweden)

    Woraphot Prachasaree

    2008-07-01

    Full Text Available Construction of highway bridge decks using fiber reinforced polymer (FRP composite deck and superstructuremodules in lieu of concrete decks has proven to be feasible. However, FRP’s are not widely accepted yet despite theirbenefits such as non-corrosiveness, higher strength to weight ratio, and better fatigue resistance than conventional materials.Lack of wider usage of FRP material is mainly attributed to the absence of: 1 standardized test procedures, 2 designspecifications, and 3 construction procedures. The higher initial cost is also inhibiting bridge engineers in selecting FRPmodules as highway bridge super structural systems.Implementation of FRP composites technology for highway bridge decks leads to higher safety and lower life cyclecosts. Significant ongoing research and development of FRP deck modules as illustrated herein, has proven to enhancedeck module properties in developing FRP modules with enhanced structural performance.Prodeck 4 is one such multicellular deck that was recently developed, and extensively evaluated for static and fatigueloads, and its response results are presented herein. From rigorous testing, it was concluded that Prodeck 4 could resistAASHTO HS 25 loading with maximum stringer spacing of 48 inches. This led to construction of two bridges (one in Ohioand other in West Virginia using Prodeck 4 as decking.

  3. Field performance of timber bridges. 8, Lynches Woods Park stress-laminated deck bridge

    Science.gov (United States)

    J. P. Wacker; M. A. Ritter; D. Conger

    The Lynches Woods Park bridge was constructed during the summer of 1990 in Newberry, South Carolina. It is a single-span, single-lane, stress-laminated deck superstructure that measures approximately 30 ft long, 16 ft wide, and 14 in. deep. The bridge is unique in that is one of the first known stress-laminated deck bridges to be constructed of Southern Pine lumber...

  4. Evaluation and analysis of decked bulb T beam bridges.

    Science.gov (United States)

    2015-03-01

    A new corrosion-free decked bulb T beam bridge system has been developed to overcome some of the problems : associated with the construction of side-by-side box beam bridges such as the lack of inspection space between : beams and the longitudinal de...

  5. Investigation of Aerodynamic Interference between Twin Deck Bridges

    Energy Technology Data Exchange (ETDEWEB)

    Sitek, M. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Bojanowski, C. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC); Lottes, S. A. [Argonne National Lab. (ANL), Argonne, IL (United States). Energy Systems Division. Transportation Research and Analysis Computing Center (TRACC)

    2016-05-01

    Construction of a twin bridge can be a cost effective and minimally disruptive way to increase capacity when an existing bridge is not near the end of its service life. With ever growing vehicular traffic, when demand approaches the capacity of many existing roads and bridges. Remodeling a structure with an insufficient number of lanes can be a good solution in case of smaller and less busy bridges. Closing down or reducing traffic on crossings of greater importance for the construction period, however, can result in major delays and revenue loss for commerce and transportation as well as increasing the traffic load on alternate route bridges. Multiple-deck bridges may be the answer to this issue. A parallel deck can be built next to the existing one, without reducing the flow. Additionally, a new bridge can be designed as a twin or multi-deck structure. Several such structures have been built throughout the United States, among them: - The New NY Bridge Project - the Tappan Zee Hudson River Crossing, - SR-182 Columbia River Bridge, - The Thaddeus Kosciusko Bridge (I-87), - The Allegheny River Bridge, Pennsylvania, which carries I76, - Fred Hartman Bridge, TX, see Figure 1.2. With a growing number of double deck bridges, additional, more detailed, studies on the interaction of such bridge pairs in windy conditions appears appropriate. Aerodynamic interference effects should be examined to assure the aerodynamic stability of both bridges. There are many studies on aerodynamic response of single deck bridges, but the literature on double-deck structures is not extensive. The experimental results from wind tunnels are still limited in number, as a parametric study is required, they can be very time consuming. Literature review shows that some investigation of the effects of gap-width and angle of wind incidence has been done. Most of the CFD computational studies that have been done were limited to 2D simulations. Therefore, it is desirable to investigate twin decks

  6. Field performance of timber bridges. 15, Pueblo County, Colorado, stress-laminated deck bridge

    Science.gov (United States)

    L. E. Hislop

    The Pueblo County 204B bridge was constructed in March 1990 in Pueblo, Colorado, as a demonstration bridge under the USDA Forest Service Timber Bridge Initiative. The stress-laminated deck superstructure is approximately 10 m long, 9 m wide, and 406 mm deep, with a skew of 10 degrees. Performance monitoring was conducted for 3 years, beginning at...

  7. Analysis of Biaxially Stressed Bridge Deck Plates

    DEFF Research Database (Denmark)

    Jönsson, Jeppe; Bondum, Tommi Højer

    2012-01-01

    The ultimate state analysis of bridge deck plates at the intersection zone between main girders and transverse beams is complicated by biaxial membrane stresses, which may be in compression or tension in either direction depending on the bridge configuration and the specific location. This paper...

  8. Gust loading on streamlined bridge decks

    DEFF Research Database (Denmark)

    Larose, Guy; Mann, Jakob

    1998-01-01

    The current analytical description of the buffeting action of wind on long-span bridges is based on the strip assumption. However, recent experiments on closed-box girder bridge decks have shown that this assumption is not valid and is the source of an important part of the error margin...... of the analytical prediction methods. In this paper, an analytical model that departs from the strip assumption is used to describe the gust loading on a thin airfoil. A parallel is drawn between the analytical model and direct measurements of gust loading on motionless closed-box girder bridge decks. Empirical...

  9. Field investigation of the corrosion protection performance of bridge decks and piles constructed with epoxy-coated reinforcing steel in Virginia.

    Science.gov (United States)

    1997-10-01

    The corrosion protection performance of epoxy-coated reinforcing steel (ECR) was assessed in three bridge decks and the piles : in three marine structures in Virginia in 1996. The decks were 17 years old, two of the marine structures were 8 years old...

  10. Fiber reinforced polymer bridge decks.

    Science.gov (United States)

    2011-01-01

    The overarching goal of this study was to perform a comprehensive evaluation of various issues related to the strength and serviceability : of the FRP deck panels that are available in the industry. Specific objectives were to establish critical limi...

  11. Demonstration and Validation of a Lightweight Composite Bridge Deck Technology as an Alternative to Reinforced Concrete

    Science.gov (United States)

    2016-08-01

    Abstract Cyclic loading and weathering of reinforced concrete bridge decks cause corrosion of reinforcement steel, which leads to cracking , potholes...economic analysis in terms of return on investment (ROI). The main problems identified after construction were reflective cracking of the polymer...flange and bottom of deck). ..................... 21 Figure 22. Foam grout dams in pultruded deck section

  12. Field performance of timber bridges. 9, Big Erick`s stress-laminated deck bridge

    Science.gov (United States)

    J. A. Kainz; J. P. Wacker; M. Nelson

    The Big Erickas bridge was constructed during September 1992 in Baraga County, Michigan. The bridge is 72 ft long, 16 ft wide, and consists of three simple spans: two stress-laminated deck approach spans and a stress-laminated box center span. The bridge is unique in that it is one of the first known stress-laminated timber bridge applications to use Eastern Hemlock...

  13. Field performance of timber bridges. 10, Sanborn Brook stress-laminated deck bridge

    Science.gov (United States)

    P. D. Hilbrich Lee; J. P. Wacker; M. A. Ritter

    The Sanborn Brook bridge was constructed in August 1991, 10 miles northeast of Concord, New Hampshire, as part of the demonstration timber bridge program of the USDA Forest Service. The bridge is a simple-span, double-lane, stress-laminated deck superstructure constructed from Southern Pine lumber and is approximately 25 ft long and 28 ft wide with a skew of 14 degrees...

  14. Stochastic Assessment of Nigerian Wood for Bridge Decks | Owoeye ...

    African Journals Online (AJOL)

    This presentation assures the suitability of Nigerian wood using a stochastic safety evaluation method for bridge decks. A timber bridge deck is modeled in accordance to current specifications, to represent real life experiment in order to depict the structural behavior of planks when used as bridge decks. This model is then ...

  15. Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction

    Science.gov (United States)

    2017-09-01

    Concrete bridge decks are directly exposed to daily traffic loads and may experience some surface cracking caused by excessive stress or fatigue accumulation, which requires repair or replacement. Among typical bridges in North America, bridge decks ...

  16. Field performance of timber bridges. 17, Ciphers stress-laminated deck bridge

    Science.gov (United States)

    James P. Wacker; James A. Kainz; Michael A. Ritter

    In September 1989, the Ciphers bridge was constructed within the Beltrami Island State Forest in Roseau County, Minnesota. The bridge superstructure is a two-span continuous stress-laminated deck that is approximately 12.19 m long, 5.49 m wide, and 305 mm deep (40 ft long, 18 ft wide, and 12 in. deep). The bridge is one of the first to utilize red pine sawn lumber for...

  17. The effects of temperature on fiber composite bridge decks.

    Science.gov (United States)

    2009-01-01

    In this study the fiber composite bridge decks were subjected to thermal gradients to obtain the temperature difference between the top and bottom surface of the decks and to determine the thermal properties of the deck. The fiber composite bridge de...

  18. The effect of bridge deck design methodology on crack control.

    Science.gov (United States)

    2010-01-30

    At present, the Idaho Transportation Department (ITD) Bridge Design Manual allows engineers to use the AASHTO empirical method to : design concrete bridge decks. However, the ITD Bridge Section would like to compare their design practices to those em...

  19. Cracking behavior of structural slab bridge decks

    Science.gov (United States)

    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.

  20. Aerodynamic and aeroelastic characteristics of typical bridge decks equipped with wind barriers at the windward bridge-deck edge

    Czech Academy of Sciences Publication Activity Database

    Buljac, Andrija; Kozmar, H.; Pospíšil, Stanislav; Macháček, Michael

    2017-01-01

    Roč. 137, April (2017), s. 310-322 ISSN 0141-0296 R&D Projects: GA ČR(CZ) GA15-01035S; GA MŠk(CZ) LO1219 Keywords : bridge decks * roadway wind barrier * aerodynamic forces and moments * galloping * flutter * wind-tunnel experiments Subject RIV: JM - Building Engineering OBOR OECD: Construction engineering, Municipal and structural engineering Impact factor: 2.258, year: 2016 http://www.sciencedirect.com/science/ article /pii/S014102961730278X

  1. Dynamic assessment of bridge deck performance considering realistic bridge-traffic interaction : research brief

    Science.gov (United States)

    2017-09-01

    This study is to develop simulation methodology to conduct the dynamic assessment of bridge deck performance subjected to traffic. Concrete bridge decks are exposed to daily traffic loads and may experience some surface cracking caused by excessive s...

  2. Experimental studies on multicellular GFRP bridge deck panels ...

    Indian Academy of Sciences (India)

    M P MUTHURAJ

    2017-11-20

    Nov 20, 2017 ... design of a new bridge deck panel made of GFRP. Zhu and. Lopez [9] ... than that for a concrete deck, as demonstrated by Daniel. [18] and Resins et al ... waste prevention or reduction;. • re-use;. • material recycling;. • energy recovery;. • landfill/disposal. FRP decks are generally prefabricated by various effi-.

  3. Multidisciplinary health monitoring of a steel bridge deck structure

    NARCIS (Netherlands)

    Pahlavan, P.L.; Pijpers, R.J.M.; Paulissen, J.H.; Hakkesteegt, H.C.; Jansen, T.H.

    2013-01-01

    Fatigue cracks in orthotropic bridge decks are an important cause for the necessary renovation of existing bridges. Parallel utilization of various technologies based on different physical sensing principles can potentially maximize the efficiency of structural health monitoring (SHM) systems for

  4. Precision monitoring of bridge deck curvature change during replacement.

    Science.gov (United States)

    2016-05-01

    This project was focused on development and deployment of a system for monitoring vertical : displacement in bridge decks and bridge spans. The system uses high precision wireless inclinometer : sensors to monitor inclinations at various points of a ...

  5. Overload truck wheel load distribution on bridge decks.

    Science.gov (United States)

    2009-04-01

    There is a need to accurately analyze the load effects on bridge decks from permitted overload trucks on : Michigans roads. The AASHTO Standard Specifications for Highway Bridges, 17th edition, provides a : distribution width of live loads when re...

  6. Evaluation of the environmental impact of bridge deck runoff.

    Science.gov (United States)

    2012-12-01

    Bridges are located in very close proximity to receiving waters, and regulatory agencies often require specific stormwater : control measures for bridge deck runoff. While there is some information available on roadway runoff, few studies have : focu...

  7. Spalling solution of precast-prestressed bridge deck panels.

    Science.gov (United States)

    2010-10-01

    This research has examined spalling of several partial-depth precast prestressed concrete (PPC) bridge decks. It was recently obser : that some bridges with this panel system in the MoDOT inventory have experienced rusting of embedded steel reinforce...

  8. Reduction of Bridge Deck Cracking through Alternative Material Usage

    Science.gov (United States)

    2017-12-01

    ODOT routinely deploys a large number of continuous span structural slab bridges. Despite being designed to strictly satisfy all the relevant AASHTO and ODOT BDM requirements, many such bridge decks show transverse cracks, with widths greater than th...

  9. Rapid replacement of bridge deck expansion joints study - phase I.

    Science.gov (United States)

    2014-12-01

    Bridge deck expansion joints are used to allow for movement of the bridge deck due to thermal expansion, dynamics loading, and : other factors. More recently, expansion joints have also been utilized to prevent the passage of winter de-icing chemical...

  10. TSUNAMI WAVE LOADING ON A BRIDGE DECK WITH PERFORATIONS

    Directory of Open Access Journals (Sweden)

    P. Lukkunaprasit

    2011-01-01

    Full Text Available Tsunamis have damaged bridges to various extents in the 2004 Indian Ocean Tsunami. This paper reports an experimental investigation of the effect of perforations in the girders and parapets on the horizontal tsunami loads. The results reveal that the maximum pressures impinging on the front face of the pier and deck are 4.5 and 3 times the hydrostatic pressure at 80mm nominal wave heights. The percentage of force reduction of the bridge deck with 10% perforated girders and 60% perforated parapets is found to be close to the percentage of perforation area in the deck. However, it is also noted that perforations in the bridge deck can substantially reduce the tsunami forces acting on it throughout the force time history. Thus, less damage to the bridge is anticipated for the bridge deck with perforations in girders and parapets.

  11. The future of rapid bridge deck replacement.

    Science.gov (United States)

    2015-06-01

    Replacing aging, deteriorated infrastructure often requires road closures and traffic detours which impose : inconvenience and delay on commerce and members of the motoring public. Accelerated bridge construction : techniques often use precast member...

  12. Analytical and experimental evaluation of an aluminum bridge deck panel. Part 2, failure analysis.

    Science.gov (United States)

    1999-01-01

    Aluminum bridge decks may prove to be an alternative to concrete decks for improving the performance of structural bridge systems. Combining excellent corrosion resistance with extremely low density, aluminum decks can prolong surface life, facilitat...

  13. To the question of reliability and durability ballastless deck of bridge

    Directory of Open Access Journals (Sweden)

    V.V. Prystynskaya

    2012-12-01

    Full Text Available The principal causes of operational defects in bridge ballastless deck plates are considered in the article. The drawbacks of these plates construction that prevent from achieving a higher level of bridge framework reliability and durability have been analysed.

  14. Experimental studies on multicellular GFRP bridge deck panels ...

    Indian Academy of Sciences (India)

    M P MUTHURAJ

    2017-11-20

    Nov 20, 2017 ... cellular glass fibre reinforced polymer (GFRP) composite bridge deck panels under static and fatigue loading. Various ... deck panels of size 1250 mm 9 333 mm 9 150 mm (l 9 b 9 d) were fabricated by hand lay-up process and tested for static .... Carbon dioxide emission is one of the important aspects to.

  15. A feasibility study of bridge deck deicing using geothermal energy.

    Science.gov (United States)

    2015-04-01

    In this study, we investigated the feasibility of a ground-coupled system that utilizes heat energy harvested from the ground for : deicing of bridge decks. Heat exchange is performed using circulation loops integrated into the deep foundations suppo...

  16. Bridge deck concrete volume change : final contract report.

    Science.gov (United States)

    2010-02-01

    Concrete structures such as bridge decks, with large surface area relative to volume, shrink and crack, thus reducing service life performance and increasing operation costs. The project evaluated the early, first 24 hours, and long-term, 180 days, s...

  17. Evaluation of bridge deck with shrinkage-compensating concrete.

    Science.gov (United States)

    2016-04-01

    Concrete bridge decks are susceptible to premature cracking and to corrosion of reinforcing steel. Low-permeability : concrete does not always ensure durability if the concrete has excessive cracks that facilitate the intrusion of aggressive solution...

  18. Investigation of silica fume concrete bridge deck overlay failures.

    Science.gov (United States)

    2016-02-23

    Many of these microsilica-modified concrete or silica fume concrete (SFC) bridge deck overlays across the State of Wyoming are suffering from premature distress that includes random cracking, loss of bond and delaminations. To determine the most like...

  19. Empirical deck for phased construction and widening [summary].

    Science.gov (United States)

    2017-06-01

    The most common method used to design and analyze bridge decks, termed the traditional : method, treats a deck slab as if it were made of strips supported by inflexible girders. An : alternative the empirical method treats the deck slab as a ...

  20. Smart FRP Composite Sandwich Bridge Decks in Cold Regions

    Science.gov (United States)

    2011-07-01

    What if every time a bridge on a lonely road got icy, it automatically notified the local DOT to begin ice-control safety measures? What if a bridge could tell someone : every time an overloaded truck hit the decking, or when the trusses under it beg...

  1. Fatigue classification of welded joints in orthotropic steel bridge decks

    NARCIS (Netherlands)

    Kolstein, M.H.

    2007-01-01

    This dissertation presents the research into fatigue classifications of welded joints in orthotropic steel bridge decks. These classifications are needed to calculate the fatigue life of these joints and should be included in the design codes. For years bridge design was mainly based on static

  2. Service Life and Maintenance Modelling of Reinforced Concrete Bridge Decks

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    Recent research in the area of assessment and maintenance of reinforced concrete bridge decks is presented in this paper. Three definitions of service lifetime are introduced and the difficult problem of assessing the service life is discussed. A stochastic modelling of corrosion and corrosion cr...... cracking is introduced and the site dependency of corrosion is stressed. Finally, a recently developed optimal repair strategy for bridges is briefly explained.......Recent research in the area of assessment and maintenance of reinforced concrete bridge decks is presented in this paper. Three definitions of service lifetime are introduced and the difficult problem of assessing the service life is discussed. A stochastic modelling of corrosion and corrosion...

  3. Field instrumentation and measured response of the I-295 cable-stayed bridge : interim report on construction measurements in deck segments.

    Science.gov (United States)

    1991-01-01

    During the construction of the I-295 cable-stayed bridge, an extensive array of mechanical strain gage points were installed in sections of the box girders, pylons, and piers. At each instrumented box girder section, five longitudinal gages were plac...

  4. Issues in bridge deck damage evaluation using aerial photos

    Science.gov (United States)

    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.

  5. Super-Light Prefabricated Deck Element Integrated in Traditional Concrete Prefabricated Element Construction

    DEFF Research Database (Denmark)

    Christensen, Jacob Ellehauge; Hertz, Kristian Dahl

    of the super-light slab element are element size, which have greatly reduced the total number of elements the pedestrian bridges consist of. The application also demonstrated the ability to control the path that the forces will take in the element. The deck elements are for example fully prepared......Super-light structures in form of deck elements have been used for the first time in a building to construct indoor pedestrian bridges. Examples of connections to external structures and other super-light deck elements are given along with other details. Other examples on the great versatility...

  6. Rapid replacement of Tangier Island bridges including lightweight and durable fiber-reinforced polymer deck systems.

    Science.gov (United States)

    2009-01-01

    Fiber-reinforced polymer (FRP) composite cellular deck systems were used as new bridge decks on two replacement bridges on Tangier Island, Virginia. The most important characteristics of this application were reduced self-weight and increased durabil...

  7. Hybrid FRP-concrete bridge deck system final report I : development and system performance validation.

    Science.gov (United States)

    2009-10-01

    In this study, the concept of the hybrid FRP-concrete structural systems was applied to both bridge : superstructure and deck systems. Results from the both experimental and computational analysis for : both the hybrid bridge superstructure and deck ...

  8. Towards Sensor-Based Health Monitoring Systems for Bridge Decks: A Full-Depth Precast Deck Panels Case Study

    Directory of Open Access Journals (Sweden)

    Osama Y. Abudayyeh

    2010-01-01

    Full Text Available Traffic and variable loading conditions greatly influence the performance, durability, and safety of a bridge structure throughout its service life. Continuous monitoring can provide the basis for determining the deterioration rate and for estimating the remaining service life, thus assisting in making important decisions regarding bridge maintenance. This paper presents the design and implementation of a health monitoring system for condition assessment of full-depth precast concrete bridge deck, which was developed for the Parkview Bridge in Kalamazoo, Michigan. This system is composed of a remotely accessible on-site data acquisition system and a sensor network of vibrating wire strain gauges to monitor strain and temperature over given time increments. The system relies on the sensor network embedded in the bridge deck to gather static performance data under different loading conditions to provide condition assessment by collecting, storing, analyzing, and reporting relevant performance data over time. The paper presents a practical case study that mainly focuses on describing the initial steps in the development of the sensor network system, namely, the design (system architecture and data structures and construction along with examples of how the data is acquired, organized, presented, and analyzed, keeping in mind that the bridge is still early in its life-cycle and has not yet experienced any structural problems.

  9. Automated GPR Rebar Analysis for Robotic Bridge Deck Evaluation.

    Science.gov (United States)

    Kaur, Parneet; Dana, Kristin J; Romero, Francisco A; Gucunski, Nenad

    2016-10-01

    Ground penetrating radar (GPR) is used to evaluate deterioration of reinforced concrete bridge decks based on measuring signal attenuation from embedded rebar. The existing methods for obtaining deterioration maps from GPR data often require manual interaction and offsite processing. In this paper, a novel algorithm is presented for automated rebar detection and analysis. We test the process with comprehensive measurements obtained using a novel state-of-the-art robotic bridge inspection system equipped with GPR sensors. The algorithm achieves robust performance by integrating machine learning classification using image-based gradient features and robust curve fitting of the rebar hyperbolic signature. The approach avoids edge detection, thresholding, and template matching that require manual tuning and are known to perform poorly in the presence of noise and outliers. The detected hyperbolic signatures of rebars within the bridge deck are used to generate deterioration maps of the bridge deck. The results of the rebar region detector are compared quantitatively with several methods of image-based classification and a significant performance advantage is demonstrated. High rates of accuracy are reported on real data that includes thousands of individual hyperbolic rebar signatures from three real bridge decks.

  10. Quantifying reinforced concrete bridge deck deterioration using ground penetrating radar

    Science.gov (United States)

    Martino, Nicole Marie

    Bridge decks are deteriorating at an alarming rate due to corrosion of the reinforcing steel, requiring billions of dollars to repair and replace them. Furthermore, the techniques used to assess the decks don't provide enough quantitative information. In recent years, ground penetrating radar (GPR) has been used to quantify deterioration by comparing the rebar reflection amplitudes to technologies serving as ground truth, because there is not an available amplitude threshold to distinguish healthy from corroded areas using only GPR. The goal of this research is to understand the relationship between GPR and deck deterioration, and develop a model to determine deterioration quantities with GPR alone. The beginning of this research determines that not only is the relationship between GPR and rebar corrosion stronger than the relationship between GPR and delaminations, but that the two are exceptionally correlated (90.2% and 86.6%). Next, multiple bridge decks were assessed with GPR and half-cell potential (HCP). Statistical parameters like the mean and skewness were computed for the GPR amplitudes of each deck, and coupled with actual corrosion quantities based on the HCP measurements to form a future bridge deck model that can be used to assess any deck with GPR alone. Finally, in order to understand exactly which component of rebar corrosion (rust, cracking or chloride) attenuates the GPR data, computational modeling was carried out to isolate each variable. The results indicate that chloride is the major contributor to the rebar reflection attenuation, and that computational modeling can be used to accurately simulate GPR attenuation due to chloride.

  11. Structural Assessment of Externally Strengthened Bridge Deck Panels

    Science.gov (United States)

    Sim, Jongsung; Oh, Hongseob; Meyer, Christian

    2006-03-01

    Deteriorated concrete bridge decks are strengthened with external bonding technique using either steel plate or various FRPs to enhance the decreased load carrying capacity and serviceability. But the failure characteristics of bridge decks strengthened with various materials can be changed according to mechanical properties of strengthening materials or strengthening scheme as well as the strengthening amount. In this paper, strengthening effect of deck strengthened with carbon fiber sheets, glass fiber sheets or steel plates is compared. And the theoretical load carrying capacity are evaluated using yield line theory and punching shear model properly modified for the strengthened RC member. The panels strengthened with sheet type FRP materials failed more often in a ductile mode, indicating that the failure developed after the rebar yielded.

  12. Design, construction, and field testing of an ultra high performance concrete pi-girder bridge.

    Science.gov (United States)

    2011-01-01

    The Jakway Park Bridge in Buchanan County, Iowa is the first bridge constructed with a new prestesssed girder system composed of : precast Ultra-High Performance Concrete (UHPC). These girders employ an integral deck to facilitate construction and ar...

  13. Experimental studies on multicellular GFRP bridge deck panels ...

    Indian Academy of Sciences (India)

    This paper presents the experimental investigations carried out on hand lay-up prototype multicellular glass fibre reinforced polymer (GFRP) composite bridge deck panels under static and fatigue loading. Various sustainability aspects with regard to GFRP structural members were discussed. The aspects include(i) social ...

  14. PCP cracking and bridge deck reinforcement : an interim report.

    Science.gov (United States)

    2010-10-28

    TxDOT Project 0-6348 Controlling Cracking in Prestressed Concrete Panels and Optimizing Bridge Deck : Reinforcing Steel started on September 1, 2008 and is scheduled to end on August 31, 2012. The project is : proceeding on schedule. This repor...

  15. Silica fume latex modified concrete bridge deck overlay.

    Science.gov (United States)

    1997-12-01

    The Oregon Department of Transportation has used either Silica Fume or Latex Modified Concrete (LMC) to lower chloride permeability in bridge deck overlays. On this project a new project combining both silica fume and LMC was used. The overlay was co...

  16. Ground penetrating radar utilization in exploring inadequate concrete covers in a new bridge deck

    Directory of Open Access Journals (Sweden)

    Md. Istiaque Hasan

    2014-01-01

    Full Text Available The reinforced concrete cast in place four span deck of a concrete bridge near Roanoke, Texas, was recently completed. Due to possible construction errors, it was suspected that the concrete covers in the deck did not conform to drawings and specifications. A full scale non-destructive evaluation of the concrete covers was carried out using ground penetrating radar (GPR equipment. Cover values were determined from the radargram generated from the scan. The estimated covers were plotted on contour maps. Migration data can substitute the drilling based ground truth data without compromising the concrete cover estimations, except for areas with very high cover values. Areas with high water content may result in inaccurate concrete dielectric constants. Based on the results, significant retrofitting of the bridge deck, such as additional overlay, was recommended.

  17. Fatigue crack identification and lifetime prediction for steel bridge deck structures

    NARCIS (Netherlands)

    Pahlavan, P.L.; Pijpers, R.J.M.; Hakkesteegt, H.C.; Jansen, T.H.; Peelen, W.H.A.

    2015-01-01

    Fatigue, as the governing degradation mechanism in steel bridge decks, can lead to non-inspectable cracks under the welded intersections of stiffeners to the deck plate. As a result, estimation of the remaining service life and optimization of the maintenance program of steel bridge decks become a

  18. Determination of brace forces caused by construction loads and wind loads during bridge construction : [summary].

    Science.gov (United States)

    2014-04-01

    Bridges are constructed in stages as pilings, : columns, girders, decks, and other components : are added. At each stage, the structure must be : stable. Girders, which add significant weight to : the developing structure, rest on elastomeric : beari...

  19. Hybrid FRP-concrete bridge deck system final report II : long term performance of hybrid FRP-concrete bridge deck system.

    Science.gov (United States)

    2009-06-01

    This report describes the investigation of the long term structural performance of a : hybrid FRP-concrete (HFRPC) bridge deck on steel girders. The study aimed at : assessing three long term aspects pertaining to the HFRPC bridge deck: (1) creep : c...

  20. Longitudinal cracking in concrete at bridge deck dams on structural rehabilitation projects.

    Science.gov (United States)

    2012-10-01

    The main objective of this project was to identify the causes of longitudinal cracking in newly placed concrete deck segments adjacent to : bridge deck expansion dam rehabilitations within District 3-0 of the Pennsylvania Department of Transportation...

  1. Skew decks in reinforced concrete bridges

    Directory of Open Access Journals (Sweden)

    B. F. ROCHA

    Full Text Available Abstract This research investigates reinforced concrete plates and shells with skew reinforcement whose directions are not aligned with the principal internal forces. Two normal forces, one tangential force, two bending moments, and one twisting moment are defined in the plane of the element. The analysis includes two shear forces in the transverse direction. The membrane and flexural forces are distributed between two panels at the upper and lower faces of the element. The smeared cracking model, equilibrium considerations, and plasticity approach yield the design equations of the skew reinforcement. The slab reinforcement of flat bridges, with and without lateral beams and girder bridges are compared considering different skew angles. The minimum reinforcement criteria of skew meshes are discussed. The results show that skew reinforcement yields higher steel and concrete stresses.

  2. Evaluation of bridge decks on Route I-64 at Hampton, Virginia.

    Science.gov (United States)

    1975-01-01

    The testing of 15 bridges on Route I-64 just west of the Hampton Roads Bridge Tunnel marked the first major use of electrical potential readings and chloride analyses in evaluating the condition of bridge decks in Virginia. Two of the decks were also...

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

    Science.gov (United States)

    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.

  4. Structural condition assessment and service load performance of deteriorated prestressed concrete deck beam bridges

    Science.gov (United States)

    Fuentes, Juan Bolivar

    Precast pretensioned deck beam bridges are a generic bridge type widely used by IDOT for new construction through the end of the 1970's and still widely used on county roads throughout Illinois. While these bridges were economical to build, IDOT discontinued their use because reflective cracks developed along the length of the longitudinal joints between beams. Three 30 years old deteriorated beams were removed from an existing bridge over Spoon River in Fulton County, IL and delivered to Newmark Civil Engineering Laboratory. The program consisted of a series of comprehensive, destructive and non-destructive, tests and evaluations of the three beams with emphasis on three major areas; (1) The Condition Assessment of the as-delivered beams. (2) The service load performance of the bridge sub-assemblage constructed from those beams. After a comprehensive inspection of the beams was completed, the beams were integrated together into a bridge subassembly that simulated a bridge lane. (3) Following the service load tests, the three beams were separated and tested individually to failure. The critical signs to be observed in existing structures that will lead the inspectors to conclude that a deck beam is being overloaded were are also studied. Several conclusions were found. Cracking of the longitudinal joint has little effect on the stiffness of the bridge if the transverse rod is snug. The presence of a snug transverse tie rod increases the strength of the longitudinal joint. After a longitudinal joint has fractured, reincorporating a snug transverse rod can significantly reestablish the stiffness of the longitudinal joint and reduce overloading of a deteriorated beam. Participation factors must be based on relative bending moments of one beam with respect to the total amount of bending moment produced by the applied load and not to the amount of total vertical displacement. The participation factors will vary along the span of the bridge deck and will depend on the

  5. Development and validation of deterioration models for concrete bridge decks - phase 1 : artificial intelligence models and bridge management system.

    Science.gov (United States)

    2013-06-01

    This research documents the development and evaluation of artificial neural network (ANN) models to predict the condition ratings of concrete highway bridge decks in Michigan. Historical condition assessments chronicled in the national bridge invento...

  6. Abrasion-resistant concrete mix designs for precast bridge deck panels.

    Science.gov (United States)

    2010-08-01

    The report documents laboratory investigations undertaken to develop high performance concrete (HPC) for precast and pre-stressed bridge deck components that would reduce the life-cycle cost of bridges by improving the studded tire wear (abrasion) re...

  7. High skew link slab bridge system with deck sliding over backwall or backwall sliding over abutments : part II.

    Science.gov (United States)

    2011-09-30

    A new bridge design and construction trend to help improve durability and rideability is to remove expansion joints over piers and abutments. One approach to achieve this is to make the deck continuous over the piers by means of a link slab while the...

  8. High skew link slab bridge system with deck sliding over backwall or backwall sliding over abutments : part I.

    Science.gov (United States)

    2011-09-30

    A new bridge design and construction trend to help improve durability and rideability is to remove expansion : joints over piers and abutments. One approach to achieve this is to make the deck continuous over the piers by : means of a link slab while...

  9. Phenomenology study of HERMES ground-penetrating radar technology for detection and identification of common bridge deck features

    Science.gov (United States)

    2001-06-01

    Accurately evaluating the condition of a bridge deck over time and using this information to choose appropriate maintenance techniques has become critical for the efficient allocation of resources to bridge deck maintenance. Tomographic imaging of su...

  10. The Economic Impact of Implementing Nondestructive Testing of Reinforced Concrete Bridge Decks in Indiana

    OpenAIRE

    Taylor, Benjamin R; Qiao, Yu; Bowman, Mark D; Labi, Samuel

    2016-01-01

    The deck is among the most expensive components of a bridge over its lifetime because of the frequent and costly maintenance and rehabilitation required. Currently, the Indiana Department of Transportation (INDOT) performs visual inspections of a bridge deck as the principal means of determining its condition, which enables the inspector to definitively document the surface condition while the unseen condition below the deck surface is left to the inspector’s expert judgement. To compensate f...

  11. A review on the suitability of rubberized concrete for concrete bridge decks

    Science.gov (United States)

    Syamir Senin, Mohamad; Shahidan, Shahiron; Radziah Abdullah, Siti; Anting Guntor, Nickholas; Syazani Leman, Alif

    2017-11-01

    Road authorities manage a large population of ageing bridges, a substantial number of which fail to meet the current requirements either due to deterioration and other structural deficiencies or as a result of the escalating demands imposed by increased traffic. This problem is related to the dynamic load from vehicles. This problem can be solved by producing a type of concrete that can reduce the amplitude of oscillation or vibration such as rubberized concrete. Green construction has been a very important aspect in concrete production field in the last decade. One of the most problematic waste materials is scrap tires. The use of scrap tires in civil engineering is increasing by producing rubberized concrete. Rubberized concrete is a type of concrete that is mixed with rubber. The purpose of this review is to justify the suitability of rubberized concrete for concrete bridge decks. Several parameters named physical, chemical and mechanical properties were measured to ensure the suitability of rubberized concrete for concrete bridge decks. Rubberized concrete has similar workability to normal concrete. The rubber reduced the density and compressive strength of the concrete while increased the flexural strength, water absorption and damping ratio. The used of rubber in concrete beyond 20% is not recommended due to decreasing in compressive strength. Rubberized concrete recommended to be used in circumstances where vibration damping was required such as in bridge construction as shock-wave absorber.

  12. Development of precast bridge deck overhang system : technical report.

    Science.gov (United States)

    2011-07-01

    The implementation of full-depth, precast overhang panel systems has the potential to improve constructability, : productivity, and make bridges more economical. Initial testing and analyses reported in the 0-6100-2 report resulted in : a design that...

  13. Arch-Axis Coefficient Optimization of Long-Span Deck-Type Concrete-Filled Steel Tubular Arch Bridge

    Science.gov (United States)

    Liu, Q. J.; Wan, S.; Liu, H. C.

    2017-11-01

    This paper is based on Nanpuxi super major bridge which is under construction and starts from Wencheng Zhejiang province to Taishun highway. A finite element model of the whole bridge is constructed using Midas Civil finite element software. The most adverse load combination in the specification is taken into consideration to determine the method of calculating the arch-axis coefficient of long-span deck-type concrete-filled steel tubular arch bridge. By doing this, this paper aims at providing references for similar engineering projects.

  14. Estimation of Structure-Borne Noise Reduction Effect of Steel Railway Bridge Equipped with Floating Ladder Track and Floating Reinforced-Concrete Deck

    Science.gov (United States)

    Watanabe, Tsutomu; Sogabe, Masamichi; Asanuma, Kiyoshi; Wakui, Hajime

    A number of steel railway bridges have been constructed in Japan. Thin steel members used for the bridges easily tend to vibrate and generate structure-borne noise. Accordingly, the number of constructions of steel railway bridges tends to decrease in the urban areas from a viewpoint of environmental preservation. Then, as a countermeasure against structure-borne noise generated from steel railway bridges, we have developed a new type of the steel railway bridge equipped with a floating-ladder track and a floating reinforced-concrete (RC) deck. As a result of train-running experiment, it became apparent that the new steel railway bridge installed by double floating system has reduced a vibration velocity level by 10.5 dB(A) at main girder web as compared with a steel railway bridge installed by directly fastened track. This reduction effect was achieved by the ladder track and RC deck supported by resilient materials.

  15. A Finite Element Model for the Analysis of Bridge Decks | Onyia ...

    African Journals Online (AJOL)

    However, the method is limited to only simply supported decks. Also, reading the charts and interpolating between curves can be very tiresome and can easily introduce errors in the analysis. This paper therefore proposes and develops a finite element model as a more versatile alternative for the analysis of bridge decks for ...

  16. State-of-the-art report on rapid repair techniques for bridge decks.

    Science.gov (United States)

    1990-01-01

    Bridges that are candidates for rapid repair techniques have peak-hour traffic volumes that are so high that it is not practical to close a lane to repair the deck or to install a deck protection system except during off-peak traffic periods. This re...

  17. Structural design guidelines for concrete bridge decks reinforced with corrosion-resistant reinforcing bars.

    Science.gov (United States)

    2014-10-01

    This research program develops and validates structural design guidelines and details for concrete bridge decks with : corrosion-resistant reinforcing (CRR) bars. A two-phase experimental program was conducted where a control test set consistent : wi...

  18. Evaluation of bent caps in reinforced concrete deck girder bridges : part 2.

    Science.gov (United States)

    2008-09-01

    This report describes research conducted to enable evaluation of existing vintage bent cap beams in reinforced concrete : deck girder bridges. The report is organized into two parts: 1) flexural anchorage capacity response and prediction of : reduced...

  19. Evaluation of bent caps in reinforced concrete deck girder bridges : part 1.

    Science.gov (United States)

    2008-09-01

    This report describes research conducted to enable evaluation of existing vintage bent cap beams in reinforced concrete : deck girder bridges. The report is organized into two parts: 1) flexural anchorage capacity response and prediction of : reduced...

  20. Impact of overweight vehicles (with heavy axle loads) on bridge deck deterioration.

    Science.gov (United States)

    2012-03-01

    Bridge deck slabs develop compressive stresses from global flexural deformation and locally from high-level : wheel loads when it is subjected to overweight trucks. This study quantified the impact of overweight vehicles : with heavy axle loads on br...

  1. Corrosion protection service life of epoxy-coated reinforcing steel in Virginia bridge decks.

    Science.gov (United States)

    2003-01-01

    The corrosion protection service life extension provided by epoxy-coated reinforcement (ECR) was determined by comparing ECR and bare steel bars from 10 Virginia bridge decks built between 1981 and 1995. The objective was to determine the corrosion p...

  2. Influence of fly ash, slag cement and specimen curing on shrinkage of bridge deck concrete.

    Science.gov (United States)

    2014-12-01

    Cracks occur in bridge decks due to restrained shrinkage of concrete materials. Concrete materials shrink as : cementitious materials hydrate and as water that is not chemically bonded to cementitious materials : migrates from the high humid environm...

  3. Health monitoring of precast bridge deck panels reinforced with glass fiber reinforced polymer (GFRP) bars.

    Science.gov (United States)

    2012-03-01

    The present research project investigates monitoring concrete precast panels for bridge decks that are reinforced with Glass Fiber Reinforced Polymer (GFRP) bars. Due to the lack of long term research on concrete members reinforced with GFRP bars, lo...

  4. Creation of an ODOT specification for patching or overlay of bridge decks.

    Science.gov (United States)

    2009-09-01

    Bridge deck cracking is a huge problem in the United States, and various agencies have sponsored research endeavoring to determine the underlying problems. A number of causes have been identified, including thermal movement, plastic shrinkage, and ea...

  5. Light-weight aluminium bridges and bridge decks. An overview of recent applications

    NARCIS (Netherlands)

    Maljaars, J.; Soetens, F.; Kluyver, D. de

    2008-01-01

    The last decades have shown a large increase in the application of aluminium alloys for light-weight bridges. For bridge construction, aluminium alloys have some specific advantages, but also some points of attention. This paper deals with some recent projects of aluminium bridges, and for these

  6. Reinforced Concrete Bridge Deck Condition Assessment Methods Using Ground Penetrating Radar and Infrared Thermography

    OpenAIRE

    Nicole M. Martino

    2017-01-01

    Reinforced concrete bridge deck condition assessments primarily use visual inspection methods, where an inspector looks for and records locations of cracks, potholes, efflorescence and other signs of probable deterioration. Sounding is another technique used to diagnose the condition of a bridge deck, however this method listens for damage within the subsurface as the surface is struck with a hammer or chain. Even though extensive procedures are in place for using these inspection techniques,...

  7. Analysis, prediction, and case studies of early-age cracking in bridge decks

    Science.gov (United States)

    ElSafty, Adel; Graeff, Matthew K.; El-Gharib, Georges; Abdel-Mohti, Ahmed; Mike Jackson, N.

    2016-06-01

    Early-age cracking can adversely affect strength, serviceability, and durability of concrete bridge decks. Early age is defined as the period after final setting, during which concrete properties change rapidly. Many factors can cause early-age bridge deck cracking including temperature change, hydration, plastic shrinkage, autogenous shrinkage, and drying shrinkage. The cracking may also increase the effect of freeze and thaw cycles and may lead to corrosion of reinforcement. This research paper presents an analysis of causes and factors affecting early-age cracking. It also provides a tool developed to predict the likelihood and initiation of early-age cracking of concrete bridge decks. Understanding the concrete properties is essential so that the developed tool can accurately model the mechanisms contributing to the cracking of concrete bridge decks. The user interface of the implemented computer Excel program enables the user to input the properties of the concrete being monitored. The research study and the developed spreadsheet were used to comprehensively investigate the issue of concrete deck cracking. The spreadsheet is designed to be a user-friendly calculation tool for concrete mixture proportioning, temperature prediction, thermal analysis, and tensile cracking prediction. The study also provides review and makes recommendations on the deck cracking based mainly on the Florida Department of Transportation specifications and Structures Design Guidelines, and Bridge Design Manuals of other states. The results were also compared with that of other commercially available software programs that predict early-age cracking in concrete slabs, concrete pavement, and reinforced concrete bridge decks. The outcome of this study can identify a set of recommendations to limit the deck cracking problem and maintain a longer service life of bridges.

  8. The influence of deck flexibility on the dynamic response of road bridges

    Directory of Open Access Journals (Sweden)

    E. P. SCHMIDT

    Full Text Available ABSTRACT A simplified methodology is proposed for the dynamic analysis of curved road bridges under the effect of a 3C class heavy vehicle. The dynamic models of both vehicle and bridge are considered to be uncoupled, being bound by the interaction forces. These forces come from the vehicle dynamic analysis, initially under rigid deck, subjected to a support excitation caused by the pavement geometric irregularities. Such forces are statically condensed in the vehicle centre of mass and applied to a simplified structural model (‘unifilar’ of a curved bridge with box girder section, considering the bridge super elevation. The influence of the rigid deck hypothesis on the dynamic response is assessed by an iterative procedure, in which the deck displacements are added to the pavement irregularities, to obtain an “equivalent irregularity” function. The new interaction forces are re-applied to the bridge model to determine new displacements, repeating the procedure until the results converge.

  9. M324 : investigation of closure pour elimination for phased construction of steel girder bridges.

    Science.gov (United States)

    2014-10-01

    Phased construction is a common practice used by State DOTs during the : replacement of a bridge. This method allows for the traffic flow to be maintained on half : of the bridge while a new deck is constructed on the other half. For steel girder bri...

  10. Plans for crash-tested wood bridge railings for concrete decks

    Science.gov (United States)

    Michael A. Ritter; Ronald K. Faller; Barry T. Rosson; Paula D. Hilbrich Lee; Sheila Rimal. Duwadi

    1998-01-01

    As part of a continuing cooperative research between the Midwest Roadside Safety Facility (MwRSF); the USDA Forest Service, Forest Products Laboratory (FPL); and the Federal Highway Administration (FHWA), several crashworthy wood bridge railings and approach railing transitions have been adapted for use on concrete bridge decks. These railings meet testing and...

  11. Measurement of bridge deck layout prior to concrete placement : final report.

    Science.gov (United States)

    2017-01-01

    The main objective of this research was to develop a method of measuring and : producing as built bridge drawings. This was the first step in the feasibility : assessment for automated bridge deck paving. The research goes to show the : standard meth...

  12. Flow field analysis of a pentagonal-shaped bridge deck by unsteady RANS

    Directory of Open Access Journals (Sweden)

    Md. Naimul Haque

    2016-01-01

    Full Text Available Long-span cable-stayed bridges are susceptible to dynamic wind effects due to their inherent flexibility. The fluid flow around the bridge deck should be well understood for the efficient design of an aerodynamically stable long-span bridge system. In this work, the aerodynamic features of a pentagonal-shaped bridge deck are explored numerically. The analytical results are compared with past experimental work to assess the capability of two-dimensional unsteady RANS simulation for predicting the aerodynamic features of this type of deck. The influence of the bottom plate slope on aerodynamic response and flow features was investigated. By varying the Reynolds number (2 × 104 to 20 × 104 the aerodynamic behavior at high wind speeds is clarified.

  13. Evaluation of bridge decks using non-destructive evaluation (NDE) at near highway speeds for effective asset management.

    Science.gov (United States)

    2015-06-01

    Remote sensing technologies allow for the condition evaluation of bridge decks at near highway speed. : Data collection at near highway speed for assessment of the top of the concrete deck and proof of : concept testing for the underside of the deck ...

  14. Using artificial neural networks in the design of orthotropic bridge decks

    Directory of Open Access Journals (Sweden)

    Ahmed Shamel Fahmy

    2016-12-01

    Full Text Available For orthotropic bridge decks a lot of progress has been made in the development of codes to aid in the design process, in addition to software tools for numerical analysis and design. However, professional software tools will not aid the designer in choosing a preliminary economic layout at the conceptual design stage. Designers would go through iterative, lengthy and expensive procedures to reach the best configuration. The present research provides a methodology to investigate the contingency of using artificial neural networks for conceptual design of orthotropic steel-deck bridge. A neural network model was trained with different combinations of dimensions, and eight types of safety checks were performed on all of them. The resulting network can predict whether the deck is safe or not. It is found that this approach for the selection of orthotropic deck dimensions is a better and cost-effective option compared with international codes or expert opinion.

  15. The Impact of Traffic-Induced Bridge Vibration on Rapid Repairing High-Performance Concrete for Bridge Deck Pavement Repairs

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2014-01-01

    Full Text Available Based on forced vibration tests for high-performance concrete (HPC, the influence of bridge vibration induced by traveling vehicle on compressive strength and durability of HPC has been studied. It is concluded that 1 d and 2 d compressive strength of HPC decreased significantly, and the maximum reduction rate is 9.1%, while 28 d compressive strength of HPC had a slight lower with a 3% maximal drop under the action of two simple harmonic vibrations with 2 Hz, 3 mm amplitude, and 4 Hz, 3 mm amplitude. Moreover, the vibration had a slight effect on the compressive strength of HPC when the simple harmonic vibration had 4 Hz and 1 mm amplitude; it is indicated that the amplitude exerts a more prominent influence on the earlier compressive strength with the comparison of the frequency. In addition, the impact of simple harmonic vibration on durability of HPC can be ignored; this shows the self-healing function of concrete resulting from later hydration reaction. Thus, the research achievements mentioned above can contribute to learning the laws by which bridge vibration affects the properties of concrete and provide technical support for the design and construction of the bridge deck pavement maintenance.

  16. Fatigue analysis and life prediction of composite highway bridge decks under traffic loading

    Directory of Open Access Journals (Sweden)

    Fernando N. Leitão

    Full Text Available Steel and composite (steel-concrete highway bridges are currently subjected to dynamic actions of variable magnitude due to convoy of vehicles crossing on the deck pavement. These dynamic actions can generate the nucleation of fractures or even their propagation on the bridge deck structure. Proper consideration of all of the aspects mentioned pointed our team to develop an analysis methodology with emphasis to evaluate the stresses through a dynamic analysis of highway bridge decks including the action of vehicles. The design codes recommend the application of the curves S-N associated to the Miner's damage rule to evaluate the fatigue and service life of steel and composite (steel-concrete bridges. In this work, the developed computational model adopted the usual mesh refinement techniques present in finite element method simulations implemented in the ANSYS program. The investigated highway bridge is constituted by four longitudinal composite girders and a concrete deck, spanning 40.0m by 13.5m. The analysis methodology and procedures presented in the design codes were applied to evaluate the fatigue of the bridge determining the service life of the structure. The main conclusions of this investigation focused on alerting structural engineers to the possible distortions, associated to the steel and composite bridge's service life when subjected to vehicle's dynamic actions.

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

    Science.gov (United States)

    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.

  18. Rational load rating of deck-girder bridges with girder end shear cracks in reverse orientation : technical summary.

    Science.gov (United States)

    2017-04-01

    A user interface creates a grillage model of an existing bridge and places various rating trucks on the : bridge. Equivalent flexibility analysis distributes truck live loads within deck panels to surrounding : girders and diaphragms. Stiffness matri...

  19. Cost effective bridge deck reconstruction in Kansas using high-density concrete overlays and asphalt membrane overlays : final report.

    Science.gov (United States)

    2009-08-01

    In 1976 the Federal Highway Administration (FHWA) approved federal aid funding for experimental : installations of corrosion protection for reinforcing steel in existing concrete bridge decks. Sixteen of the sixty-nine : Kansas bridges with Cost Effe...

  20. Cost effective bridge deck reconstruction in Kansas using high-density concrete overlays and asphalt membrane overlays : summary.

    Science.gov (United States)

    2009-08-01

    In 1976 the Federal Highway Administration (FHWA) approved federal aid funding for experimental installations of corrosion protection for reinforcing steel in existing concrete bridge decks. Sixteen of the sixty-nine Kansas bridges with Cost Effectiv...

  1. Bridge Deck Runoff: Water Quality Analysis and BMP Effectiveness

    Science.gov (United States)

    2010-12-01

    The Alaska Department of Transportation (ADOT) is responsible for more than 700 bridges - most span water bodies. Are these water bodies affected by stormwater runoff from ADOT bridges? What are the regulatory and economic constraints on the ADOT reg...

  2. Experimental Analysis of Stiffness of the Riveted Steel Railway Bridge Deck Members’ Joints

    Directory of Open Access Journals (Sweden)

    Gocál Jozef

    2014-12-01

    Full Text Available 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.

  3. Faster bridge construction using precast substructures : brief.

    Science.gov (United States)

    2011-07-01

    Bridge replacement often requires road closures and detours that frustrate road users. It remains a key goal of Wisconsin DOT to reduce construction-related road use interruptions. This will be a challenge with bridges: Bridge inspections in 2007 ide...

  4. Fatigue crack sizing in steel bridge decks using ultrasonic guided waves

    NARCIS (Netherlands)

    Pahlavan, P.L.; Blacquière, G.

    2016-01-01

    A baseline-free quantitative sizing methodology utilizing ultrasonic guided waves for fatigue cracks under welded stiffeners in steel bridge decks has been developed. An inverse wavefield extrapolation based formulation for obtaining the crack reflectivity and depth profile has been presented in the

  5. Evaluation of performance and maximum length of continuous decks in bridges : part 1.

    Science.gov (United States)

    2011-06-01

    The purpose of this research was to evaluate the performance history of continuous bridge decks in the State of Georgia, to determine why the current design detail works, to recommend a new design detail, and to recommend the maximum and/or optimum l...

  6. Evaluation of the SafeLane overlay system for crash reduction on bridge deck surfaces.

    Science.gov (United States)

    2010-03-01

    The winter performance of the SafeLane commercial overlay system has been evaluated at four installations on : bridge decks in the state of Minnesota. The study was conducted over a period of a total of three years. Analyses : included mechanical ...

  7. MEASURED AND CALCULATED DYNAMIC PROPERTIES OF THE BRIDGE DECK MODEL REINFORCED WITH FRP BARS

    Directory of Open Access Journals (Sweden)

    Grzegorz PIĄTKOWSKI

    Full Text Available Composite materials mainly used in the aeronautics industry are gaining more and more application in various areas such as the construction of bridges. The article presents a set of dynamic researches carried out on a plate made of lightweight concrete reinforced with composite bars. The tested plate with dimensions 514 x 190 x 18 cm was a model of the real bridge deck. A multi-channel signal recorder with specialized software was used for performing the measurements and to estimate modal parameters of the plate. Dynamic response of the plate on a modal hammer impact was measured with numerous of piezoelectric acceleration sensors. The vibration tests were carried out simultaneously with statics tests only for non-cracked concrete of the plate. A range of FEM models was created, started with analytical 1-D beam model. Next, more complex 2-D plate and 3-D volume models were developed. The aim was to show how the results change in terms of complexity of the model. Only in the 3-D model the composite rebar was modelled. Additionally, in case of 2-D and 3-D models there were considered various lengths of the selected support. The basic frequencies and mode shapes obtained for physical model were compared with those for numerical models. There were significant differences. The conducted analysis indicated more complicated than theoretical boundary conditions of the tested plate.

  8. The Dynamic Properties of the Bridge Deck Model Reinforced With FRP Bars

    Directory of Open Access Journals (Sweden)

    Markiewicz Barbara

    2015-01-01

    Full Text Available Significant application of composites can be observed in numerous fields over the last decades. Composite materials mainly used in the aeronautics industry are gaining more and more application in various areas such as the construction of bridges. The article presents a set of dynamic research carried out on a plate made of lightweight concrete reinforced with composite rods. The tested plate with dimensions 514 × 190 × 18 cm was a model of the actual bridge deck. A multi-channel signal recorder with specialized software was used for performing the measurements and estimating modal parameters of the plate. Dynamic response of the plate on a modal hammer impact was measured with numerous of piezoelectric acceleration sensors. A range of FEM models was created, started with 1-D beam model. Next, 2-D plate and 3-D volume, more complex models were developed. Only in the 3-D model the composite rods were modeled. The basic frequencies and mode shapes obtained for physical model were compared with those for numerical models. There were significant differences. The conducted analysis indicated more complicated than theoretical boundary conditions of the tested plate.

  9. Full-scale observation of the flow downstream of a suspension bridge deck

    DEFF Research Database (Denmark)

    Cheynet, Etienne; Jakobsen, Jasna Bogunović; Snæbjörnsson, Jónas

    2017-01-01

    The paper presents a full-scale observation of the flow conditions downstream of a suspension bridge by a system of synchronized short-range dual-Doppler wind lidars. The lidar units were deployed directly on the bridge walkway during a four-day pilot experiment. The wind velocity was monitored...... at every meter along a 111 m long vertical line segment 40 m downstream of the deck, with a sampling period of one second. The lidar wind data are studied in terms of the mean wind velocity deficit and turbulence intensity downstream of the bridge deck. They provided a full-scale characterization...... tests. Challenges in the estimation of the wind velocity data related to the variable measurement noise of the individual lidars, as a function of the wind direction, are highlighted. Suggestions for future applications of a similar measurement set-up, based on this unique study performed during...

  10. Evaluating Louisiana new deck continuity detail for precast prestressed concrete girder bridges : research project capsule.

    Science.gov (United States)

    2014-08-01

    The goal of everyone in the transportation community is to build bridges : that are economic, easy to construct, and durable. Therefore, accelerating : bridge construction through the use of precast concrete or prefabricated : steel girders is a comm...

  11. Super-long bridges with floating towers: the role of multi-box decks and Hardware-In-the-Loop technology for wind tunnel tests

    Science.gov (United States)

    Zasso, A.; Argentini, T.; Bayati, I.; Belloli, M.; Rocchi, D.

    2017-12-01

    The super long fjord crossings in E39 Norwegian project pose new challenges to long span bridge design and construction technology. Proposed solutions should consider the adoption of bridge deck with super long spans or floating solutions for at least one of the towers, due to the relevant fjord depth. At the same time, the exposed fjord environment, possibly facing the open ocean, calls for higher aerodynamic stability performances. In relation to this scenario, the present paper addresses two topics: 1) the aerodynamic advantages of multi-box deck sections in terms of aeroelastic stability, and 2) an experimental setup in a wind tunnel able to simulate the aeroelastic bridge response including the wave forcing on the floating.

  12. Live load test and failure analysis for the steel deck truss bridge over the New River in Virginia.

    Science.gov (United States)

    2009-01-01

    This report presents the methods used to model a steel deck truss bridge over the New River in Hillsville, Virginia. These methods were evaluated by comparing analytical results with data recorded from 14 members during live load testing. The researc...

  13. Evaluation of bridge decks using non-destructive evaluation (NDE) at near highway speeds for effective asset management - pilot project.

    Science.gov (United States)

    2016-09-29

    This project piloted the findings from an initial research and development project pertaining to the detection, : quantification, and visualization of bridge deck distresses through the use of remote sensing techniques, specifically : combining optic...

  14. Development of high-performance concrete mixtures for durable bridge decks in Montana using locally available materials.

    Science.gov (United States)

    2005-03-01

    "The Montana Department of Transportation (MDT) is performing research to develop a cost-effective, indigenous highperformance : concrete (HPC) for use in bridge deck applications. The investigation was divided into two tasks: 1) : identification of ...

  15. Development and validation of deterioration models for concrete bridge decks - phase 2 : mechanics-based degradation models.

    Science.gov (United States)

    2013-06-01

    This report summarizes a research project aimed at developing degradation models for bridge decks in the state of Michigan based on durability mechanics. A probabilistic framework to implement local-level mechanistic-based models for predicting the c...

  16. The Effect of Deck Width Addition Toward Stability of Cable Stayed Bridge: Case Study of Siak Sri Indrapura Bridge, Riau

    Directory of Open Access Journals (Sweden)

    Supriyadi Bambang

    2017-01-01

    Full Text Available An aeroelastic interaction always take places in long-span bridge, i.e. the dynamic relationship between wind forces (aerodynamic and bridge structural motion (dynamics. Wind forces may lead to serviceability and safety problems, and may even cause instability of the whole bridge structure due to the flexibility nature of long span bridge structures.The slimer girder plate will make the structure more unstable as can be seen from the occurrence of lateral deformation. This paper presents the results analysis of cable stayed bridge that has total span of 640 m, two planes configuration of harp-typed hanger cable, the A shape pylons span along 320 m (main span,and side span of 160m. Structural analysis was conducted to determine the optimum ratio between width and spans of cable stayed bridge. The bridge was modeled with various width of 7 to 22 m. Structural modelling was conducted using SAP2000 software to analyze the structural stability of cable stayed bridge under wind load at speed of 35 m/s.The influence of wind loads to the cable stayed bridge stability can be seen based on the bridge deck deformation at the Y-axis (U2, in which for the width of the bridge deck of 7 m, 8 m, 9 m and 10 m, the deformation of U2 are 0.26 m; 0.17 m; 0.12 m and 0.10 m, respectively. Meanwhile, for bridge’s width of 11-22 m, the value of U2 axis deformation is relatively constant between 0.08 m to 0.07 m. This finding suggests that the ratio between width and length of bridge greatly affect the stability of the cable stayed bridge. Cable-stayed bridge, especially for concrete bridge, with two plain system having optimum ratio of width and length show no sign of an aerodynamic instability when fulfills the requirements of B ≥ L / 3.

  17. Assessment of concrete bridge decks with alkali silica reactions

    DEFF Research Database (Denmark)

    Eriksen, Kirsten; Jansson, Jacob; Geiker, Mette Rica

    2008-01-01

    , Bagsværd, Denmark to provide information on the damage condition as well as the residual reactivity of the concrete. The Danish Road Directory’s guidelines for inspection and assessment of alkali silica damaged bridges will be briefly presented, and proposed modifications will be describe...

  18. Modelling and fatigue life assessment of orthotropic bridge deck details using FEM

    Czech Academy of Sciences Publication Activity Database

    Aygül, M.; AL-Emrani, M.; Urushadze, Shota

    2012-01-01

    Roč. 40, July (2012), s. 129-142 ISSN 0142-1123 R&D Projects: GA MŠk(CZ) 7E08098 Grant - others:evropská komise(XE) RFSR-CT-2008-00033 (BRIFAG) Institutional support: RVO:68378297 Keywords : orthotropic bridge deck * open ribs * structural hot spot stress * effective notch stress Subject RIV: JM - Building Engineering Impact factor: 1.976, year: 2012

  19. Performance of streamlined bridge decks in relation to the aerodynamics of a flat plate

    DEFF Research Database (Denmark)

    Larose, Guy; Livesey, Flora M.

    1997-01-01

    The aerodynamics of three modern bridge decks are compared to the aerodynamics of a 16:1 flat plate. The comparisons are made on the basis of the analytical evaluation of the performance of each cross-section to the buffeting action of the wind. In general, the closed-box girders studied...... in this paper showed buffeting responses similar to a flat plate with the exception of the multi-box girder which performed much better aerodynamically....

  20. Comparison between major repair and replacement options for a bridge deck life cycle assessment: A case study

    Directory of Open Access Journals (Sweden)

    Abu Dabous Saleh

    2017-01-01

    Full Text Available Material production, manufacturing, transportation, usage, and end of lifeprocessing are usually the main contributors defining the life cycle assessment (LCA. Bridge infrastructure is important to the economy and the society. Over their life cycle, highway bridges experience several stressors that can significantly affect their structural performance and therefore require rehabilitation. This paper discusses the life cycle analysis of bridge rehabilitation decisions and demonstrates the analysis with a case study of a bridge located in Ontario, Canada. The LCA of the bridge deck is analyzed for two rehabilitation strategies: major repair and replacement. The study focuses on evaluating the different life cycle phases of the bridge deck by assessing their carbon dioxide emission, energy consumption and cost. Also, the paper presents the impact of the different elements within each phase to identify the most contributing elements. The LCA of the bridge deck is analyzed and estimated with the aid of CES EduPack 2016 software that includes a database of more than 4000 different materials and more than 200 manufacturing processes. Analysis of the case study shows that material phase causes significant life cycle impact. The study concluded that the deck replacement yields higher environmental impact and life cycle cost compared to repairing and strengthening the deck.

  1. Phase and widening construction of steel bridges.

    Science.gov (United States)

    2014-03-01

    Phase construction is used to maintain traffic without interruption and generally refers to sequenced construction where a portion of the bridge is under construction while the remainder continues to carry traffic. The method typically results in two...

  2. Characterization of Stormwater Runoff From Bridge Decks in Eastern Massachusetts, 2014–16

    Science.gov (United States)

    Smith, Kirk P.; Sorenson, Jason R.; Granato, Gregory E.

    2018-05-02

    The quality of stormwater runoff from bridge decks (hereafter referred to as “bridge-deck runoff”) was characterized in a field study from August 2014 through August 2016 in which concentrations of suspended sediment (SS) and total nutrients were monitored. These new data were collected to supplement existing highway-runoff data collected in Massachusetts which were deficient in bridge-deck runoff concentration data. Monitoring stations were installed at three bridges maintained by the Massachusetts Department of Transportation in eastern Massachusetts (State Route 2A in the city of Boston, Interstate 90 in the town of Weston, and State Route 20 near Quinsigamond Village in the city of Worcester). The bridges had annual average daily traffic volumes from 21,200 to 124,000 vehicles per day; the land use surrounding the monitoring stations was 25 to 67 percent impervious.Automatic-monitoring techniques were used to collect more than 160 flow-proportional composite samples of bridge-deck runoff. Samples were analyzed for concentrations of SS, loss on ignition of suspended solids (LOI), particulate carbon (PC), total phosphorus (TP), total dissolved nitrogen (DN), and particulate nitrogen (PN). The distribution of particle size of SS also was determined for composite samples. Samples of bridge-deck runoff were collected year round during rain, mixed precipitation, and snowmelt runoff and with different dry antecedent periods throughout the 2-year sampling period.At the three bridge-deck-monitoring stations, median concentrations of SS in composite samples of bridge-deck runoff ranged from 1,490 to 2,020 milligrams per liter (mg/L); however, the range of SS in individual composites was vast at 44 to 142,000 mg/L. Median concentrations of SS were similar in composite samples collected from the State Route 2A and Interstate 90 bridge (2,010 and 2,020 mg/L, respectively), and lowest at the State Route 20 bridge (1,490 mg/L). Concentrations of coarse sediment (greater

  3. Long term striping alternatives for bridge decks : executive summary report.

    Science.gov (United States)

    2009-01-01

    ODOT uses a number of pavement marking : materials including waterborne and alkyd traffic paint, : polyester, thermoplastic, preformed tapes, epoxy, and : heat-fused preformed thermoplastic; which are : addressed in ODOT Construction and Material : S...

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

    Science.gov (United States)

    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

  5. Flexible concrete link slabs used as expansion joints in bridge decks

    DEFF Research Database (Denmark)

    Lárusson, Lárus Helgi; Fischer, Gregor

    2011-01-01

    reinforcement serves as a flexible concrete element between the adjacent deck segments. The use of an Engineered Cementitious Composite (ECC) material instead of conventional concrete significantly reduces crack widths under service conditions and prevents deterioration of the link slab in the tension......Deterioration of bridge structures with mechanical expansion joints between simply supported spans can cause repeated maintenance needs and high repair costs. Damage occurs due to accumulation of debris within the expansion joint, corrosion of deck reinforcement, spalling of concrete, leakage...... of water through the expansion joint and subsequent corrosion of girders and girder bearings. Investigations on joint-less superstructures using conventional steel reinforcement in so-called concrete link slabs indicate improved performance and economic feasibility. However, this concept requires...

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

    Science.gov (United States)

    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.

  7. Compilation of accelerated bridge construction (ABC) bridges : final report.

    Science.gov (United States)

    2016-01-01

    Development of accelerated bridge construction (ABC) technologies has been occurring across the country, many times in : isolation. Although FHWA and others have worked to facilitate communication between these efforts, there was not a : comprehensiv...

  8. Phase and widening construction of steel bridges : [summary].

    Science.gov (United States)

    2014-03-01

    Maintaining traffic flow for bridge widening and replacement projects often requires bridges to be constructed in phases so that traffic can travel on one : portion of the bridge while another portion is being : constructed. The bridge portions are t...

  9. Second generation precast deck panel (NUDECK) system.

    Science.gov (United States)

    2010-12-01

    "The majority of todays bridge decks are built using cast-in-place concrete construction. This is due to the perceived : low initial cost and constructor familiarity with the system. This research report describes the design, details, and : constr...

  10. Construction Technology of Long Span Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    2000-01-01

    A large variety of construction methods are used during construction of major bridges, and in many cases the final structural system must be chosen with due respect to the construction process. Today the preferred construction methods are: the free-cantilever method, the launching method...

  11. Optimized Design and Testing of a Prototype Military Bridge System for Rapid In-Theater Construction

    Science.gov (United States)

    2006-11-01

    MLC 30 were applied to the system with multiple load cases for each axle, truck, and track loading. The load cases were applied sequentially to...flexural failure due to concrete crushing along the center of slab span. The failure was identified with center span cracking and associated concrete...Layer Prefabricated FRP Grids for Rapid Bridge Deck Construction: Case Study. ASCE Journal of Composites for Construction, 10, 201-121. Berg, A. C

  12. Investigation of Turbulence Effects on the Aeroelastic Properties of a Truss Bridge Deck Section

    Directory of Open Access Journals (Sweden)

    Hoang Trong Lam

    2017-12-01

    Full Text Available This paper presents the flutter derivatives (FDs extracted from a stochastic system identification (SSI method under different turbulent flows. The objective of the study is to investigate the effects of oncoming turbulence on the flutter of suspended long-span bridges using a section model wind-tunnel test. Several wind-tunnel tests were performed on a truss bridge deck section with different oncoming turbulent properties involving reduced turbulence intensities and turbulent scales. This study includes an investigation of the effect of oncoming flows on modal dynamic responses. The transient and buffeting response data from the wind-tunnel test are analyzed using the system identification technique in extracting FDs, and the difficulties involved in this method are discussed. The time-domain SSI is applied to extract all FDs simultaneously from one and two degree-of-freedom (1DOF and 2DOF systems. Finally, the results under different conditions are discussed and conclusions are formed.

  13. Effects of wet mat curing time and earlier loading on long-term durability of bridge decks : compressive strength, maturity and strength durability index (SDI).

    Science.gov (United States)

    2009-01-01

    There is increasing pressure from owners, contractors, and the public to open bridge decks sooner to full : traffic loads. As a result, a set of criteria or guidelines is needed to determine when concrete bridge decks can : safely be opened. Today, c...

  14. 77 FR 53251 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2012-08-31

    ... describing construction materials used in new Federal-aid bridge construction and bridge rehabilitation... construction materials used in new bridge construction and bridge rehabilitation projects. Data on Federal-aid... the following tables: Construction Materials for New and Replaced Bridges, a summary report which...

  15. Destructive Testing of Composite Precast Concrete Deck Panels and Buil-up Steel Plate Girders

    OpenAIRE

    Cook, Wesley J

    2010-01-01

    The Utah Department of Transportation (UDOT) has implemented the use of precast concrete panels for bridge deck construction. A bridge utilizing these panels as a reconstruction method was decommissioned three years after the new deck installation, due to unrelated matters. Two sections of this bridge were salvaged and sent to Utah State University (USU) for destructive testing. Each bridge section consisted of two built-up steel plate girders intact with the precast concrete deck panels...

  16. Bridge engineering handbook construction and maintenance

    CERN Document Server

    Chen, Wai-Fah

    2014-01-01

    Over 140 experts, 14 countries, and 89 chapters are represented in the second edition of the Bridge Engineering Handbook. This extensive collection highlights bridge engineering specimens from around the world, contains detailed information on bridge engineering, and thoroughly explains the concepts and practical applications surrounding the subject.Published in five books: Fundamentals, Superstructure Design, Substructure Design, Seismic Design, and Construction and Maintenance, this new edition provides numerous worked-out examples that give readers step-by-step design procedures, includes c

  17. Markovian bridges: Weak continuity and pathwise constructions

    OpenAIRE

    Chaumont, Loïc; Uribe Bravo, Gerónimo

    2011-01-01

    A Markovian bridge is a probability measure taken from a disintegration of the law of an initial part of the path of a Markov process given its terminal value. As such, Markovian bridges admit a natural parameterization in terms of the state space of the process. In the context of Feller processes with continuous transition densities, we construct by weak convergence considerations the only versions of Markovian bridges which are weakly continuous with respect to their parameter. We use this ...

  18. Hybrid Stainless Steel Girder for Bridge Construction

    OpenAIRE

    Tetsuya Yabuki; Yasunori Arizumi; Tetsuhiro Shimozato; Samy Guezouli; Hiroaki Matsusita; Masayuki Tai

    2017-01-01

    The main object of this paper is to present the research results of the development of a hybrid stainless steel girder system for bridge construction undertaken at University of Ryukyu. In order to prevent the corrosion damage and reduce the fabrication costs, a hybrid stainless steel girder in bridge construction is developed, the stainless steel girder of which is stiffened and braced by structural carbon steel materials. It is verified analytically and experimentally that the ultimate stre...

  19. Structural Aspects of Railway Truss Bridges Affecting Transverse Shear Forces in Steel-Concrete Composite Decks

    Directory of Open Access Journals (Sweden)

    Siekierski Wojciech

    2015-03-01

    Full Text Available At the steel-concrete interface, the horizontal shear forces that are transverse to cross beams occur due to joint action of the steel-concrete composite deck and the truss girders. Numerical analysis showed that values of the forces are big in comparison to the longitudinal shear forces. In both cases extreme force values occur near side edges of a slab. The paper studies possibilities of reduction of these shear forces by structural alterations of the following: rigidity of a concrete slab, arrangement of a wind bracing, arrangement of concrete slab expansion joints. An existing railway truss bridge span has been analysed. Numerical analysis shows that it is possible to reduce the values of shear forces transverse to cross beams. It may reach 20% near the side edges of slabs and 23% in the centre of slab width.

  20. Soil-structure interaction studies for understanding the behavior of integral abutment bridges.

    Science.gov (United States)

    2012-03-01

    Integral Abutment Bridges (IAB) are bridges without any joints within the bridge deck or between the : superstructure and the abutments. An IAB provides many advantages during construction and maintenance of : a bridge. Soil-structure interactions at...

  1. Implementation guidance for accelerated bridge construction in South Dakota

    Science.gov (United States)

    2017-09-01

    A study was conducted to investigate implementation of accelerated bridge construction (ABC) in South Dakota. Accelerated bridge construction is defined as construction practices that employ innovative techniques to reduce on-site construction time a...

  2. 75 FR 62181 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2010-10-07

    ... describing construction materials used in new Federal-aid bridge construction and bridge rehabilitation...), the FHWA has produced a report that summarizes the types of construction materials used in new bridge....fhwa.dot.gov/bridge/brdgtabs.cfm , consists of the following tables: Construction Materials for New and...

  3. 76 FR 55160 - Annual Materials Report on New Bridge Construction and Bridge Rehabilitation

    Science.gov (United States)

    2011-09-06

    ... describing construction materials used in new Federal-aid bridge construction and bridge rehabilitation... FHWA has produced a report that summarizes the types of construction materials used in new bridge....fhwa.dot.gov/bridge/brdgtabs.cfm , consists of the following tables: Construction Materials for New and...

  4. A literature survey on industrialized bridge construction.

    Science.gov (United States)

    1972-01-01

    The purpose of this survey was to aid the writer in understanding and retaining material in preparation for a project on the industrialization of bridge construction. However, it was believed that the results of the survey would be informative to oth...

  5. Construction control of cable-stayed bridges

    OpenAIRE

    Lozano Galant, José Antonio

    2013-01-01

    Premi extraordinari doctorat curs 2012-2013, àmbit d’Enginyeria Civil This work presents a study of the simulation of cable-stayed bridges built on temporary supports focused on their response during construction and in service. To simulate the behavior during construction, a set of four different algorithms has been developed to deal with initial design (Backward Algorithm), updating the tensioning process when deviations on site are measured (Forward Algorithm), optimization processes (D...

  6. Carbon fiber post-tensioned cables reduce bridge deck cracking, extend service life : research spotlight.

    Science.gov (United States)

    2008-09-01

    Side-by-side box-beam bridges are low-cost and easy to construct, : but it is difficult to inspect the interior beam webs, which can hide : potential defects such as cracking and other deterioration. A new : design reduces these problems and could do...

  7. Implementation of sustainability in bridge design, construction and maintenance.

    Science.gov (United States)

    2012-12-01

    The focus of this research is to develop a framework for more sustainable design and construction : processes for new bridges, and sustainable maintenance practices for existing bridges. The framework : includes a green rating system for bridges. The...

  8. Effect of cracking and randomness of inputs on corrosion initiation of reinforced concrete bridge decks exposed to chlorides

    Directory of Open Access Journals (Sweden)

    P. Konecny

    2017-01-01

    Full Text Available The paper is aimed at the indicative evaluation of the effect of random scatter of input parameters in case of durability of reinforced concrete bridge deck. The time to onset of corrosion of steel reinforcement of concrete bridge deck exposed to chloride is evaluated. The effect of cracking in concrete onto chloride ingress is considered. The selected steel reinforcement protection strategies are: unprotected steel reinforcement, epoxy-coated steel reinforcement and water-proof barrier bellow asphalt overlay. The preliminary model for damage effect on chloride ion ingress through water proof membrane under penetrable asphalt overlay is used. 2-D finite element chloride ingress model is combined with Monte Carlo simulation technique. The innovative crack effect modeling via highly penetrable elements is applied. Deterministic and probabilistic calculations are compared.

  9. Water Accumulation and Behavior of Surfactant Associated with Moisture Permeation in Bituminous Pavement on Concrete Deck Bridge

    OpenAIRE

    Sasaki, Iwao; Moriyoshi, Akihiro; Tsunekawa, Masami

    2006-01-01

    Water-related damage is one of the major problems for the durability of the bituminous pavement and concrete slabs of concrete deck bridges. In particular, damage can be drastically accelerated by the intervention of water and some chemicals such as surfactants and salts. Therefore, the mass transfer mechanism of water and the mechanism of chemical absorption in pavement materials are important to study. The authors previously pointed out that water storage in bituminous pavement layers is ca...

  10. The approximation function of bridge deck vibration derived from the measured eigenmodes

    Directory of Open Access Journals (Sweden)

    Sokol Milan

    2017-12-01

    Full Text Available This article deals with a method of how to acquire approximate displacement vibration functions. Input values are discrete, experimentally obtained mode shapes. A new improved approximation method based on the modal vibrations of the deck is derived using the least-squares method. An alternative approach to be employed in this paper is to approximate the displacement vibration function by a sum of sine functions whose periodicity is determined by spectral analysis adapted for non-uniformly sampled data and where the parameters of scale and phase are estimated as usual by the least-squares method. Moreover, this periodic component is supplemented by a cubic regression spline (fitted on its residuals that captures individual displacements between piers. The statistical evaluation of the stiffness parameter is performed using more vertical modes obtained from experimental results. The previous method (Sokol and Flesch, 2005, which was derived for near the pier areas, has been enhanced to the whole length of the bridge. The experimental data describing the mode shapes are not appropriate for direct use. Especially the higher derivatives calculated from these data are very sensitive to data precision.

  11. Minimum expected cost-oriented optimal maintenance planning for deteriorating structures: application to concrete bridge decks

    Energy Technology Data Exchange (ETDEWEB)

    Estes, Allen C.; Frangopol, Dan M

    2001-09-01

    Civil engineering structures are designed to serve the public and often must perform safely for decades. No matter how well they are designed, all civil engineering structures will deteriorate over time and lifetime maintenance expenses represent a substantial portion of the total lifetime cost of most structures. It is difficult to make a reliable prediction of this cost when the future is unknown and structural deterioration and behavior are assumed from a mathematical model or previous experience. An optimal maintenance program is the key to making appropriate decisions at the right time to minimize cost and maintain an appropriate level of safety. This study proposes a probabilistic framework for optimizing the timing and the type of maintenance over the expected useful life of a deteriorating structure. A decision tree analysis is used to develop an optimum lifetime maintenance plan which is updated as inspections occur and more data is available. An estimate which predicts cost and behavior over many years must be refined and reoptimized as new information becomes available. This methodology is illustrated using a half-cell potential test to evaluate a deteriorating concrete bridge deck. The study includes the expected life of the structure, the expected damage level of the structure, costs of inspection and specific repairs, interest rates, the capability of the test equipment to detect a flaw, and the management approach of the owner towards making repairs.

  12. Field performance of stress-laminated highway bridges constructed with glued laminated timber

    Science.gov (United States)

    J.P. Wacker

    2004-01-01

    This paper summarizes the field performance of three stress-laminated deck timber bridges located in Wisconsin, New York, and Arizona. The deck superstructures of these single-span highway bridges is comprised of full-span glued laminated timber (glulam) beam laminations manufactured with southern pine, hem fir/red maple combination, and/or Douglas fir lumber species....

  13. Precast concrete elements for accelerated bridge construction : laboratory testing, field testing, evaluation of a precast concrete bridge, Madison County bridge.

    Science.gov (United States)

    2009-01-01

    The importance of rapid construction technologies has been recognized by the Federal Highway Administration (FHWA) and the Iowa : DOT Office of Bridges and Structures. Recognizing this a two-lane single-span precast box girder bridge was constructed ...

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

    Science.gov (United States)

    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.

  15. Evaluation of the Buena Vista IBRD bridge : a furthering of accelerated bridge construction in Iowa.

    Science.gov (United States)

    2012-02-01

    The need to construct bridges that last longer, are less expensive, and take less time to build has increased. The importance of accelerated bridge construction (ABC) technologies has been realized by the Federal Highway Administration (FHWA) and the...

  16. Elimination of deck joints using a corrosion resistant FRP approach

    Science.gov (United States)

    Aleti, Ashok Reddy

    The research presented herein describes the development of durable link slabs for jointless bridge decks based on using FRP grid for reinforcement. Specifically, the ductility of the FRP material was utilized to accommodate bridge deck deformations imposed by girder deflection, temperature variations, and concrete shrinkage. It would also provide a solution to a number of deterioration problems associated with bridge deck joints. The design concept of the link slabs was then examined to form the basis of design for FRP grid link slabs. Improved design of FRP grid link slab/concrete deck slab interface was confirmed in the numerical analysis. The mechanical properties between the FRP grid and concrete were evaluated. The behavior of the link slab was investigated and confirmed for durability. The results indicated that the technique would allow simultaneous achievement of structural need (lower flexural stiffness of the link slab approaching the behavior of a hinge) and durability need of the link slab. Also, the development length results confirm that the bond between the FRP grid and the concrete was highly improved. The overall investigation supports the contention that durable jointless concrete bridge decks may be designed and constructed with FRP grid link slabs. It is recommended that the link slab technique be used during new construction of the bridge decks and in repair and retrofit of the bridge decks.

  17. Experimental evaluation of the buckling phenomena in the new joint design for upper deck structure of a bridge

    Directory of Open Access Journals (Sweden)

    Solazzi L.

    2010-06-01

    Full Text Available This paper is concerned with the experimental mechanical analysis of a new design of a joint for a main components of a upper deck of a road bridge. These components are subject to the compression state stress induced by the weight and the load acting on the road. Each upper deck of a bridge (positioned on each side of the bridge is composed by four tubular structures that must be joint each together. The joint must to take in to account many aspects, for example that the length of each component is not the same (because, obviously, there is a mechanical tolerance. This phenomena induce different compression stress on each component and so is very important non only the critical buckling load but also the post buckling behaviour of the structure. It is very important that if a single tubular structure reaches the critical load of instability, it still has load capacity . This is to avoid that, in the case where a column reaches the instability, the entire load acting on a column increase the load on the remaining three. For this purpose many different geometrical solutions have been designed (elaborated by fem analyses and successively tested experimentally. This work reports the main experimental results on the best joint solution and how this increase the load capacity and the displacement respect to the solution without this flange.

  18. Finishes for Wood Decks

    Science.gov (United States)

    Mark Knaebe

    2013-01-01

    Wood decks have become an important part of residential construction. Wood decks can add versatile living space to a home and, with minimal maintenance, provide decades of use. However, wood decks are exposed to high levels of stress from severe weather conditions that shrink and swell the wood. Without proper maintenance, wood decks can develop problems such as checks...

  19. Optimal construction of army ant living bridges.

    Science.gov (United States)

    Graham, Jason M; Kao, Albert B; Wilhelm, Dylana A; Garnier, Simon

    2017-12-21

    Integrating the costs and benefits of collective behaviors is a fundamental challenge to understanding the evolution of group living. These costs and benefits can rarely be quantified simultaneously due to the complexity of the interactions within the group, or even compared to each other because of the absence of common metrics between them. The construction of 'living bridges' by New World army ants - which they use to shorten their foraging trails - is a unique example of a collective behavior where costs and benefits have been experimentally measured and related to each other. As a result, it is possible to make quantitative predictions about when and how the behavior will be observed. In this paper, we extend a previous mathematical model of these costs and benefits to much broader domain of applicability. Specifically, we exhibit a procedure for analyzing the optimal formation, and final configuration, of army ant living bridges given a means to express the geometrical configuration of foraging path obstructions. Using this procedure, we provide experimentally testable predictions of the final bridge position, as well as the optimal formation process for certain cases, for a wide range of scenarios, which more closely resemble common terrain obstacles that ants encounter in nature. As such, our framework offers a rare benchmark for determining the evolutionary pressures governing the evolution of a naturally occurring collective animal behavior. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Development of bridge girder movement criteria for accelerated bridge construction.

    Science.gov (United States)

    2014-06-01

    End diaphragms connect multiple girders to form a bridge superstructure system for effective resistance to earthquake loads. Concrete : girder bridges that include end diaphragms consistently proved to perform well during previous earthquake events. ...

  1. Accelerating bridge construction to minimize traffic disruption : research spotlight.

    Science.gov (United States)

    2013-12-01

    Since 2008, MDOT has been using accelerated bridge construction, which utilizes prefabricated components and structural placements, to minimize traffic disruptions during bridge replacement or rehabilitation. A recent project provided MDOT with a new...

  2. Lean Construction Applications for Bridge Inspection

    Science.gov (United States)

    2017-10-01

    Lean philosophy was used to analyze the efficiency of bridge inspection. Emphasis was put on identifying activities that add value to the final output, an owner approved bridge inspection report. 26 bridge inspections were shadowed. Time spent on bri...

  3. A sensor network system for the health monitoring of the Parkview bridge deck.

    Science.gov (United States)

    2010-01-31

    Bridges are a critical component of the transportation infrastructure. There are approximately 600,000 bridges in : the United State according to the Federal Highway Administration. Four billion vehicles traverse these bridges daily. : Regular inspec...

  4. Polyurethane foam infill for fiber-reinforced polymer (FRP) bridge deck panels.

    Science.gov (United States)

    2014-05-01

    Although still in their infancy, fiber-reinforced polymer (FRP) bridges have shown great promise in eliminating corrosion : concerns and meeting (or exceeding) FHWAs goal of 100-year life spans for bridges. While FRP bridges are cost-effective in ...

  5. Strength Analysis of Container Deck Construction Mv. Sinar Demak Efect of Charges Container Using Finite Element Method

    OpenAIRE

    Mulyatno, Imam Pujo; Arswendo A, Berlian; Alif Maulana, Rachmat

    2012-01-01

    MV. Sinar Demak is a type container ship owned PT Samudera Shipping Services. This ship can used container up to 265 teu's. on his voyage the ship requires condition of ship is safe, especially in the construction structure. This indicates there are loads working on container deck, in operation would cause problems such as deformation, crack, and other problems. In this final project will analyze maximum stress that occur on container deck MV. Sinar Demak with the help of numerical programe F...

  6. Study on Construction Technology of Municipal Road and Bridge Concrete

    Science.gov (United States)

    Tang, Fuyong

    2018-03-01

    With the continuous development of social economy and the accelerating process of urbanization, municipal road and bridge projects have also shown a trend of rapid development. Municipal road and bridge work can fully reflect the economic and cultural development level of cities and is also an important symbol of urban development. As a basic material of construction, concrete is widely used in engineering construction. This article will analyze the municipal road and bridge concrete construction technology, put forward corresponding measures.

  7. A novel abutment construction technique for rapid bridge construction : controlled low strength Materials (CLSM) with full-height concrete panels.

    Science.gov (United States)

    2012-01-01

    One of the major obstacles facing rapid bridge construction for typical span type bridges is the time required to construct bridge abutments and foundations. This can be remedied by using the controlled low strength materials (CLSM) bridge abutment. ...

  8. Post-stressed constant depth beam concrete road and railway bridge voided decks morphology; Morfologia de tableros aligerados de canto constante postesados para puentes carreteros y ferroviarios

    Energy Technology Data Exchange (ETDEWEB)

    Yepes, V.; Alcala, J.; Diaz, J.; Gonzalez-Vidosa, F.

    2011-07-01

    In the work a study to statistically characterise 82 prestressed concrete bridge decks of real flyovers of constant depth are treated. The main objective of the study is to find design formulae with the least number of data so as to improve the preliminary design of this type of structures. The study performs an exploratory analysis and a multivariate analysis of the geometrical variables, the amount of materials and the cost for voided decks. The regression models have allowed predicting the depth of the deck as function of the span and the external void. The depth is the variable that better explains (51,9%) the cost per unit surface of the deck in road bridges, while for railway decks this variable only explains in the order of 23,4%, what implies more independent variables. The main spans and the total length in the case of the railway deck are enough to find the preliminary design of the slab with reasonable accuracy for the economic assessment of the design. (Author) 17 refs.

  9. Thermal Bridges in Building Construction - Measurements and Calculations

    DEFF Research Database (Denmark)

    Rose, Jørgen

    The thesis investigates detailed calculation methods for evaluating heat loss through building envelope constructions, or more specific, thermal bridges. First a detailed description of the calculation methods, i.e. both calculation programs and guidelines, for calculating typical thermal bridges...... calculations in more operational and applicable projecting tools, e.g. thermal bridge catalogues or U-value tables.......The thesis investigates detailed calculation methods for evaluating heat loss through building envelope constructions, or more specific, thermal bridges. First a detailed description of the calculation methods, i.e. both calculation programs and guidelines, for calculating typical thermal bridges...

  10. Comparison of conventional and internally cured concrete bridge decks in Utah : Mountain View corridor project.

    Science.gov (United States)

    2014-12-01

    The objectives of this research were to 1) monitor in-situ moisture and diffusivity for both conventional concrete : and concrete containing pre-wetted lightweight fine aggregate (LWFA), 2) compare deck performance in terms of : early-age cracking, c...

  11. Laboratory and field testing of an accelerated bridge construction demonstration bridge : US Highway 6 bridge over Keg Creek.

    Science.gov (United States)

    2013-04-01

    The US Highway 6 Bridge over Keg Creek outside of Council Bluffs, Iowa is a demonstration bridge site chosen to put into practice : newly-developed Accelerated Bridge Construction (ABC) concepts. One of these new concepts is the use of prefabricated ...

  12. Plans for crash-tested bridge railings for longitudinal wood decks

    Science.gov (United States)

    M. A. Ritter; R. K. Faller; P. D. Hilbrich Lee; B. T. Rosson; S. R. Duwadi

    1995-01-01

    In the past decade, bridge railing design criteria have moved away from static-load design and have focused on full-scale crash testing as a more appropriate and reliable means of evaluating bridge railings. The five bridge railing plans presented reflect the results of a cooperative research project between the Midwest Roadside Safety Facility, University of Nebraska...

  13. Evaluation of stainless steel reinforcement construction project

    Science.gov (United States)

    2003-02-01

    Stainless steel reinforcement has greater corrosion resistance than that of the conventional reinforcement. In this project, bridge A6059, the first in Missouri utilizing stainless steel reinforcement in the deck, was constructed, along with bridge A...

  14. Evaluation of lightweight high performance concrete in bulb-T beams and decks in two bridges on Route 33 in Virginia.

    Science.gov (United States)

    2009-01-01

    Lightweight high performance concrete (LWHPC) is expected to provide high strength and high durability along with reduced weight. The purpose of this research was to evaluate and compare the prestressed LWHPC bulb-T beams and decks in two bridge stru...

  15. ON RIVER POLLUTION DURING CONSTRUCTION AND CAPITAL REPAIR OF BRIDGES

    OpenAIRE

    L. Gulitskaya; N. Kushtch; O. Shimanskaya

    2012-01-01

    The paper describes a problem pertaining to river pollution during construction and capital repair of bridges and some proposals have been given how to solve the problem concerned. The main sources and types of pollution have been determined in the paper. The paper contains recommendations on  decrease of  river pollution during construction, repair and maintenance of bridges

  16. Design of Experimental Suspended Footbridge with Deck Made of UHPC

    Directory of Open Access Journals (Sweden)

    Blank Marek

    2016-01-01

    Full Text Available This paper deals with the static and dynamic design of experimental footbridge for pedestrians and cyclists in the municipality Lužec nad Vltavou in Czech Republic, Europe. This work aims to familiarize the reader with calculations carried out and the results obtained, describing the static and dynamic properties of proposed footbridge. The construction of footbridge is designed as a suspended structure with prestressed bridge deck consisting of prefabricated UHPC panels and reversed “V” shaped steel pylon with height of approximately 40 meters. The deck is anchored using 24 steel hangers in one row in a steel pylon - 17 ropes in the main span and 7 cables on the other side. Range of the main span is 99.18 meters and the secondary span is 31.9 m. Deck width is 4.5 meters with 3.0 meters passing space. The bridge is designed for the possibility of passage of vehicles weighting up to 3.5 tons. Deck panels are made of UHPC with reinforcement. At the edge of the bridge on the side of the shorter span the bridge deck is firmly connected with abutment and on the other deck it is stored using a pair of sliding bearings. The utilization of the excellent properties of UHPC allows to design a very thin and lightweight construction of the deck, which could not be achieved with the use of normal concrete.

  17. Construction engineering of steel tub-girder bridge systems for skew effects

    Science.gov (United States)

    Jimenez Chong, Juan Manuel

    Closed structural sections, such as those having circular, rectangular or trapezoidal shape, possess high rotational rigidity when compared to open sections such as I-girders. The high torsional rigidity of closed sections makes them ideal for use in highly curved bridges. In this case, the geometry of the bridge results in large torsional forces. Because of structural efficiency and economy reasons, most of these closed-section bridges consist of a trapezoidal cross-section, with a top concrete slab and bottom and side steel plates. The slab is cast after the steel is erected and thus a system of internal diaphragms and braces is necessary to stabilize the system during erection. During the steel erection and the early stages of the concrete deck placement, the section can be considered as quasi-closed as the top concrete flange has not been cast or is not yet effective. During steel erection, undetermined and/or large torsional forces and/or displacements may result in fit-up problems requiring large stresses to overcome. During concrete deck placement, the undetermined displacements can affect the control of the deck thickness and the final deck geometry, such as the alignment of deck joints and the matching of stages in phased constructions projects. Due to the interactions between their various components, the behavior of curved and skewed tub-girder bridges is significantly more complex than that of straight bridges. When skewed supports are used in tub-girders, the interaction of the girder bending rotations and the displacement constraints induced by the skewed support diaphragms causes twisting of the girders at the supports. These twist rotations introduce additional torques into the system. Both curvature and skew can cause design and construction difficulties, especially at the supports, where the corresponding steel dead load deflections and the large torsional stiffness of the girders may lead to large fit-up forces. Currently, the general

  18. Rapid replacement/construction of bridges.

    Science.gov (United States)

    2012-11-01

    Bridges are a key element of the transportation system because they control system capacity and are normally built at : the highest cost to the system. Once a bridge reaches its useful design service life, it needs to be replaced or : reconstructed i...

  19. Disturbance indicator benchmark for urban bridge construction

    NARCIS (Netherlands)

    Brouwer, J.; Vogel, R.; Thodesen, C.

    2013-01-01

    European bridges are today in a state of particular concern with over 50% of European urban bridges being more than 40 years old and thus requiring considerable maintenance or possibly even replacement [1]. This means that interventions in the present infrastructure have to be made while ensuring

  20. Design, construction and load testing of the bridge on Arnault Branch, Washington County, Missouri using innovative technologies.

    Science.gov (United States)

    2010-02-01

    The superstructure and instrumentation designs of a three-span bridge are presented in this report. The three spans include a : precast box-girder bridge, a precast deck on steel girder and a precast deck on concrete girder. They were designed to com...

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

    Science.gov (United States)

    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

  2. STRENGTH ANALYSIS OF CONTAINER DECK CONSTRUCTION MV. SINAR DEMAK EFECT OF CHARGES CONTAINER USING FINITE ELEMENT METHOD

    OpenAIRE

    Imam Pujo Mulyatno; Berlian Arswendo A; Rachmat Alif Maulana

    2013-01-01

    Abstract MV. Sinar Demak is a type container ship owned PT Samudera Shipping Services. This ship can used container up to 265 teu’s. on his voyage the ship requires condition of ship is safe, especially in the construction structure. This indicates there are loads working on container deck, in operation would cause problems such as deformation, crack, and other problems. In this final project will analyze maximum stress that occur on container deck MV. Sinar Demak with the help of numerical p...

  3. Numerical Simulation of Early Age Cracking of Reinforced Concrete Bridge Decks with a Full-3D Multiscale and Multi-Chemo-Physical Integrated Analysis

    Directory of Open Access Journals (Sweden)

    Tetsuya Ishida

    2018-03-01

    Full Text Available In November 2011, the Japanese government resolved to build “Revival Roads” in the Tohoku region to accelerate the recovery from the Great East Japan Earthquake of March 2011. Because the Tohoku region experiences such cold and snowy weather in winter, complex degradation from a combination of frost damage, chloride attack from de-icing agents, alkali–silica reaction, cracking and fatigue is anticipated. Thus, to enhance the durability performance of road structures, particularly reinforced concrete (RC bridge decks, multiple countermeasures are proposed: a low water-to-cement ratio in the mix, mineral admixtures such as ground granulated blast furnace slag and/or fly ash to mitigate the risks of chloride attack and alkali–silica reaction, anticorrosion rebar and 6% entrained air for frost damage. It should be noted here that such high durability specifications may conversely increase the risk of early age cracking caused by temperature and shrinkage due to the large amounts of cement and the use of mineral admixtures. Against this background, this paper presents a numerical simulation of early age deformation and cracking of RC bridge decks with full 3D multiscale and multi-chemo-physical integrated analysis. First, a multiscale constitutive model of solidifying cementitious materials is briefly introduced based on systematic knowledge coupling microscopic thermodynamic phenomena and microscopic structural mechanics. With the aim to assess the early age thermal and shrinkage-induced cracks on real bridge deck, the study began with extensive model validations by applying the multiscale and multi-physical integrated analysis system to small specimens and mock-up RC bridge deck specimens. Then, through the application of the current computational system, factors that affect the generation and propagation of early age thermal and shrinkage-induced cracks are identified via experimental validation and full-scale numerical simulation on real

  4. STRENGTH ANALYSIS OF CONTAINER DECK CONSTRUCTION MV. SINAR DEMAK EFECT OF CHARGES CONTAINER USING FINITE ELEMENT METHOD

    Directory of Open Access Journals (Sweden)

    Imam Pujo Mulyatno

    2013-01-01

    Full Text Available Abstract MV. Sinar Demak is a type container ship owned PT Samudera Shipping Services. This ship can used container up to 265 teu’s. on his voyage the ship requires condition of ship is safe, especially in the construction structure. This indicates there are loads working on container deck, in operation would cause problems such as deformation, crack, and other problems. In this final project will analyze maximum stress that occur on container deck MV. Sinar Demak with the help of numerical programe FEM software. This analysis is used a static load analysis to determine of characteristics, location of the largest stress and safety factor of container deck construction structure based on variation of the condition state of vessel. The result using numerical programe FEM software obtained maximum stress on the container deck construction structure on sagging condition is 247 N/mm2 at node 89696 at the frame no 23. Safety factor is true for all condition, safety factor to still water condition is 2,17 for  criteria of materials and 1,55 for BKI standard, safety factor for hogging condition is 2,17 for criteria of materials and 1,55 for BKI standard, and safety factor for sagging condition is 1,61 for criteria of materials and 1,157 for BKI standard.

  5. Rational load rating of deck-girder bridges with girder end shear cracks in reverse orientation.

    Science.gov (United States)

    2017-04-01

    Reverse diagonal shear cracking at reinforced concrete girder supports affects many low-volume bridges built : in the early 1900s in Kansas. This phenomenon, however, is not addressed in the American Association of State : Highway and Transportation ...

  6. Rapid replacement of bridge deck expansion joints study - phase I : [tech transfer summary].

    Science.gov (United States)

    2014-12-01

    This initial research phase focused on documenting the current : means and methods of bridge expansion joint deterioration, : maintenance, and replacement and on identifying improvements : through all of the input gathered.

  7. Identification of causes and solution strategies for deck cracking in jointless bridges : research report.

    Science.gov (United States)

    2012-07-01

    Bridges have traditionally relied on a system of expansion joints and flexible bearings to accommodate movements due to temperature, creep, and shrinkage loading. Joints and elements in their vicinity experience a high amount of degradation; thus mod...

  8. Identification of Causes and Solution Strategies for Deck Cracking in Jointless Bridges : Technical Report Documentation Page

    Science.gov (United States)

    2012-07-30

    Bridges have traditionally relied on a system of expansion joints and flexible bearings to accommodate movements due to temperature, creep, and shrinkage loading. Joints and elements in their vicinity experience a high amount of degradation; thus mod...

  9. Moving dynamic loads caused by bridge deck joint unevenness - a case study

    CSIR Research Space (South Africa)

    Steyn, WJV

    2004-11-01

    Full Text Available be performed with data from other bridges in South Africa. 5. REFERENCES Cebon, D, 1999. Handbook of Vehicle-Road Interaction. Advances in Engineering 2, Lisse, The Netherlands: Swets & Zeitlinger. Gillespie, TD, 1992, Fundamentals...

  10. Development of a Bridge Construction Live Load Analysis Guide : Brief

    Science.gov (United States)

    2012-04-01

    The dramatic and disastrous collapse of the I-35W Mississippi River bridge in Minneapolis in 2007 drew attention to a number of issues in bridge construction and rehabilitation. Though a prime cause of the collapse were the gusset plates underdesigne...

  11. Application of Composite Structures in Bridge Engineering. Problems of Construction Process and Strength Analysis

    Directory of Open Access Journals (Sweden)

    Flaga Kazimierz

    2015-03-01

    Full Text Available Steel-concrete composite structures have been used in bridge engineering from decades. This is due to rational utilisation of the strength properties of the two materials. At the same time, the reinforced concrete (or prestressed deck slab is more favourable than the orthotropic steel plate used in steel bridges (higher mass, better vibration damping, longer life.

  12. An industrialized construction approach to concrete superstructures for bridges.

    Science.gov (United States)

    1974-01-01

    The objective of this study was to develop drawings for a specific site or sites that incorporated the best concepts of industrialized bridge superstructure construction, that is, great emphasis was placed upon the use of modular design and assembly ...

  13. Rapid bridge construction technology : precast elements for substructures.

    Science.gov (United States)

    2011-06-01

    The goal of this research was to propose an alternate system of precast bridge substructures which can : substitute for conventional cast in place systems in Wisconsin to achieve accelerated construction. : Three types of abutment modules (hollow wal...

  14. Accelerating Bridge Construction to Reduce Congestion

    Science.gov (United States)

    2011-05-01

    The magnitude of the "residual" displacements at the end of an earthquake can affect the amount of time needed to restore a bridge to service. It may be possible to reduce these displacements (and downtimes) by introducing prestressing forces into br...

  15. Plans for crash-tested bridge railings for longitudinal wood decks on low-volume roads

    Science.gov (United States)

    Michael A. Ritter; Ronald K. Faller; Steve. Bunnell; Paula D. Hilbrich Lee; Barry T. Rosson

    1998-01-01

    The plans for crashworthy bridge railings for low-volume roads were developed through a cooperative research program involving the USDA Forest Service, Forest Products Laboratory (FPL); the Midwest Roadside Safety Facility, University of Nebraska-Lincoln (MwRSF); and the Forest Service, National Forest System, Engineering. Three railings were developed and successfully...

  16. Laser welded steel sandwich panel bridge deck development : finite element analysis and stake weld strength tests.

    Science.gov (United States)

    2009-09-01

    This report summarizes the analysis of laser welded steel sandwich panels for use in bridge structures and : static testing of laser stake welded lap shear coupons. Steel sandwich panels consist of two face sheets : connected by a relatively low-dens...

  17. Evaluation of corrosion inhibitors for concrete bridge deck patches and overlays.

    Science.gov (United States)

    2003-01-01

    This report presents the results to date of a national pooled fund study initiated in August 1996 to evaluate the long-term performance of bridges and outdoor exposure slabs damaged by chloride-induced corrosion that have concrete containing corrosio...

  18. The Influence of the Track Axis Curvature at Railway Filler-Beam Deck Bridges

    Directory of Open Access Journals (Sweden)

    Răzvan Marian Stănescu

    2016-06-01

    Full Text Available The article presents a comparative study between the simplified method calculation proposed by the prescriptions of design codes and the analysis with the FEM program LUSAS [1], regarding the influence of the curvature of the track axis at railway bridges with steel beams embedded in concrete.

  19. Determination of brace forces caused by construction loads and wind loads during bridge construction.

    Science.gov (United States)

    2014-04-01

    The first objective of this study was to develop procedures for determining bracing forces during bridge construction. : Numerical finite element models and analysis techniques were developed for evaluating brace forces induced by construction loads ...

  20. Demonstration and Validation of a Composite Grid Reinforcement System for Bridge Decks

    Science.gov (United States)

    2016-09-01

    loss testing suggest the Fort Knox Bridge No. 4 site is a C3 classification of at- mospheric corrosion severity. Although the steel coupon testing...Table 4. Summary of results from the 6-month ASTM G1 mass loss test and corrosion classification per ISO 9223:2012. 1010 Steel CDA101 Al6061...at- mospheric corrosion severity. Although the steel coupon testing resulted in a C2 classification , the results were on the upper limit of the

  1. Construction of prestressed concrete single-tee bridge superstructures.

    Science.gov (United States)

    1977-01-01

    This report discusses in detail the construction of the first five precast, prestressed concrete, single-tee beam bridge superstructures to be let to contract in Virginia. The data suggest that this single-tee beam enables efficient construction of t...

  2. AN ACD DIAGRAM DEVELOPED FOR SIMULATING A BRIDGE CONSTRUCTION OPERATION

    Directory of Open Access Journals (Sweden)

    Fahimeh Zaeri

    2014-12-01

    Full Text Available Success in the performance of construction projects can be substantially enhanced if plans are formulated more realistically, ahead of time. Planning includes identifying project activities, required resources, interdependencies, and also recognizing the uncertainties in the duration of activities. Inherent features of construction projects, such as high repetition, complexity and uniqueness on the one hand, and advances in technology and methodologies on the other, create more difficulties in planning construction delivery. This is true for bridge operations. This study presents an innovative incremental beam launching method with twin truss gantry. This construction method has significant advantages in terms of cost and speed of performance, but increases the level of planning and management required for the bridge operation. Further, because of the newness of the method, no specific Work Breakdown Structure nor conceptual framework has been developed as yet. The aim of the current study is to explore the use of a simulation-based tool (EZStrobe to facilitate the planning and management of a bridge construction operation (case study. The process followed in the development of a conceptual framework for the case study project is described. An Activity Cycle Diagram is produced alongside the conceptual framework and process models, with the intent of illustrating the key steps in the simulation modelling method. The developed models could assist in scheduling and controlling inherent construction features such as uncertainties, complexities, and repetitions in bridge construction projects, consequently improving their delivery.

  3. Design of ultra high performance concrete as an overlay in pavements and bridge decks.

    Science.gov (United States)

    2014-08-01

    The main objective of this research was to develop ultra-high performance concrete (UHPC) as a reliable, economic, low carbon foot : print and durable concrete overlay material that can offer shorter traffic closures due to faster construction. The U...

  4. 78 FR 71546 - Safety Zone; Belt Parkway Bridge Construction, Gerritsen Inlet, Brooklyn, NY

    Science.gov (United States)

    2013-11-29

    ... 1625-AA00 Safety Zone; Belt Parkway Bridge Construction, Gerritsen Inlet, Brooklyn, NY AGENCY: Coast... the construction of the Bridge. DATES: Comments and related material must be received by the Coast... construction and demolition of Belt Parkway Bridge. There is no previous regulatory action for this Bridge. C...

  5. CHES and ASHE build bridges in construction.

    Science.gov (United States)

    Burrill, Gordon D

    2007-08-01

    The Canadian Healthcare Engineering Society (CHES) and the American Society for Healthcare Engineering (ASHE) are partnering with a significant education initiative. They are providing construction and contract personnel with the insights necessary to recognise the inherent risks of progressing healthcare facility projects in patient-occupied buildings, writes Gordon D. Burrill, P. Eng.

  6. Effect of voids in grouted, post-tensioned concrete bridge construction : seminar slides.

    Science.gov (United States)

    2009-02-26

    Post-tensioned (PT) bridges have several advantages over other bridge types: they can span longer distances, can be constructed relatively fast, and are economical. The tendons of PT bridges are critical components, essentially the backbone of the PT...

  7. Implementation of sustainable and green design and construction practices for bridges.

    Science.gov (United States)

    2012-12-01

    The focus of this research is to develop a framework for more sustainable design and construction : processes for new bridges, and sustainable maintenance practices for existing bridges. The framework : includes a green rating system for bridges. The...

  8. Construction and Design of Post-Tensioned Pearl-Chain Bridges using SL-Technology

    DEFF Research Database (Denmark)

    Halding, Philip Skov

    2016-01-01

    Pre‐fabricated closed‐spandrel concrete arch bridges have existed for more than 50 years. Pearl‐Chain (PC) Bridges are a new award‐winning state‐of‐the‐art segmental concrete arch bridge concept invented by professor Kristian Hertz. A PC‐Arch can consist of a number of pre‐tensioned low‐weight SL......‐Decks. One SL‐Deck is a combination of light aggregate concrete, and regular concrete. Curved post‐tensioning ducts are cast into the elements, and several SL‐Decks are post‐tensioned together in an arch shape to become a PC‐Arch. A PC‐Bridge is built by erecting a number of adjacent PC‐Arches and applying......‐Bridge. The case showed that the pre‐compression in the arch from pre‐stressing, rise/to span ratio, and layer thickness of the filling as expected had influence on the capacity and could be altered to meet the capacity demands of a specific project. For an unevenly loaded bridge, in general, the lowest capacity...

  9. Construction of a Dip Tank for Finishing Wood Siding or Decking

    Science.gov (United States)

    Mark Knaebe

    2013-01-01

    Dipping new siding or decking pieces before installation is faster than finishing after installation, and it gets finish on the backside and ends of the pieces, thereby extending their service life. This method is appropriate for any penetrating finish, such as waterrepellent preservatives or semitransparent stains. It may also be used to pre-treat siding with water-...

  10. Aluminium bridges, aluminium bridge decks

    NARCIS (Netherlands)

    Soetens, F.; Straalen, IJ.J. van

    2003-01-01

    Applications of aluminium have grown considerably in building and civil engineering the last decade. In building and civil engineering the increase of aluminium applications is due to various aspects like light weight, durability and maintenance, use of extrusions, and esthetics. The paper starts

  11. 76 FR 42545 - Regulated Navigation Area; Chelsea Street Bridge Construction, Chelsea, MA

    Science.gov (United States)

    2011-07-19

    ...-AA11 Regulated Navigation Area; Chelsea Street Bridge Construction, Chelsea, MA AGENCY: Coast Guard... navigable waters during the construction of the Chelsea Street Bridge. DATES: This rule is effective in the... questions or comments, during the bridge construction. We will provide written summaries of any such...

  12. 77 FR 1870 - Safety Zone; Matlacha Bridge Construction, Matlacha Pass, Matlacha, FL

    Science.gov (United States)

    2012-01-12

    ...-AA00 Safety Zone; Matlacha Bridge Construction, Matlacha Pass, Matlacha, FL AGENCY: Coast Guard, DHS... be enforced during construction of the Matlacha Bridge from Thursday, December 15, 2011 until Sunday... United States during the Matlacha Bridge construction. Persons and vessels are prohibited from entering...

  13. 75 FR 38923 - Regulated Navigation Area: Niantic Railroad Bridge Construction, Niantic, CT

    Science.gov (United States)

    2010-07-07

    ...-AA11 Regulated Navigation Area: Niantic Railroad Bridge Construction, Niantic, CT AGENCY: Coast Guard... on the navigable waters during the construction of the Niantic Railroad Bridge. DATES: This rule is... public questions or comments, during the bridge construction. We will provide written summaries of any...

  14. 33 CFR 115.60 - Procedures for handling applications for bridge construction permits.

    Science.gov (United States)

    2010-07-01

    ... applications for bridge construction permits. 115.60 Section 115.60 Navigation and Navigable Waters COAST GUARD... Procedures for handling applications for bridge construction permits. The following procedures will be..., the District Commander verifies the authority for construction of the bridge, reviews, the application...

  15. 77 FR 70891 - Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA

    Science.gov (United States)

    2012-11-28

    ...-AA00 Safety Zone; Bay Bridge Construction, San Francisco Bay, San Francisco, CA AGENCY: Coast Guard... construction of the Bay Bridge, the safety zone is necessary to provide for the safety of mariners transiting... zones (33 U.S.C. 1221 et seq.). CALTRANS will sponsor the Bay Bridge Construction Safety Zone on...

  16. 78 FR 37969 - Safety Zone; South Park Bridge Construction, Lower Duwamish Waterway, Seattle, WA

    Science.gov (United States)

    2013-06-25

    ...-AA00 Safety Zone; South Park Bridge Construction, Lower Duwamish Waterway, Seattle, WA AGENCY: Coast...-construction of the bridge. The safety zone is necessary to ensure the safety of the maritime public and workers involved in the bridge construction. The safety zone will prohibit any person or vessel from...

  17. 77 FR 20719 - Safety Zone; Matlacha Bridge Construction, Matlacha Pass, Matlacha, FL

    Science.gov (United States)

    2012-04-06

    ...-AA00 Safety Zone; Matlacha Bridge Construction, Matlacha Pass, Matlacha, FL AGENCY: Coast Guard, DHS... be enforced during construction of the Matlacha Bridge from Monday, March 12, 2012 through Tuesday... United States during the Matlacha Bridge construction. Persons and vessels are prohibited from entering...

  18. 76 FR 57910 - Regulated Navigation Area; Route 24 Bridge Construction, Tiverton and Portsmouth, RI

    Science.gov (United States)

    2011-09-19

    ...-AA11 Regulated Navigation Area; Route 24 Bridge Construction, Tiverton and Portsmouth, RI AGENCY: Coast... surrounding construction of the new Route 24 bridge that crosses the Sakonnet River between Tiverton and... waterway users, the public, and construction workers for the duration of the new Route 24 bridge...

  19. 75 FR 21990 - Safety Zone; Extended Debris Removal in the Lake Champlain Bridge Construction Zone (Between...

    Science.gov (United States)

    2010-04-27

    ...-AA00 Safety Zone; Extended Debris Removal in the Lake Champlain Bridge Construction Zone (Between... surrounding the Lake Champlain Bridge construction zone between Chimney Point, VT and Crown Point, NY. This... north and south of the Lake Champlain Bridge construction site. The Captain of the Port may suspend part...

  20. Benefits of measuring half-cell potentials and rebar corrosion rates in condition surveys of concrete bridge decks.

    Science.gov (United States)

    1992-01-01

    The practice of conducting a half-cell potential survey during the assessment of the condition of a concrete deck was reexamined with the objective of eliminating some of the doubts concerning its benefits. It was found that the survey grid size of 4...

  1. Application of Composite Structures in Bridge Engineering. Problems of Construction Process and Strength Analysis

    Science.gov (United States)

    Flaga, Kazimierz; Furtak, Kazimierz

    2015-03-01

    Steel-concrete composite structures have been used in bridge engineering from decades. This is due to rational utilisation of the strength properties of the two materials. At the same time, the reinforced concrete (or prestressed) deck slab is more favourable than the orthotropic steel plate used in steel bridges (higher mass, better vibration damping, longer life). The most commonly found in practice are composite girder bridges, particularly in highway bridges of small and medium spans, but the spans may reach over 200 m. In larger spans steel truss girders are applied. Bridge composite structures are also employed in cable-stayed bridge decks of the main girder spans of the order of 600, 800 m. The aim of the article is to present the cionstruction process and strength analysis problems concerning of this type of structures. Much attention is paid to the design and calculation of the shear connectors characteristic for the discussed objects. The authors focused mainly on the issues of single composite structures. The effect of assembly states on the stresses and strains in composite members are highlighted. A separate part of problems is devoted to the influence of rheological factors, i.e. concrete shrinkage and creep, as well as thermal factors on the stresses and strains and redistribution of internal forces.

  2. Analysis of an Orthotropic Deck Stiffened with a Cement-Based Overlay

    DEFF Research Database (Denmark)

    Walter, Rasmus; Olesen, John Forbes; Stang, Henrik

    2007-01-01

    structure, the Farø bridges located in Denmark, are analyzed. The steel box girders of the Farø bridges spans 80 m, and have a depth of 3.5 m, and a width of 19.5 m. The focus of the present study is the top part of the steel box girders, which is constructed as an orthotropic deck plate. Numerous factors......Over the past years, with increasing traffic volumes and higher wheel loads, fatigue damage in steel parts of typical orthotropic steel bridge decks has been experienced on heavily trafficked routes. A demand exists to find a durable system to increase the fatigue safety of orthotropic steel bridge...... the finite-element method. The stiffness of the steel deck reinforced with an overlay depends highly on the composite action. The composite action is closely related to cracking of the overlay and interfacial cracking between the overlay and underlying steel plate (debonding). As an example, a real size...

  3. RECONSTRUCTION AND REINFORCEMENT OF BRIDGE ACROSS THE RIVER. SYLVA IN KUNGUR, RUSSIA

    Directory of Open Access Journals (Sweden)

    R. Ye. Heizn

    2010-04-01

    Full Text Available Sylva Bridge at Kungur city is one of the oldest road bridges in Perm region, the West Urals, Russia. Its erection was begun in 1912 and was interrupted with the First World War and the further events in Russia. The bridge was opened only in 1931. For 75 years of bridge operation the most part of bridge constructions has been acquired plural damages, both mechanical and corrosion. After the bridge inspection in 2003 and according to the calculations of its capacity, the decision on reconstruction of the bridge was accepted. The purpose of rehabilitation was to replace the timber deck by steel orthotropic deck with asphalt pavement. A new deck was to be engaged in combined action with the existing metal structures with the help of socles with high-strength bolts. Due to this, the bridge carrying capacity was increased as required by the present standards. In 2006, after tests, the bridge was opened for traffic.

  4. MASH test 3-11 of the TxDOT single slope bridge rail (type SSTR) on pan-formed bridge deck

    Science.gov (United States)

    2011-03-01

    The objective of this crash test was to determine whether the TxDOT Single Slope Traffic Rail (Type : SSTR) would perform acceptably on a pan-formed deck when tested according to the guidelines set forth in : Manual for Assessing Safety Hardware (MAS...

  5. 76 FR 65376 - Regulated Navigation Area; Chelsea Street Bridge Construction, Chelsea, MA

    Science.gov (United States)

    2011-10-21

    ...-AA11 Regulated Navigation Area; Chelsea Street Bridge Construction, Chelsea, MA AGENCY: Coast Guard... opportunity for public questions or comments, during the bridge construction. We will provide written... Area (RNA) on the navigable waters of the Chelsea River under and surrounding the Chelsea Street Bridge...

  6. Modal analysis of cable-stayed UHPC bridge

    Directory of Open Access Journals (Sweden)

    Tej Petr

    2017-01-01

    Full Text Available This paper deals with the dynamic analysis of cable-stayed UHPC bridge over the Vltava river near town Melnik in Czech Republic, Europe. Bridge serves for pedestrians and cyclists. This work aims to familiarize the reader with dynamic calculations carried out and the results obtained, describing the dynamic properties of proposed bridge. The construction of bridge is designed as a cable-stayed structure with prestressed bridge deck consisting of prefabricated UHPC panels and reversed “V” shaped steel pylon with height of approximately 40 meters. The deck is anchored using 24 steel hangers in one row in a steel pylon - 17 ropes in the main span and 7 cables on the other side. Range of the main span is 99.18 meters and the secondary span is 31.9 m. Deck width is 4.5 meters with 3.0 meters passing space. The bridge is designed for the possibility of passage of vehicles weighting up to 3.5 tonnes. Deck panels are made of UHPC with reinforcement. At the edge of the bridge on the side of the shorter span the bridge deck is firmly connected with abutment and on the other deck it is stored using a pair of sliding bearings.

  7. Accelerated bridge construction utilizing precast pier caps on state highway 69 over Turkey Creek, Huerfano County, CO.

    Science.gov (United States)

    2014-07-01

    The purpose of this report is to document Accelerated Bridge Construction (ABC) techniques on IBRD : (Innovative Bridge Research and Development) project 102470 for the construction of Bridge N-16-Q : on State Highway 69 over Turkey Creek. The constr...

  8. Traditionally Sustainability Analyses of Hydraulic-Architectural Bridge Construction in Iran

    OpenAIRE

    Karim Shiraazi; Zargham OstadiAsl; Vahid Sheikhloie; Ahadollah Azami; Shahin Hassanimehr

    2012-01-01

    Bridge is an architectural symbol in Iran as Badgir (wind catcher); fire temples and arch are vaults are such. Therefore, from the very old ages, construction of bridges in Iran has mixed with architecture, social customs, alms and charity and holiness. Since long ago, from Mad, Achaemenid, Parthian and Sassanid times which construction of bridges got an inseparable relation with social dependency and architecture, based on those dependency bridges and dams got holy names; as Dokhtar...

  9. ABC deck panel testing.

    Science.gov (United States)

    2013-09-01

    Accelerated Bridge Construction techniques have resulted in innovative options that : save time and money during the construction of bridges. One such group of techniques : that has generated considerable interest is the usage of individual precast c...

  10. Site Characterization during Bridge Foundation Construction Using Electrical Resistivity Tomography

    Directory of Open Access Journals (Sweden)

    Aleksandra V. Varnavina

    2016-07-01

    Full Text Available A shallow underground water-filled cavity was encountered in limestone bedrock during the construction of a new column footing for the Gasconade River Bridge over Interstate 44. Five electrical resistivity tomography (ERT profiles and borehole control were acquired in immediate proximity to the existing and the new column footings in order to assess the integrity of the rock beneath the foundation columns and characterize the encountered cavity. Two parallel southwest- northeast trending fracture zones were identified on the acquired ERT profiles and competent rock was differentiated from more extensively fractured rock. The volumetric extent of the void was mapped based on the interpretation of the ERT, borehole and injected grout data. A conceptual model for the development of the water-filled cavity was proposed.

  11. Effects of bridge construction on songbirds and small mammals at Blennerhassett Island, Ohio River, USA.

    Science.gov (United States)

    Vance, Joshua A; Angus, Norse B; Anderson, James T

    2013-09-01

    Construction of man-made objects such as roads and bridges may have impacts on wildlife depending on species or location. We investigated songbirds and small mammals along the Ohio River, WV, USA at a new bridge both before and after construction and at a bridge crossing that was present throughout the study. Comparisons were made at each site over three time periods (1985-1987 [Phase I] and 1998-2000 [Phase II] [pre-construction], 2007-2009 [Phase III] [post-construction]) and at three distances (0, 100, 300 m) from the bridge or proposed bridge location. Overall, 70 songbirds and 10 small mammals were detected during the study. Cliff swallows (Petrochelidon pyrrhonota) and rock pigeons (Columba livia) showed high affinity for bridges (P 0.05). Species richness and diversity for songbirds and small mammals did not differ before and after bridge construction (P > 0.05). We found that most species sampled did not respond to the bridge crossing, and believe that the bridge is not causing any measurable negative density impacts to the species we investigated. The new bridge does provide habitat for exotic rock pigeons that are adjusted to man-made structures for nesting.

  12. Effect of voids in grouted, post-tensioned concrete bridge construction : volume 2--inspection, repair, materials, and risks.

    Science.gov (United States)

    2009-09-01

    Post-tensioned (PT) bridges are major structures that carry significant traffic. These bridges are designed and : constructed because they are economical for spanning long distances. In Texas, there are several signature PT : bridges. In the late 199...

  13. Long-term behavior of integral abutment bridges : appendix A, construction plans.

    Science.gov (United States)

    2011-01-01

    Integral abutment (IA) construction has become the preferred method over conventional construction for use with typical highway bridges. However, the use of these structures is limited due to state mandated length and skew limitations. To expand thei...

  14. Construction simulation analysis of 120m continuous rigid frame bridge based on Midas Civil

    Science.gov (United States)

    Shi, Jing-xian; Ran, Zhi-hong

    2018-03-01

    In this paper, a three-dimensional finite element model of a continuous rigid frame bridge with a main span of 120m is established by the simulation and analysis of Midas Civil software. The deflection and stress of the main beam in each construction stage of continuous beam bridge are simulated and analyzed, which provides a reliable technical guarantee for the safe construction of the bridge.

  15. 78 FR 59237 - Regulated Navigation Area-Weymouth Fore River, Fore River Bridge Construction, Weymouth and...

    Science.gov (United States)

    2013-09-26

    ...-AA11 Regulated Navigation Area--Weymouth Fore River, Fore River Bridge Construction, Weymouth and... necessary to provide for the safety of life in the vicinity of the Fore River Bridge during its construction.... Mark Cutter, Coast Guard Sector Boston Waterways Management Division, telephone 617-223-4000, email...

  16. 78 FR 7670 - Safety Zone; Indian Street Bridge Construction, St. Lucie Canal, Palm City, FL

    Science.gov (United States)

    2013-02-04

    ... 1625-AA00 Safety Zone; Indian Street Bridge Construction, St. Lucie Canal, Palm City, FL AGENCY: Coast... zone on the St. Lucie Canal, Palm City, Florida to provide for the safety of life and vessels on a... Street Bridge in Palm City, Florida. The construction will impede the safe navigation of vessel traffic...

  17. Strain features and condition assessment of orthotropic steel deck cable-supported bridges subjected to vehicle loads by using dense FBG strain sensors

    Science.gov (United States)

    Wei, Shiyin; Zhang, Zhaohui; Li, Shunlong; Li, Hui

    2017-10-01

    Strain is a direct indicator of structural safety. Therefore, strain sensors have been used in most structural health monitoring systems for bridges. However, until now, the investigation of strain response has been insufficient. This paper conducts a comprehensive study of the strain features of the U ribs and transverse diaphragm on an orthotropic steel deck and proposes a statistical paradigm for crack detection based on the features of vehicle-induced strain response by using the densely distributed optic fibre Bragg grating (FBG) strain sensors. The local feature of strain under vehicle load is highlighted, which enables the use of measurement data to determine the vehicle loading event and to make a decision regarding the health status of a girder near the strain sensors via technical elimination of the load information. Time–frequency analysis shows that the strain contains three features: the long-term trend item, the short-term trend item, and the instantaneous vehicle-induced item (IVII). The IVII is the wheel-induced strain with a remarkable local feature, and the measured wheel-induced strain is only influenced by the vehicle near the FBG sensor, while other vehicles slightly farther away have no effect on the wheel-induced strain. This causes the local strain series, among the FBG strain sensors in the same transverse locations of different cross-sections, to present similarities in shape to some extent and presents a time delay in successive order along the driving direction. Therefore, the strain series induced by an identical vehicle can be easily tracked and compared by extracting the amplitude and calculating the mutual ratio to eliminate vehicle loading information, leaving the girder information alone. The statistical paradigm for crack detection is finally proposed, and the detection accuracy is then validated by using dense FBG strain sensors on a long-span suspension bridge in China.

  18. Field performance of timber bridges. 13, Mohawk Canal stress-laminated bridge

    Science.gov (United States)

    P. D. Hilbrich Lee; X. Lauderdale

    The Mohawk Canal bridge was constructed in August 1994, just outside Roll, Arizona. It is a simple-span, double-lane, stress-laminated deck superstructure, approximately 6.4 m (21 ft) long and 10.4 m (34 ft) wide and constructed with Combination 16F-V3 Douglas Fir glued-laminated timber beam laminations. The performance of the bridge was monitored continuously for 2...

  19. [Experiences with a subcutaneous, fully resorbable bridge in construction a double loop ileo- and colostomy].

    Science.gov (United States)

    Wedell, J; Banzhaf, G; Meier zu Eissen, P; Schlageter, M

    1990-01-01

    Our experience with the subcutaneous absorbable bridge for constructing a temporary loop ileostomy and loop colostomy is described. The use of this subcutaneous absorbable bridge in 15 patients - 6 with loop ileostomy and 9 with loop colostomy - was almost without complications. The absorbable bridge is a progress for maturation of the stoma and for immediate postoperative as prospective fitting of a watertight appliance. The actual trend substituting the temporary loop colostomy by the loop ileostomy may be advanced by the unlimited use of the subcutaneous absorbable bridge for constructing a temporary loop ileostomy.

  20. Sex Difference in Bottlenose Dolphin Sightings during a Long-term Bridge Construction Project

    OpenAIRE

    Ann Weaver

    2015-01-01

    Almost nothing is known about the effect of long-term bridge construction on free-ranging bottlenose dolphins (Tursiops truncatus). The species’ natural history predicts that there should be sex differences in reaction to construction because bottlenose dolphins show sex differences in most of their behaviors. A 5-year bridge construction project over a narrow but important dolphin corridor at John’s Pass tidal inlet, St. Petersburg FL, brought chronic environmental changes. The purpose of th...

  1. Failure of dental bridges. II. Prevalence of failure and its relation to place of construction.

    Science.gov (United States)

    Fayyad, M A; al-Rafee, M A

    1996-06-01

    In this investigation 156 dental bridges, constructed for 132 individuals, were evaluated. The bridges inserted at the College of Dentistry, King Saud University (KSU), Saudi Arabia, were compared with those placed in general dental practice. The results revealed that the rate of bridge failure averaged 35.5%. This was made up from failure of bridges inserted at KSU at (15.4%) and those in general dental practice (46.2%). The major reasons for failure revealed by this study were periodontal disease (36.6%) and secondary caries (23.2%). The average lifespan for the bridges was 6.1 years with 4.5 years for the unfailed bridges. The most commonly used material for bridges was metal-ceramics. The most commonly used pontic design was the modified ridge lap (50.8%), but the saddle type accounted for the greatest percentage of failures (59.6%).

  2. 33 CFR 165.T01-0176 - Regulated Navigation Area; Lake Champlain Bridge Construction, Crown Point, New York and Chimney...

    Science.gov (United States)

    2010-07-01

    ... Champlain Bridge Construction, Crown Point, New York and Chimney Point, Vermont. 165.T01-0176 Section 165...; Lake Champlain Bridge Construction, Crown Point, New York and Chimney Point, Vermont. (a) Description... and south of the Lake Champlain Bridge construction zone at Crown Point, New York and Chimney Point...

  3. Fatigue Life Assessment of Orthotropic Steel Deck with UHPC Pavement

    Directory of Open Access Journals (Sweden)

    Xu Jiang

    2017-01-01

    Full Text Available In recent years, a number of large-span bridges with orthotropic steel decks were constructed in China. With increasing traffic volumes and higher wheel loads, many fatigue cracks developed at the welds and the edge of cut-out holes. This paper aims at presenting the numerical analysis on the fatigue performance of the orthotropic steel deck using ultrahigh performance concrete (UHPC overlay as the deck pavement instead of the conventional asphalt concrete pavement. By using finite element method (FEM model, stress distribution at fatigue sensitive locations under the action of wheel loads is characterized and the obtained stress ranges indicate that the UHPC pavement significantly reduces the magnitude of the stress peak valued. A suggested truck stream model based on the weigh-in-motion (WIM data of four bridges in China is employed to calculate the stress variation at specific fatigue details. Furthermore, the fatigue damage accumulation at fatigue details under the UHPC and conventional asphalt concrete pavement is studied based on Miner’s linear cumulative damage rule and the rain-flow method. The results indicate that the UHPC pavement on the orthotropic steel deck can extend the service lives of the concerned regions over 100 years, but the fatigue lives will reduce significantly when the elastic modulus of UHPC decreases to 50% of the original value.

  4. [Development of the construction of adhesive bridges (Literature review)].

    Science.gov (United States)

    Tóth, P

    2001-08-01

    The author reviews the development of adhesive bridges since since the original publication of Rochette. The various abutment preparations (I., II. and III. generation) and the changing metal framework design is discussed in depth.

  5. Monolithic Concrete vs Precast Concrete for the Construction of Bridge by Th Cantilever Method

    Directory of Open Access Journals (Sweden)

    Morlova Dumitru Daniel

    2015-07-01

    Full Text Available In the article "Monolithic Concrete vs Precast Concrete for the Construction of Bridges by the Cantilever Method", there are approached a number of issues that come out in the design and execution of prestressed concrete bridge structures using the cantilever method.

  6. Standard Specifications for Construction of Roads and Bridges on Federal Highway Projects

    Science.gov (United States)

    1996-01-01

    These standard specifications were issued primarily for constructing roads and bridges on Federal Highway projects under the direct administration of the Federal Highway Administration. These specifications are cited as "FP-96" indicating Standard Sp...

  7. [Neuroscience and education: towards the construction of interactive bridges].

    Science.gov (United States)

    Benarós, Sol; Lipina, Sebastián J; Segretin, M Soledad; Hermida, M Julia; Jorge, Jorge A

    The debates on the potential interdisciplinary association between neuroscience and education began approximately three decades ago. In order for the integration of neuroscientific and educational knowledge to impact on learning and teaching it would imply the consideration of the emergence of several cognitive and emotional processes during development, and the possibility to influence them through specific interventions. AIM. To examine epistemological and methodological implications and bridging requirements in the interaction between neuroscience, cognitive psychology and education. A dynamic interdisciplinary bridging consists in the identification and reduction of different epistemological, methodological, technological and practical gaps between those disciplines. Furthermore, the consideration of complex phenomena, such as human development and learning processes in terms of multiple levels of analysis, may contribute to the enrichment of a critical dialogue, but also to generate genuine integrated interventions. Historical and current conceptual perspectives attempting to bridge neuroscience and education are described. At present, interdisciplinary efforts between neuroscience and education are at a preliminary stage. In this context, bridging requires conceptual and methodological approaches that consider the complexity of developmental and learning phenomena and the participation of actors from different fields, instead of unique bridges. This paper intends to consider several basic principles aimed at developing a dynamic integration that assesses the complexity of development, learning and teaching processes.

  8. Evaluation of a highway bridge constructed using high strength lightweight concrete bridge girders.

    Science.gov (United States)

    2011-04-01

    The use of high performance concretes to provide longer bridge spans has been limited due to the capacity of existing infrastructure to handle the load of the girders during transportation. The use of High Strength Lightweight Concrete (HSLW) can pro...

  9. Towards Sustainable Construction: Life Cycle Assessment of Railway Bridges

    DEFF Research Database (Denmark)

    Du, Guangli

    range of energy and raw materials consumptions, which is responsible for the most significant pollutions. However, current bridges are mainly designed by the criterion of economic, technique, and safety standards, while their correlated environmental burdens have unfortunately rarely been considered....... The life cycle assessment (LCA) method has been verified as a systematic tool, which enables the fully assessment and complete comparison for the environmental impact among different bridge options through a life cycle manner. The study presented in this thesis is focused on railway bridges, as the LCA...... implementation is under great expectations to set a new design criterion, to optimize the structural design towards the environmental sustainability, and to assist the decision-making among design proposals. This thesis consists of two parts: an extended summary and three appended papers. Part one gives...

  10. CONSTRUCTION THE BRIDGE PIER AS PARAMETRIC OBJECT USING AUTODESK REVIT

    Directory of Open Access Journals (Sweden)

    K. I. Hladka

    2017-08-01

    Full Text Available Purpose. The work is aimed to solve the following tasks: 1 to investigate the possibilities of Autodesk Revit to create parametric objects; 2 to create an information model of the bridge pier with the possibility of changing the model size without changing geometry of the object; 3 to trace the complexity and feasibility of using parametric models when designing the elements of bridges. Methodology. The studies were carried out using spatial modeling in the Autodesk Revit system. The ratio of the parameters of the object was set, the relationship between individual geometric elements was determined and the changes that were made to the model with the change of the specified parameters were checked. Findings. Support model of two types has been created: for railway bridges and for road bridges. Both types of models change the dimensions and the number of constituent elements in accordance with the entered parameters. The performed work confirms the possibility of creating information parametric models of complex form and the expediency of using them in the design of bridges and not only. Originality. Creation of information models is a modern and relevant topic. But both in the literature and in Internet resources, parametrization is considered on the example of simple objects. The model proposed in the article consists of several dependent geometric bodies; therefore, it opens the topic of objects parameterization more fully and in detail, in comparison with the existing sources. As for the creation of parametric models of the bridge elements - such information is not found in the literature, that is, it is proposed for the first time. Practical value. Parametrization of spatial models allows significantly to accelerate and simplify the process of designing any objects due to the use of typical parametric models in many projects. Especially it concerns the design of bridges, since the standard elements for them, such as support or span are not

  11. Problems of lamella flanges in steel bridge construction

    Czech Academy of Sciences Publication Activity Database

    Křístek, V.; Škaloud, Miroslav; Urushadze, Shota; Kunrt, J.

    2016-01-01

    Roč. 59, č. 1 (2016), s. 11-15 ISSN 2217-8139 R&D Projects: GA ČR(CZ) GA15-01035S Institutional support: RVO:68378297 Keywords : bridges * lamella flanges * repeated loading * breathing * limit states Subject RIV: JM - Building Engineering http://scindeks-clanci.ceon.rs/data/pdf/0543-0798/2016/0543-07981601011K.pdf

  12. 19 CFR 123.18 - Equipment and materials for constructing bridges or tunnels between the United States and Canada...

    Science.gov (United States)

    2010-04-01

    ... bridges or tunnels between the United States and Canada or Mexico. (a) Admission of equipment and materials. Equipment for use in construction of bridges or tunnels between the United States and Canada or... 19 Customs Duties 1 2010-04-01 2010-04-01 false Equipment and materials for constructing bridges...

  13. Sex Difference in Bottlenose Dolphin Sightings during a Long-term Bridge Construction Project

    Directory of Open Access Journals (Sweden)

    Ann Weaver

    2015-02-01

    Full Text Available Almost nothing is known about the effect of long-term bridge construction on free-ranging bottlenose dolphins (Tursiops truncatus. The species’ natural history predicts that there should be sex differences in reaction to construction because bottlenose dolphins show sex differences in most of their behaviors. A 5-year bridge construction project over a narrow but important dolphin corridor at John’s Pass tidal inlet, St. Petersburg FL, brought chronic environmental changes. The purpose of this 8-year study was to determine if bridge construction was associated with changes in dolphin sightings. The sex difference hypothesis was tested with a comparison of sighting probabilities before, during and after bridge construction. Sighting probabilities were generated for 68 adults seen n = 6504 times during N = 951 small-boat surveys of the 6.5-mile estuarine study area, documented with photo identification June 2005-December 2012. The sex difference hypothesis was supported with a significant interaction between construction and gender. Female sightings showed a significant linear decline across construction. Male sightings did not change across construction. The main conclusion is that adult males and females may react differently to habitat changes associated with anthropogenic activities. Sex differences in environmental monitoring and vigilance associated with maternal behavior may have played a role. This is the first report on John’s Pass dolphins that evaluates changes in their behavior during a major construction project across a narrow but important dolphin corridor.

  14. 77 FR 1407 - Regulated Navigation Area; Memorial Bridge Construction, Piscataqua River, Portsmouth, NH

    Science.gov (United States)

    2012-01-10

    ... like to know that they reached the Facility, please enclose a stamped, self-addressed postcard or..., and wake from passing vessels could pose significant risk of injury or death to construction workers... speed and wake of all vessels operating in the vicinity of the bridge construction zone. This will be...

  15. Environmental life cycle assessment of railway bridge materials using UHPFRC

    Directory of Open Access Journals (Sweden)

    Bizjak Karmen Fifer

    2016-10-01

    Full Text Available The railway infrastructure is a very important component of the world’s total transportation network. Investment in its construction and maintenance is significant on a global scale. Previously published life cycle assessment (LCA studies performed on road and rail systems very seldom included infrastructures in detail, mainly choosing to focus on vehicle manufacturing and fuel consumption. This article presents results from an environmental study for railway steel bridge materials for the demonstration case of the Buna Bridge in Croatia. The goal of these analyses was to compare two different types of remediation works for railway bridges with different materials and construction types. In the first part, the environmental impact of the classical concrete bridge construction was calculated, whereas in the second one, an alternative new solution, namely, the strengthening of the old steel bridge with ultra-high-performance fibre-reinforced concrete (UHPFRC deck, was studied. The results of the LCA show that the new solution with UHPFRC deck gives much better environmental performance. Up to now, results of LCA of railway open lines, railway bridges and tunnels have been published, but detailed analyses of the new solution with UHPFRC deck above the old bridge have not previously been performed.

  16. Optimizing rib width to height and rib spacing to deck plate thickness ratios in orthotropic decks

    Directory of Open Access Journals (Sweden)

    Abdullah Fettahoglu

    2016-12-01

    Full Text Available Orthotropic decks are composed of deck plate, ribs, and cross-beams and are frequently used in industry to span long distances, due to their light structures and load carrying capacities. Trapezoidal ribs are broadly preferred as longitudinal stiffeners in design of orthotropic decks. They supply the required stiffness to the orthotropic deck in traffic direction. Trapezoidal ribs are chosen in industrial applications because of their high torsional and buckling rigidity, less material and welding needs. Rib width, height, spacing, thickness of deck plate are important parameters for designing of orthotropic decks. In the scope of this study, rib width to height and rib spacing to deck plate thickness ratios are assessed by means of the stresses developed under different ratios of these parameters. For this purpose a FE-model of orthotropic bridge is generated, which encompasses the entire bridge geometry and conforms to recommendations given in Eurocode 3 Part 2. Afterwards necessary FE-analyses are performed to reveal the stresses developed under different rib width to height and rib spacing to deck plate thickness ratios. Based on the results obtained in this study, recommendations regarding these ratios are provided for orthotropic steel decks occupying trapezoidal ribs.

  17. EvoDevo and niche construction: building bridges.

    Science.gov (United States)

    Laland, Kevin N; Odling-Smee, John; Gilbert, Scott F

    2008-11-15

    Evolutionary developmental biology and niche-construction theory have much in common, despite independent intellectual origins. Both place emphasis on the role of ontogenetic processes in evolution. The same historical events shaped them, and similar philosophical and sociological barriers hindered their respective advances. Both perspectives maintain that neo-Darwinism needs a theory of macroevolutionary variation and that such a theory can now be adduced from developmental biology. Some proponents of both EvoDevo and niche construction propose additional evolutionary mechanisms, and specify a key role for stable extra-genetic forms of inheritance. Similarly, proponents of each lay emphasis on "reciprocal causation" in the relationship between organism and environment. We illustrate here how EvoDevo and niche construction could gain "added value" from each other, and demonstrate how the niche-construction perspective potentially provides a useful conduit to integrate evolutionary and developmental biology. Copyright 2008 Wiley-Liss, Inc.

  18. Development of a Bridge Construction Live Load Analysis Guide

    Science.gov (United States)

    2012-12-01

    This project was sponsored through the Wisconsin Highway Research Program and its Structure Technical Oversight : Committee. The objective of this research was to develop a guide for the analysis of construction loads with and without : traffic live ...

  19. Membrane protection for steel stringer tops : Yaquina Bay Bridge, Newport, Oregon : construction report.

    Science.gov (United States)

    1980-10-01

    The experimental feature of this project was to evaluate the application and performance of Chevron Industrial Membrane applied to the tops of steel deck stringers and other similar members as corrosion protection in conjunction with the deck replace...

  20. Caisson disease during the construction of the Eads and Brooklyn Bridges: A review.

    Science.gov (United States)

    Butler, W P

    2004-01-01

    The Eads Bridge (St. Louis) and the Brooklyn Bridge (New York City) were testing grounds for caisson construction. These caissons were enormous compressed air boxes used to build riverine piers and abutments anchoring the bridges. Caisson meant faster and cheaper construction, but there was a hidden cost---caisson disease (decompression sickness). Within caissons, workers labored at pressures as high as 55 psig and caisson disease was common. This discourse is a brief history of the caisson, a brief discussion of the illness as viewed in the mid 1800's, and an abbreviated history of the Eads and Brooklyn Bridges. It also provides a detailed description and evaluation of the observations, countermeasures, and recommendations of Dr. Alphonse Jaminet, the Eads Bridge physician, and Dr. Andrew Smith, the Brooklyn Bridge physician, who published reports of their experience in 1871 and 1873, respectively. These and other primary sources permit a detailed examination of early caisson disease and Jaminet's and Smith's thinking also serve as good examples from which to study and learn.

  1. Feasibility and impact of Muara Bulian Bridge construction on the economy of Batang Hari Regency

    Directory of Open Access Journals (Sweden)

    Muhammad Safri

    2017-12-01

    Full Text Available This study aims to determine the impact of Muara Bulian bridge construction on the economy of Batang Hari Regency. The number of vehicles transporting goods (transport coal and CPO through the City of Muara Bulian has made congestion in the City of Muara Bulian. Therefore,  it takes a diversion of currents for freight vehicles sothey will not cross the city of  Muara Bulian. The scope of the research focused on the social and economic impacts of the bridge construction and the feasibility study of the bridge financially. The type of data used is the type of secondary data obtained from interviews and data from related agencies in Jambi Province and Batang Hari Regency in 2016. Based on the results of the research, it is found that: (1 Construction of Muara Bulian Bridge is intended to build isolated areas in the Maro Sebo Ilir Subdistrict. Maro Sebo Ilir Subdistrict has enormous potential in terms of both plantations and mining. Potential plantations in Maro Sebo Ilir Subdistrict are oil palm and rubber while for mining there is coal and oil. The construction of the Muara Bulian bridge is expected to create new economic growth centers in Batang Hari Regency and can increase the strength and opportunities of new business potentials that have not existed in Batang Hari Regency, and (2 road connectivity on the north of the Muara Bulian bridge will be connected to an existing provincial road. To facilitate the flow of transportation to the provincial road, it is necessary to create a new road along ± 3 km with an estimated cost of ± Rp. 8,400,000,000 with standard cost 2,800,000,000 /km. Keywords: Financial feasibility, regional economy, socio-economic impact

  2. 75 FR 22228 - Regulated Navigation Area; Lake Champlain Bridge Construction Zone, NY and VT

    Science.gov (United States)

    2010-04-28

    ... would like to know that they reached the Facility, please enclose a stamped, self-addressed postcard or... to water movement, and wake from passing vessels could pose significant risk of injury or death to... limit vessel speed and wake of all vessels operating in the vicinity of the bridge construction zone...

  3. THE CONSTRUCTIVE SOLUTION AND CALCULATION OF ELEMENTS OF THE UNIFIED MODULE OF THE MOBILE BRIDGE OVERCROSSING

    Directory of Open Access Journals (Sweden)

    Adil KADYROV

    2017-09-01

    Full Text Available In the article the construction of a modular mobile overcrossing is offered. Calculation of its constructive elements is performed and the optimum length of one module is determined. The purpose is the development of the technique and calculation for the new construction of a mobile bridge overcrossing intended for reduction of traffic jams. Methods: The methods uses are mathematical analysis, method of finite elements, method of finite differences, and analytical method of relocation. Dependencies for determination of the optimum length of the module of bridge overcrossing are identified. The calculation of the constructive-orthotropic plate for the carriageway of the bridge overcrossing using numerical methods of finite differences and finite elements is performed; the reliability of results is confirmed with coincidence of deflection values. The solution matrix of the method of finite differences developed in this work allows calculation of arbitrary plates with a wide variety of geometrical sizes, and also for different values of flexural stiffness properties of the plate and reinforcing elements. The calculation of the spatial frame of the bridge overcrossing is performed by the precise analytical method of relocation taking into account the bend and torsion of its elements.

  4. Learning Based on the Project Entitled "Design and Construction of a Wooden Bridge"

    Science.gov (United States)

    Barris, Cristina; Torres, Lluís; Simon, Enric

    2016-01-01

    This article presents the results of a case involving the application of project-based learning carried out with students in the Mechanical Engineering degree program at the University of Girona. The project, entitled "Design and construction of a wooden bridge", was conducted at the Polytechnic School in the third-year Structures…

  5. Seismic Performance of Columns with Grouted Couplers in Idaho Accelerated Bridge Construction Applications

    Science.gov (United States)

    2016-10-16

    n Accelerated Bridge Construction (ABC) methods, one way to connect prefabricated columns is by using grouted steel bar couplers. As of October 2016, in the U.S., only Utah DOT allows the use of grouted couplers in plastic hinge locations in seismic ...

  6. Stress-corrosion susceptibility of highway bridge construction steels. Phase I

    Science.gov (United States)

    1972-04-01

    A catalog of steels used in highway bridge construction has been developed. A state-of-the-art survey on the stress-corrosion susceptibility of these steels has been conducted. The types and concentrations of corrosives that can be experienced in the...

  7. 23 CFR 661.41 - After a bridge project has been completed (either PE or construction) what happens with the...

    Science.gov (United States)

    2010-04-01

    ... PROGRAM § 661.41 After a bridge project has been completed (either PE or construction) what happens with... 23 Highways 1 2010-04-01 2010-04-01 false After a bridge project has been completed (either PE or construction) what happens with the excess or surplus funding? 661.41 Section 661.41 Highways FEDERAL HIGHWAY...

  8. THE SIMULATION DIAGNOSTIC METHODS AND REGENERATION WAYS OF REINFORCED - CONCRETE CONSTRUCTIONS OF BRIDGES IN PROVIDING THEIR OPERATING RELIABILITY AND LONGEVITY

    Directory of Open Access Journals (Sweden)

    B. V. Savchinskiy

    2010-03-01

    Full Text Available On the basis of analysis of existing diagnostic methods and regeneration ways of reinforced-concrete constructions of bridges the recommendations on introduction of new modern technologies of renewal of reinforced-concrete constructions of bridges in providing their operating reliability and longevity are offered.

  9. 46 CFR 190.10-45 - Weather deck communications.

    Science.gov (United States)

    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. ...

  10. Determining the Environmental Benefits of Ultra High Performance Concrete as a Bridge Construction Material

    Science.gov (United States)

    Lande Larsen, Ingrid; Granseth Aasbakken, Ida; O'Born, Reyn; Vertes, Katalin; Terje Thorstensen, Rein

    2017-10-01

    Ultra High Performance Concrete (UHPC) is a material that is attracting attention in the construction industry due to the high mechanical strength and durability, leading to structures having low maintenance requirements. The production of UHPC, however, has generally higher environmental impact than normal strength concrete due to the increased demand of cement required in the concrete mix. What is still not sufficiently investigated, is if the longer lifetime, slimmer construction and lower maintenance requirements lead to a net environmental benefit compared to standard concrete bridge design. This study utilizes life cycle assessment (LCA) to determine the lifetime impacts of two comparable highway crossing footbridges spanning 40 meters, designed respectively with UHPC and normal strength concrete. The results of the study show that UHPC is an effective material for reducing lifetime emissions from construction and maintenance of long lasting infrastructure, as the UHPC design outperforms the normal strength concrete bridge in most impact categories.

  11. Nonlinear Stability Analysis of a Composite Girder Cable-Stayed Bridge with Three Pylons during Construction

    Directory of Open Access Journals (Sweden)

    Xiaoguang Deng

    2015-01-01

    Full Text Available Based on the nonlinear stability analysis method, the 3D nonlinear finite element model of a composite girder cable-stayed bridge with three pylons is established to research the effect of factors including geometric nonlinearity, material nonlinearity, static wind load, and unbalanced construction load on the structural stability during construction. Besides, the structural nonlinear stability in different construction schemes and the determination of temporary pier position are also studied. The nonlinear stability safety factors are calculated to demonstrate the rationality and safety of construction schemes. The results show that the nonlinear stability safety factors of this bridge during construction meet the design requirement and the minimum value occurs in the maximum double cantilever stage. Besides, the nonlinear stability of the structure in the side of edge-pylon meets the design requirement in the two construction schemes. Furthermore, the temporary pier can improve the structure stability, effectively, and the actual position is reasonable. In addition, the local buckling of steel girder occurs earlier than overall instability under load in some cable tension stages. Finally, static wind load and the unbalanced construction load should be considered in the stability analysis for the adverse impact.

  12. Grey cast iron as construction material of bridges from the 18th and 19th century

    Directory of Open Access Journals (Sweden)

    J. Rabiega

    2011-04-01

    Full Text Available Many bridges and railroad viaducts, which have been operated at the western and southern regions of Poland, were erected at the end ofthe 18th or beginning of the 19th century. In recent years they undergo overhauls and renovations requiring familiarity with the construction materials they have been made of. It is necessary for estimation of their load capacity (possible reinforcements and determining their suitability for further utilisation. Among the materials in the old bridges the puddled steels and cast irons predominate. Aim of the work is identification and documentation of microstructure and selected properties of the cast irons used for production of parts for the bridge in Łażany, the Old Mieszczański Bridge in Wrocław, the hanging bridge in Ozimek, as well as the columnar piers of the railroad viaduct in Wrocław. Using the methods of light microscopy and scanning electron microscopy, as well as the results of hardness measurements and chemical analysis, it has been shown that the objects have been built of grey cast iron with flake graphite having the ferritic-pearlitic or pearlitic matrix. The diversification of their chemical analysis resulting from the type, size and geometry of the cast parts was indicated.The tested materials fulfil requirements of the contemporary standards related to grey cast irons of the EN-GJL-100 and EN-GJL-150grades.

  13. Elimination of deck joints using a corrosion resistant FRP approach.

    Science.gov (United States)

    2009-09-01

    The research presented herein describes the development of durable link slabs for jointless bridge decks based on using a fiber reinforced polymer (FRP) grid for reinforcement. Specifically the ductility of the FRP material was utilized to accommodat...

  14. Implementation of precast concrete deck system NUDECK (2nd generation).

    Science.gov (United States)

    2013-12-01

    The first generation of precast concrete deck system, NUDECK, developed by the University of NebraskaLincoln (UNL) for Nebraska Department of Roads (NDOR), was implemented on the Skyline Bridge, : Omaha, NE in 2004. The project was highly successful ...

  15. 46 CFR 116.1120 - Drainage of cockpit vessels, well deck vessels, and open boats.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Drainage of cockpit vessels, well deck vessels, and open... PASSENGERS CONSTRUCTION AND ARRANGEMENT Drainage and Watertight Integrity of Weather Decks § 116.1120 Drainage of cockpit vessels, well deck vessels, and open boats. Drainage of cockpit vessels, well deck...

  16. Durability of Materials in Pearl-Chain Bridges

    DEFF Research Database (Denmark)

    Lund, Mia Schou Møller

    This PhD thesis contributes to documentation regarding durability of materials used in so-called “Pearl-Chain Bridges”. The Pearl-Chain Bridge technology is a new precast bridge solution developed at the Technical University of Denmark. The technology reintroduces the arch structure...... as an economical beneficial solution primarily for road and railway bridges, and allows for the faster, more environmentally friendly, and cheaper construction of such bridges. A Pearl-Chain Bridge consists of two main parts: the load-carrying Pearl-Chain arch, and the fill material on top of the arch....... The construction of the Pearl-Chain arch is simple. The arch is assembled on its side, next to the road that the bridge will span, by placing a number of plane prefabricated Super-Light Decks that consist of lightweight aggregate concrete and conventional concrete, in the desired arch shape. Mortar joints are cast...

  17. [Influence of the prosthodontic construction on the marginal gingiva nearby dental crowns and bridges].

    Science.gov (United States)

    Tadumadze, L

    2005-09-01

    Along with the functional and aesthetic results, prosthodontic constructions must correspond to biological needs as well. They don't have to irritate the periodontal tissue, alveolar bone and gingiva. The aim of the study was to investigate gingival status under modified artificial teeth using cytomorphology (PAP) methods. Cytological investigations were carried out in 30 patients. 19 of them were using modified crowns and 11--modified bridges. Gingival status was marked using CD I and II indexes. Cytomorphometric investigations showed that modified prosthodontic constructions do not harm gingivas which are under the modification. Dynamic cytological changes found at the time of treatment represent individual biological reaction to the artificial teeth.

  18. To the rationalization of the constructive solutions of the bridge supports

    Directory of Open Access Journals (Sweden)

    Petrova Olena

    2017-01-01

    Full Text Available Reduction of material consumption and labor intensity of building structures is a topical task for both theory and practice of building production. Today there are many ways to achieve proper economic effect while reconstruction or erection of building and structures. One of them is to rationalize well-known constructive solutions using as criteria the value of density of potential energy of deformation of structures. In this connection, the new constructive solution for short massive supports with outer reinforcement made of expanded metal sheet and frames (reinforcing rings which are used in construction of road and railway bridges and high-rise buildings is proposed in this paper. The theoretical approach for the definition of its rational parameters is given. Numerical analysis of the highlighted method is also carried out. As a result of study the increase in the bearing capacity in concrete pillars made in rational mesh clips with and without frames was obtained.

  19. Reliability-based failure cause assessment of collapsed bridge during construction

    International Nuclear Information System (INIS)

    Choi, Hyun-Ho; Lee, Sang-Yoon; Choi, Il-Yoon; Cho, Hyo-Nam; Mahadevan, Sankaran

    2006-01-01

    Until now, in many forensic reports, the failure cause assessments are usually carried out by a deterministic approach so far. However, it may be possible for the forensic investigation to lead to unreasonable results far from the real collapse scenario, because the deterministic approach does not systematically take into account any information on the uncertainties involved in the failures of structures. Reliability-based failure cause assessment (reliability-based forensic engineering) methodology is developed which can incorporate the uncertainties involved in structural failures and structures, and to apply them to the collapsed bridge in order to identify the most critical failure scenario and find the cause that triggered the bridge collapse. Moreover, to save the time and cost of evaluation, an algorithm of automated event tree analysis (ETA) is proposed and possible to automatically calculate the failure probabilities of the failure events and the occurrence probabilities of failure scenarios. Also, for reliability analysis, uncertainties are estimated more reasonably by using the Bayesian approach based on the experimental laboratory testing data in the forensic report. For the applicability, the proposed approach is applied to the Hang-ju Grand Bridge, which collapsed during construction, and compared with deterministic approach

  20. Role to Be Played by Independent Geotechnical Supervision in the Foundation for Bridge Construction

    Science.gov (United States)

    Sobala, Dariusz; Rybak, Jarosław

    2017-10-01

    Some remarks concerning the necessity of employing an independent and over all ethical geotechnical survey were presented in the paper. Starting from the design phase, through the whole construction process, the importance of geotechnical engineer is stated in legal acts. Numerous testing technologies serve for the calibration of geotechnical technologies and allow for confirming the quality and capacity of piles. Special emphasis was payed to the involvement of scientifical and research institutions which can not only serve services but also can postprocess and methodize collected data. Such databases enable for new codes, methods and recommendations. Selection of deep foundations for bridge-type structures is most often dependent on complex geotechnical conditions, concentrated loads and constraints for pier displacements. Besides the last ones, prior to more common introduction of the design-construct system, could be a convenient justification for design engineer, who imposed deep foundation because he did not want or was not able to estimate the effect of pier settlement on civil engineering structure. The paper provides some notes about the need to engage a geotechnical supervising service of high competency and ethical quality during engineering and construction stages of foundations for bridge-type structures where legal requirements are of special consideration. Successive stages of projects are reviewed and research methods used for current calibration of geotechnical technologies and verification of geotechnical work quality are analysed. Special attention is given to potential involvement of independent R&D institutions which, apart from rendering specific services, also collect and systemize the research results thus enabling, in the long term, to revise engineering standards, instructions and guidelines.

  1. Platform deck. Plattformdekk

    Energy Technology Data Exchange (ETDEWEB)

    Gudmestad, O.T.; Warland, T.Aa.; Coker, J.W.A.; Stead, B.

    1992-03-30

    The invention deals with a platform deck comprising a trusswork deck section and a deck section made of plates designed for being welded together for the final concreting. The deck structure is designed for being connected to at least two shafts, and can include equipment, needing protection against pollution, or natural ventilation systems. Each of the two sections mentioned can be built by different contractors and finally assembled onshore or offshore. Both of the sections are equipped with corresponding upper and lower supporting elements for simplifying the assembling procedure. 4 figs.

  2. Assessment of exposure pathways connected with construction and operation of concrete bridge reinforced with very low level radioactive steel

    International Nuclear Information System (INIS)

    Panik, M.; Necas, V.

    2012-01-01

    Large amount of low level radioactive material arises during decommissioning of nuclear power plants. Material mostly comprises metal scrap and concrete ruble. Paper deals with recycling and reuse of metal scrap and its utilization as part of reinforcement of concrete bridges under the conditional release concept. Radiation exposure originating in very low level reinforcement steel consists of several exposure pathways. Short-term radiation impact is represented mostly by external exposure pathway and it is relevant to the construction workers and users of the bridge. Long-term radiation impacts on inhabitants living near finished bridge and it is divided into inhalation and ingestion of radionuclides-internal exposure pathways. Radiation impact caused by utilization of very low level radioactive waste was calculated using simulation software VISIPLAN 3D ALARA and GOLDSIM. Results of calculations provide fair summary of possibilities of utilization of conditionally released steel as reinforcement of concrete bridges. (Authors)

  3. Damage detection based on mode shapes of a girder bridge constructed from responses of a moving vehicle under impact excitation

    Science.gov (United States)

    Qi, Zhongqiang; Au, Francis T. K.

    2016-04-01

    The vibration mode shapes are often used to identify damage of bridges because the mode shapes are not only important modal properties but also sensitive to damage. However, the key issue is how to conveniently obtain the mode shapes of a bridge in service. Traditional methods invariably require installation of instruments on the bridge for collection of dynamic responses for constructing mode shapes, which are both costly and inconvenient. Therefore a method is developed to construct the mode shapes of simply supported bridges based on Hilbert Transform using only vehicle acceleration response for identification of the location of damage. Firstly, an algorithm is devised to construct the mode shapes by using the dynamic responses extracted from a moving vehicle under impact excitation. Then, based on these intermediate results, the coordinate modal assurance criterion in conjunction with suitable wavelets is used to identify the location of damage. Compared with the traditional methods, the proposed method uses only the information from the moving vehicle. Moreover, additional impact excitation on the vehicle helps to excite the bridge. This helps to improve the accuracy by overcoming the adverse effects of measurement noise and road surface roughness, which leads to high accuracy of damage detection. To verify the feasibility of the proposed method, some numerical studies have been carried out to investigate the effects of measurement noise, road surface roughness and multiple locations of damage on the accuracy of results.

  4. Improvement of fatigue properties of orthotropic decks

    Czech Academy of Sciences Publication Activity Database

    Frýba, Ladislav; Urushadze, Shota

    2011-01-01

    Roč. 33, č. 4 (2011), s. 1166-1169 ISSN 0141-0296 R&D Projects: GA ČR GA103/08/1340; GA MŠk(CZ) 7E08098 Grant - others:BRIFAG -Bridge Fatigue Guidance(XE) RFSR_CT-2008-00033 Institutional research plan: CEZ:AV0Z20710524 Keywords : orthotropic deck * fatigue * prolonged life Subject RIV: JM - Building Engineering Impact factor: 1.351, year: 2011

  5. 46 CFR 92.10-45 - Weather deck communications.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Weather deck communications. 92.10-45 Section 92.10-45 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS CONSTRUCTION AND ARRANGEMENT Means of Escape § 92.10-45 Weather deck communications. (a) Vertical communication...

  6. Rapid construction of Pacific Street Bridge with o.7 inch strands.

    Science.gov (United States)

    2010-10-01

    The Pacific Street Bridge over I-680 in Omaha, NE is the first bridge in the United States to use 0.7-in.-diameter prestressing : strands in pretensioned concrete girders. This project was funded by FHWA through NDOR under the Innovative Bridge Resea...

  7. Design and construction of the lawnmower, an artificial burnt-bridges motor.

    Science.gov (United States)

    Kovacic, Suzana; Samii, Laleh; Curmi, Paul M G; Linke, Heiner; Zuckermann, Martin J; Forde, Nancy R

    2015-04-01

    Molecular motors of the cell are protein-based, nanoscale machines, which use a variety of strategies to transduce chemical energy into mechanical work in the presence of a large thermal background. The design and construction of artificial molecular motors is one approach to better understand their basic physical principles. Here, we propose the concept of a protein-based, burnt-bridges ratchet, inspired by biological examples. Our concept, the lawnmower, utilizes protease blades to cleave peptide substrates, and uses the asymmetric substrate-product interface arising from productive cleavage to bias subsequent diffusion on the track (lawn). Following experimental screening to select a protease to act as the motor's blades, we chemically couple trypsin to quantum dots and demonstrate activity of the resulting lawnmower construct in solution. Accompanying Brownian dynamics simulations illustrate the importance for processivity of correct protease density on the quantum dot and spacing of substrates on the track. These results lay the groundwork for future tests of the protein-based lawnmower's motor performance characteristics.

  8. Construction

    Science.gov (United States)

    2002-01-01

    Harbor Deepening Project, Jacksonville, FL Palm Valley Bridge Project, Jacksonville, FL Rotary Club of San Juan, San Juan, PR Tren Urbano Subway...David. What is nanotechnology? What are its implications for construction?, Foresight/CRISP Workshop on Nanotechnology, Royal Society of Arts

  9. Evaluation of external exposure during building and operation of concrete bridges constructions that reuse the conditionally released steels - 59120

    International Nuclear Information System (INIS)

    Panik, Michal; Necas, Vladimir

    2012-01-01

    This paper presents ongoing results of the project presented at ICEM'10 [1] related to the topics of reusing the conditionally released materials from decommissioning. The subject of the reuse of conditionally released materials in this case is modeling of bridge constructions which reuse the conditionally released steel in the form of reinforcement bars for the concrete bridges. A general approach for the project was presented at ICEM'10. The activities of the project continue in evaluating the individual effective doses from the external exposure based on reused conditionally released steels separately for public and for professionals (the internal exposure will be evaluated in next stages of the project). Evaluated scenarios are related to critical groups of professionals constructing the bridges (worker's scenarios). The computer code VISIPLAN 3D ALARA 4.0 planning tool was used for the calculation of the individual effective dose for professionals. Various limits of the annual individual effective dose are used for the evaluation of calculation results. The aim of the ongoing modeling is to develop a set of data of maximal radioactivity concentration for individual radionuclides in the conditionally released steel used in the bridges model constructions in order not to exceed the limits for the individual effective dose. (authors)

  10. Analysis of the embodied energy and the CO2 emission in construction process of a bridge structure from the aspect of sustainability

    Directory of Open Access Journals (Sweden)

    Čokić Miloš

    2015-01-01

    Full Text Available This paper presents a comparative analysis of embodied energy and CO2 emission, in the construction process of three bridge structures. Analyzed structures are prestressed concrete bridges with different structural systems and a total length of 88 meters. The correlation of structural system, construction method, material quantities and embodied energy and CO2 emission were considered. Influence of the selected solutions in main steps of design and construction on the energy consumption and the emission of CO2 is presented. The results should provide a better understanding of the effects of certain factors, in the bridge construction process, and their impact on the environment.

  11. Development and layout of a protocol for the field performance of concrete deck and crack sealers.

    Science.gov (United States)

    2009-09-01

    The main objective of this project was to develop and layout a protocol for the long-term monitoring and assessment of the performance of concrete deck and crack sealants in the field. To accomplish this goal, a total of six bridge decks were chosen ...

  12. Risk management analysis for construction of Kutai Kartanegara bridge-East Kalimantan-Indonesia

    Science.gov (United States)

    Azis, Subandiyah

    2017-11-01

    Many sources of risk that may impede the achievement of the project objectives through either cost or quality and time, especially for bridges that have collapsed before, so when the implementation of possible hazard / high hazard so when should the possible hazard/high hazard be implemented The purpose of this research is to identify, to analyze risks by classifying the risks using the method of Risk Breakdown Structure (RBS) and managing the dominant risk of execution of the installation work to determine the handling of the steel frame in order to maximize the positive and minimize the incidence of adverse events. The results of this study indicate there are 15 sources of risks are identified, and there are 6 risk indicates the dominant risks. Mitigation performed on the dominant risks unacceptable i.e. Project factor that shows the delays in the arrival of materials due to locations, schedule of the arrival of materials should be tailored to the needs of the field and the amount of material that comes with the required field should also be evaluated. The result is expected to be a guideline for identifying risks and mitigation measures for further research. Subsequent researchers to pay attention on the security factor that implementation time does not affect the productivity of work in construction projects.

  13. Food-Bridging: A New Network Construction to Unveil the Principles of Cooking

    Directory of Open Access Journals (Sweden)

    Tiago Simas

    2017-06-01

    Full Text Available In this manuscript, we propose, analyze, and discuss a possible new principle behind traditional cuisine: the Food-bridging hypothesis and its comparison with the food-pairing hypothesis using the same dataset and graphical models employed in the food-pairing study by Ahn et al. (2011. The Food-bridging hypothesis assumes that if two ingredients do not share a strong molecular or empirical affinity, they may become affine through a chain of pairwise affinities. That is, in a graphical model as employed by Ahn et al., a chain represents a path that joints the two ingredients, the shortest path represents the strongest pairwise chain of affinities between the two ingredients. Food-pairing and Food-bridging are different hypotheses that may describe possible mechanisms behind the recipes of traditional cuisines. Food-pairing intensifies flavor by mixing ingredients in a recipe with similar chemical compounds, and food-bridging smoothes contrast between ingredients. Both food-pairing and food-bridging are observed in traditional cuisines, as shown in this work. We observed four classes of cuisines according to food-pairing and food-bridging: (1 East Asian cuisines, at one extreme, tend to avoid food-pairing as well as food-bridging; and (4 Latin American cuisines, at the other extreme, follow both principles. For the two middle classes: (2 Southeastern Asian cuisines, avoid food-pairing and follow food-bridging; and (3 Western cuisines, follow food-pairing and avoid food-bridging.

  14. Design Optimization and Structural Performance Evaluation of Plate Girder Bridge Constructed Using a Turn-Over Process.

    Science.gov (United States)

    Eom, Gi-Ha; Kim, Sung Jae; Lee, Tae-Hee; Kim, Jang-Ho Jay

    2017-03-13

    A recent trend in bridge construction has been the optimization of the cost-to-performance ratio. The most effective way to optimize the cost-to-performance ratio is to maximize the efficiency of the superstructure. Currently, many bridge engineers and designers favor two- or three- girder plate superstructures, due to their cost advantages. However, research on the performance enhancements of the I-type girder in two- or three- girder plate bridges is lacking. One of the most important performance improvement technologies for the I-type girder is the "preflex" method. In the preflex method, the specimen is inverted during the construction process to apply prestressed cambering to the specimen by using self-weight. However, a problem with the preflex construction method is difficulty with inverting the girder/plate system during the concrete curing process. Therefore, a new inverting system called Turn-Over (TO) wheel was proposed. Using TO wheels, wider variations to the I-type girder design can be achieved. Using this TO construction method, various cross sectional designs of girder plate systems can be considered due to its easiness in inverting the girder/plate system. In this study, the location of concrete confinement sections between the steel I-beams and concrete plates was varied in an I-girder cross-sectional design. Design parameters included effective height, flange thickness, flange width, confining concrete section width, etc. From this study, the optimum cross-sectional design of the I-girder/concrete plate system was achieved. Then, a single 20 m TO girder/plate system and two 20 m TO girder bridges were constructed and tested to evaluate their performance. From the test, failure behavior, load carrying capacity, crack pattern, etc., are obtained. The results are discussed in detail in this paper.

  15. Design Optimization and Structural Performance Evaluation of Plate Girder Bridge Constructed Using a Turn-Over Process

    Directory of Open Access Journals (Sweden)

    Gi-Ha Eom

    2017-03-01

    Full Text Available A recent trend in bridge construction has been the optimization of the cost-to-performance ratio. The most effective way to optimize the cost-to-performance ratio is to maximize the efficiency of the superstructure. Currently, many bridge engineers and designers favor two- or three- girder plate superstructures, due to their cost advantages. However, research on the performance enhancements of the I-type girder in two- or three- girder plate bridges is lacking. One of the most important performance improvement technologies for the I-type girder is the “preflex” method. In the preflex method, the specimen is inverted during the construction process to apply prestressed cambering to the specimen by using self-weight. However, a problem with the preflex construction method is difficulty with inverting the girder/plate system during the concrete curing process. Therefore, a new inverting system called Turn-Over (TO wheel was proposed. Using TO wheels, wider variations to the I-type girder design can be achieved. Using this TO construction method, various cross sectional designs of girder plate systems can be considered due to its easiness in inverting the girder/plate system. In this study, the location of concrete confinement sections between the steel I-beams and concrete plates was varied in an I-girder cross-sectional design. Design parameters included effective height, flange thickness, flange width, confining concrete section width, etc. From this study, the optimum cross-sectional design of the I-girder/concrete plate system was achieved. Then, a single 20 m TO girder/plate system and two 20 m TO girder bridges were constructed and tested to evaluate their performance. From the test, failure behavior, load carrying capacity, crack pattern, etc., are obtained. The results are discussed in detail in this paper.

  16. 78 FR 12260 - Regulated Navigation Area-Weymouth Fore River, Fore River Bridge Construction, Weymouth and...

    Science.gov (United States)

    2013-02-22

    ... bridge will reach the end of its useable life span in 2018 and the Massachusetts Department of... temporary existing bridge spans. D. Regulatory Analyses We developed this proposed rule after considering... unforeseen, that could pose an imminent hazard to persons and vessels operating in the area. This rule is...

  17. Effects of ambient temperature changes on integral bridges.

    Science.gov (United States)

    2008-09-01

    Integral bridges (IBs) are jointless bridges whereby the deck is continuous and monolithic with abutment walls. IBs are outperforming their non-integral counterparts in economy and safety. Their principal advantages are derived from the absence of ex...

  18. Design and construction guidelines for strengthening bridges using fiber reinforced polymers (FRP).

    Science.gov (United States)

    2014-09-01

    This research concerns the development of guidelines : for the design and use of externally-bonded FRP : strengthening systems on bridges in Michigan. Si : x representative international FRP-related guidelines : were analyzed and compared for applica...

  19. Self-consolidating concrete for prestressed applications - phase II : bridge construction and in-place performance.

    Science.gov (United States)

    2015-04-01

    Prior to statewide acceptance of self-consolidating concrete (SCC) in precast, prestressed bridge member : production, the Alabama Department of Transportation sponsored an investigation of the material to be : performed by the Auburn University High...

  20. Design, construction and load testing of the Pat Daly road bridge in Washington County, MO, with internal glass fiber reinforced polymers reinforcement.

    Science.gov (United States)

    2013-01-01

    The overarching goal of this project is to deploy and assess an innovative corrosion-free bridge construction technology for long-term : performance of new and existing bridges. The research objective of this project is to conduct a comprehensive stu...

  1. Design, construction and load testing of the Pat Daly Bridge in Washington County, MO, with internal glass fiber reinforced polymers reinforcement.

    Science.gov (United States)

    2013-01-01

    The overarching goal of this project is to deploy and assess an innovative corrosion-free bridge construction technology for long-term : performance of new and existing bridges. The research objective of this project is to conduct a comprehensive stu...

  2. A-DECK, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — The technical objectives of A-DECK are: 1)Flight Weight including rideshare payloads will be less than 500 Kg. 2)First fundamental frequency of integrated A-DECK...

  3. Compressive Membrane Action in Prestressed Concrete Deck Slabs

    NARCIS (Netherlands)

    Amir, S.

    2014-01-01

    One of the most important questions that structural engineers all over the world are dealing with is the safety of the existing structures. In the Netherlands, there are a large number of transversely prestressed bridge decks that have been built in the last century and now need to be investigated

  4. Punching shear strength of transversely prestressed concrete decks

    NARCIS (Netherlands)

    Amir, S.; Van der Veen, C.; Walraven, J.C.

    2012-01-01

    In the Netherlands, there is a need to determine the capacity of bridge decks as a large number of them were built back in the 60’s and 70’s. Since then, not only a lot of additional safety requirements have been incorporated into the modern codes but the traffic flow has also increased drastically.

  5. Study of technology of pile foundation construction of no.5 main pier of Shoujiang bridge in Wenchuan County

    Science.gov (United States)

    Huang, Xianbin; Liu, Chenyang; Chen, Chunyang; Wangren, Yahong; Xu, Jialin; Xian, Jin

    2018-03-01

    The group of pile foundation of no.5 pier in Shoujiang Bridge needs to overcome the big load of large span continuous steel structure. The length of single pile foundation is 77m and the diameter of single pile foundation is 250cm. It not only faces the flood in the upstream of Shoujiang river, the construction obstacles during summer rain period, but also the reservoir clearance activity of Zipingpu reservoir and the high water level in winter and other water level fluctuation that have huge impact on platform of pile foundation construction. This article introduces the preparation in aspect of personnel, material, equipment and so on of pile foundation construction, and also conduct intensive research on leveling the field, assaying pile location, the embedment of the steel casing, installing the drill, mixing mud, drilling, final hole inspection and clearance, steel cage construction, perfusing concrete under water.

  6. Heat Storage Performance of the Prefabricated Hollow Core Concrete Deck Element with Integrated Microencapsulated Phase Change Material

    DEFF Research Database (Denmark)

    Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

    2012-01-01

    The paper presents the numerically calculated dynamic heat storage capacity of the prefabricated hollow core concrete deck element with and without microencapsulated phase change material (PCM). The reference deck is the ordinary deck made of standard concrete material and that is broadly used...... in many emerging buildings. The new concrete deck with microencapsulated PCM is the standard deck on which one more layer with PCM concrete was added and at the same time the latent heat storage was introduced to the construction. The challenge to simulate the performance of the new deck with PCM concrete...

  7. A profile of CCA-treated lumber removed from service in the southeastern United States decking market

    Science.gov (United States)

    Delton Alderman; Robert Smith; Philip A. Araman

    2003-01-01

    This research developed a profile of used chromated copper arsenate (CCA) lumber removed from the demolition of residential decking. This was achieved by gathering and compiling information regarding the construction, demolition, deck remodeling, deck replacement factors, and factors affecting the recovery of spent CCA lumber. In addition, qualitative responses...

  8. Fiber reinforced polymer composites for bridge structures

    Directory of Open Access Journals (Sweden)

    Alexandra CANTORIU

    2013-12-01

    Full Text Available Rapid advances in construction materials technology have led to the emergence of new materials with special properties, aiming at safety, economy and functionality of bridges structures. A class of structural materials which was originally developed many years ago, but recently caught the attention of engineers involved in the construction of bridges is fiber reinforced polymer composites. This paper provides an overview of fiber reinforced polymer composites used in bridge structures including types, properties, applications and future trends. The results of this study have revealed that this class of materials presents outstanding properties such as high specific strength, high fatigue and environmental resistance, lightweight, stiffness, magnetic transparency, highly cost-effective, and quick assembly, but in the same time high initial costs, lack of data on long-term field performance, low fire resistance. Fiber reinforced polymer composites were widely used in construction of different bridge structures such as: deck and tower, I-beams, tendons, cable stands and proved to be materials for future in this field.

  9. 78 FR 53668 - Regulated Navigation Area; Maine Kennebec Bridge Construction Zone, Kennebec River, Richmond, ME

    Science.gov (United States)

    2013-08-30

    ... to enforce speed and wake restrictions and prohibit all vessel traffic through the RNA during bridge..., suitable for copying and electronic filing. If you submit comments by mail and would like to know that they... of the Port Sector Northern New England (COTP) to establish speed and wake restrictions and to...

  10. Click construction of spiro- and bridged-quatrefoil polymer topologies with kyklo-telechelics having an azide group.

    Science.gov (United States)

    Ko, Yee Song; Yamamoto, Takuya; Tezuka, Yasuyuki

    2014-02-01

    Unprecedented tetracyclic polymer topologies with spiro- and a bridged-type quatrefoil forms are effectively constructed through an alkyne-azide, click-linking reaction by employing a kyklo-telechelic poly(tetrahydrofuran), poly(THF), precursor having an azide group, obtained through an electrostatic self-assembly and covalent fixation (ESA-CF) process, and complementary tetrafunctional alkyne reagents of either a pentaerythritol derivative or a four-armed star telechelic polymer precursor. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. New And Existing Bridge Constructions - Increase of Fatigue Strength of Welded Joints by High Frequency Mechanical Impact Treatment

    Directory of Open Access Journals (Sweden)

    Ummenhofer Thomas

    2013-07-01

    Full Text Available Numerous studies at KIT prove that high frequency mechanical impact (HFMI treatment is an efficient method for increasing the fatigue strength of welded steel structures. Within different research projects it was found that HFMI-methods can be used successfully for new and existing structures in order to extend the fatigue life. This paper gives an overview of the current status of existing steel bridges in Germany regarding aspects like bridge age distributions and traffic loads. Based on that overview welded joints susceptible to fatigue failure are identified. Using component-like small scale specimens, HFMI-methods were investigated within the objective of implementing an effective application for new and existing structures. Applying the fatigue test data observed, existing design proposals are evaluated and design recommendations for HFMI-treated joints are given. As a result of the research work, a transfer into practice has been realized and different applications are illustrated using the example of bridge constructions made of steel.

  12. Multi-parameter monitoring of the construction and evolution of a snow bridge over a crevasse on an Alpine glacier

    Science.gov (United States)

    Ravanel, Ludovic; Malet, Emmanuel; Batoux, Philippe

    2017-04-01

    Snow bridges that form over the crevasses of the Alpine glaciers allow mountaineers and skiers to cross them easily but constitute an important danger in case of rupture. Between 2008 and 2014, 37 injured persons and 13 deaths related to falls into crevasse were recorded (i.e. an average of two deaths per year) on the glaciers of the French side of the Mont Blanc massif - out of the famous Vallée Blanche ski route, which however embodies an important part of the aid related to falls into crevasses. To understand the construction and evolution of these fragile structures, instrumentation was set up on the Glacier du Géant, at 3450 m a.s.l., near the Aiguille du Midi (3842 m a.s.l.), on the French side of the Mont Blanc massif, close to a crevasse whose bridge had recently collapsed over a length of 37 m. The maximum width of the crevasse in this area is 6 m. At the top of a 7-m-high pole - to prevent future snowfalls -, sensors have been installed in September 2016 to measure different snow and weather parameters: air temperature, wind speed and direction, snow height. An automatic camera surveys the crevasse and the snow bridge geometry. Several other sensors monitor the temperature of snow and air in the crevasse. In addition, an extensometer was installed into the crevasse to measure the evolution of its width. The results of the first 6 months of survey are presented, including the formation of the bridge in mid-November, during a period of snowfall associated with a strong wind. Although the instrumentation is well suited to the high mountain conditions, its maintenance is delicate due to the strong instability of the environment (glacier movements and extreme weather conditions, primarily) but the results of this work will bring new glaciological knowledges which should participate in a better safety on glaciers.

  13. An innovative steel-concrete joint for integral abutment bridges

    Directory of Open Access Journals (Sweden)

    Bruno Briseghella

    2015-08-01

    Full Text Available Integral abutment bridges are becoming rather common, due to the durability problems of bearings and expansion joints. At the same time, among short- and medium-span bridges, multi-beam steel-concrete composite deck with hot-rolled girder is an economical and interesting alternative to traditional pre-stressed concrete solutions. The two concepts can be linked together to design integral steel-concrete composite bridges with the benefits of two typologies. The most critical aspect for these bridges is usually the joints between deck and piers or abutments. In this paper, an innovative beam-to-pier joint is proposed and a theoretical and experimental study is introduced and discussed. The analyzed connection is aimed at combining general ease of construction with a highly simplified assembly procedure and a good transmission of hogging and sagging moment at the supports in continuous beams. For this purpose, the traditional shear studs, used at the interface between steel beam and upper concrete slab, are also used at the ends of steel profiles welded horizontally to the end plates. To better understand the behaviour of this kind of joints and the roles played by different components, three large-scale specimens were tested and an FE model was implemented. The theoretical and experimental results confirmed the potential of the proposed connection for practical applications and indicated the way to improve its structural behaviour.

  14. Numerical investigation of the bearing capacity of transversely prestressed concrete deck slabs

    NARCIS (Netherlands)

    Amir, S.; Van der Veen, C.; Walraven, J.C.; De Boer, A.

    2014-01-01

    The research subject of this paper is the bearing capacity of transversely prestressed concrete bridge decks between concrete girders under concentrated loads. Experiments on a 1:2 scale model of this bridge were carried out in the laboratory and a 3D nonlinear finite element model was developed in

  15. History of the West Seattle Bridge; a Unique Alliance in Construction Management.

    Science.gov (United States)

    1988-01-01

    startup at the bridge would coincide with the scale-down at Chief Joseph Dam. Pointing to this benefit and the fact that the District was involved in...Corps procedures, however, a listing of payable quantities on each contract drawing was also required. The benefits of such tedious cataloging was...hi3 i h l acaI ha CL. him W al 30 a@ 10 0 IL01 10010 o 13 OC "a. .00U~ 09 -I -a- c-U -- U U ~ U ~ ~ U ha U a ccc zZ c Uz 0 0 0- W l oa hi ou "- c. 0

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

    Science.gov (United States)

    Wagner, Chad; Fitzgerald, Sharon; Lauffer, Matthew

    2015-01-01

    The presentation will provide an overview of a collaborative study between USGS, NC Department of Transportation and URS Corporation to characterize stormwater runoff from bridges in North Carolina and the effects of bridge runoff on receiving streams. This investigation measured bridge deck runoff from 15 bridges for 12-15 storms, stream water-quality data for baseflow and storm conditions at four of the bridge deck sites and streambed sediment chemistry upstream and downstream of 30 bridges across North Carolina. Background on why the study was conducted, objectives and scope and a general summary of the major results and conclusions will be presented.

  17. Developing improved opportunities for the recycling and reuse of materials in road, bridge, and construction projects.

    Science.gov (United States)

    2014-12-01

    The use of recycled and reused materials in transportation construction reduces consumption of non-renewable : resources. The objective of this research was to develop opportunities for improving the recycling and reuse of : materials in road and bri...

  18. Construction Planning of a Railway Bridge Using the Concept of 4D BIM

    OpenAIRE

    Dirweesh, Salah Aldein M.

    2015-01-01

    Between the world industries and in the slight past decades the market of the Architecture, Engineering, and Construction (AEC) industry was decreasing from a quality of producing and execution point of view. A new rising concept appears lately to help in solving this dilemma, Building Information Modeling (BIM) was that concept with the new dimensions methods. The fourth BIM dimensions (4D BIM) is used for the method of this research to monitor and control the construction processes with the...

  19. Characterization of water-quality and bed-sediment conditions in Currituck Sound, North Carolina, prior to the Mid-Currituck Bridge construction, 2011–15

    Science.gov (United States)

    Wagner, Chad R.; Fitzgerald, Sharon; Antolino, Dominick J.

    2015-12-24

    The North Carolina Turnpike Authority, a division of the North Carolina Department of Transportation, is planning to make transportation improvements in the Currituck Sound area by constructing a two-lane bridge from U.S. Highway 158 just south of Coinjock, North Carolina, to State Highway 12 on the Outer Banks just south of Corolla, North Carolina. The results of the Final Environmental Impact Study associated with the bridge and existing roadway improvements indicated potential water-quality and habitat impacts to Currituck Sound related to stormwater runoff, altered light levels, introduction of piles as hard substrate, and localized turbidity and siltation during construction.

  20. Construction of double-stranded metallosupramolecular polymers with a controlled helicity by combination of salt bridges and metal coordination.

    Science.gov (United States)

    Ikeda, Masato; Tanaka, Yoshie; Hasegawa, Takashi; Furusho, Yoshio; Yashima, Eiji

    2006-05-31

    We describe the construction of the first double-stranded metallosupramolecular helical polymers. We designed and synthesized a supramolecular duplex comprised of complementary m-terphenyl-based strands bearing a chiral amidine or achiral carboxylic acid together with two pyridine groups at the four ends. Supramolecular polymerization of the duplex with cis-PtPh2(DMSO)2 in 1,1,2,2-tetrachloroethane produced the double-stranded metallosupramolecular polymer with a controlled helicity of which the two complementary metallostrands are intertwined through the amidinium-carboxylate salt bridges. The structures and hydrodynamic dimensions of the metallosupramolecular polymers were characterized by 1H NMR, diffusion-ordered NMR, dynamic light scattering, absorption, and CD measurements. The polymeric structure was also visualized by atomic force microscopy.

  1. Long-term corrosion protection of bridge elements reinforcing materials in concrete : final report.

    Science.gov (United States)

    2017-09-01

    Preventing or mitigating the corrosion of reinforcing steel in bridge decks is a major challenge for state transportation agencies. With agency budgets stretched thinner every year, they must implement strategies to extend the service lives of bridge...

  2. Development and performance evaluation of fiber reinforced polymer bridge : [technical summary].

    Science.gov (United States)

    2014-03-01

    Conventionally, highway bridge decks in the US are predominantly made of steel-reinforced concrete. However, repair and : maintenance costs of these bridges incurred at the federal and state levels are overwhelming. As a result, for many years, there...

  3. The effect of span length and girder type on bridge costs

    Directory of Open Access Journals (Sweden)

    Batikha Mustafa

    2017-01-01

    Full Text Available Bridges have an important role in impacting the civilization, growth and economy of cities from ancient time until these days due to their function in reducing transportation cost and time. Therefore, development of bridges has been a knowledge domain in civil engineering studies in terms of their types and construction materials to confirm a reliable, safe, economic design and construction. Girder-bridge of concrete deck and I-beam girder has been used widely for short and medium span bridges because of ease and low-cost of fabrication. However, many theoretical and practical investigations are still undertaken regarding the type of beam girder; i.e steel composite or prestressed concrete. This paper evaluates the effect of bridge span and the type of girder on the capital cost and life cycle costs of bridges. Three types of girders were investigated in this research: steel composite, pre-tensioned pre-stressed concrete and post-tensioned pre-stressed concrete. The structural design was analyzed for 5 span lengths: 20, 25, 30, 35 and 40m. Then, the capital construction cost was accounted for 15 bridges according to each span and construction materials. Moreover, the maintenance required for 50 years of bridge life was evaluated and built up as whole life costs for each bridge. As a result of this study, the influence of both span length and type of girder on initial construction cost and maintenance whole life costs were assessed to support the decision makers and designers in the selection process for the optimum solution of girder bridges.

  4. Cable Supported Bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    Cable supported bridges in the form of suspension bridges and cable-stayed bridges are distinguished by their ability to overcome large spans.The book concentrates on the synthesis of cable supported bridges, covering both design and construction aspects. The analytical part covers simple methods...

  5. 77 FR 14276 - Regulated Navigation Area; Little Bay Bridge Construction, Little Bay, Portsmouth, NH

    Science.gov (United States)

    2012-03-09

    ... mail and would like to know that they reached the Facility, please enclose a stamped, self-addressed... construction work through July 31, 2013. Heavy-lift operations are sensitive to water movement, and wake from... minimize such unexpected or uncontrolled movement of water, the RNA will limit vessel speed and wake of all...

  6. The Two-Way Language Bridge: Co-Constructing Bilingual Language Learning Opportunities

    Science.gov (United States)

    Martin-Beltran, Melinda

    2010-01-01

    Using a sociocultural theoretical lens, this study examines the nature of student interactions in a dual immersion school to analyze affordances for bilingual language learning, language exchange, and co-construction of language expertise. This article focuses on data from audio- and video-recorded interactions of fifth-grade students engaged in…

  7. Bridging the Gap: New Constructs for Organizations and Appropriate Methodologies. ASHE 1984 Annual Meeting Paper.

    Science.gov (United States)

    Lincoln, Yvonna S.

    Conference papers calling for newer constructs in organizational theory to explicate problems in understanding educational organizations were content analyzed to explore paradigmatic assumptions and to demonstrate a fit between assumptions. Papers supporting the use of qualitative methodologies were also analyzed. The papers were from the 1983…

  8. Structural evaluation of the John A. Roebling Suspension Bridge : element level analysis.

    Science.gov (United States)

    2008-07-01

    The primary objective of the structural evaluation of the John A. Roebling Bridge is to determine the maximum allowable gross vehicle weight (GVW) that can be carried by the bridge deck structural elements such as the open steel grid deck, channels, ...

  9. History of cable-stayed bridges

    DEFF Research Database (Denmark)

    Gimsing, Niels Jørgen

    1999-01-01

    The principle of supporting a bridge deck by inclined tension members leading to towers on either side of the span has been known for centuries. However, the real development of cable-stayed bridges did not begin before the 1950s. Since then the free span has been increased from 183 m...

  10. INFLUENCE OF MOVING LOADS ON CURVED BRIDGES

    OpenAIRE

    Thamer A. Z*, Jabbbar S. A

    2016-01-01

    The behavior of a curved slab bridge decks with uniform thickness under moving load is investigated in this study. Three radii of curvature "R" are used (25, 50 and 75m) along with the straight bridge, R = ∞. The decks are simply supported or clamped along the radial edges and free at the circular edges. The AASHTO[1] standard axle load of the truck H20-44 is used and assumed to move in three track positions on the bridge. The finite element method is employed for the analysis and the ANSYS 5...

  11. Effective click construction of bridged- and spiro-multicyclic polymer topologies with tailored cyclic prepolymers (kyklo-telechelics).

    Science.gov (United States)

    Sugai, Naoto; Heguri, Hiroyuki; Ohta, Kengo; Meng, Qingyuan; Yamamoto, Takuya; Tezuka, Yasuyuki

    2010-10-27

    An alkyne-azide addition, i.e., click, reaction in conjunction with an electrostatic self-assembly and covalent fixation (ESA-CF) process has been demonstrated to effectively construct a variety of unprecedented multicyclic polymer topologies. A series of single cyclic poly(tetrahydrofuran), poly(THF), precursors having an alkyne group (Ia), an azide group (Ib), two alkyne groups at the opposite positions (Ic), and an alkyne group and an azide group at the opposite positions (Id) have been prepared by the ESA-CF process. Moreover, a bicyclic 8-shaped precursor having two alkyne groups at the opposite positions (Ie) was synthesized. The subsequent click reaction of Ia with linear (IIa) and three-armed star (IIb) telechelic precursors having azide groups has been performed to construct bridged-type two-way (IIIa) and three-way (IIIb) paddle-shaped polymer topologies, respectively. Likewise, spiro-type tandem tricyclic (IVa) and tetracyclic (IVb) topologies resulted from Ib/Ic and Ib/Ie, respectively. Furthermore, three types of multicyclic topologies that are composed of repeating ring (Va), alternating ring/linear (Vb), and alternating ring/star (Vc) units have been synthesized from Id, Ic/IIa, and Ic/IIb, respectively.

  12. Evaluation of Radiation Exposure during Construction and Operation of Concrete Bridge Reinforced with Very Low Level Radioactive Steel

    International Nuclear Information System (INIS)

    Panik, M.; Necas, V.

    2012-01-01

    A lot of nuclear power plants are approaching the end of their lifetime and they will be phased out. Decommissioning of these nuclear power plants involve complete dismantling of technologies and demolition of buildings. During this process it is produced plenty of waste material of different categories. Significant portion of decommissioning materials comprise radionuclides what is caused by contamination and activation processes mostly from the operational period of nuclear power plant. Attention in this paper is paid to waste steel from the decommissioning of nuclear power plants with the specific activity just slightly exceeding legislation limits for the unconditional release into the environment. From the traditional point of view this material should be treated, conditioned and disposed on the radioactive waste repository. Second possibility is to release this material conditionally and reuse it in chosen industrial application. Very low level radioactive steel scrap should be melted and melting products should be processed into products that can be applied in industry. First option requires considerable financial investment, human resources and repository capacity. Second option saves some financial funds and it enables to reuse and save potentially valuable material for the future. Paper comprises evaluation of external and internal exposure during construction and operation of concrete bridges that utilize very low level radioactive steel as part of their reinforcement. Two models of representative concrete bridges were created. External gamma exposure and exposure from inhalation and ingestion of radionuclides were calculated using suitable computational tools. VISIPLAN 3D ALARA planning tool was chosen for the calculation of external gamma exposure. Software GOLDSIM enables to calculate transport of radionuclides initially contained in conditionally released reinforcement steel through subsoil and sequential exposure of people caused by inhalation of

  13. On the typography of flight-deck documentation

    Science.gov (United States)

    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.

  14. Semiempirical Methodology for Estimating the Service Life of Concrete Deck Panels Strengthened with Fiber-Reinforced Polymer

    Directory of Open Access Journals (Sweden)

    Eon-Kyoung Kim

    2014-01-01

    Full Text Available Deterioration of concrete bridge decks affects their durability, safety, and function. It is therefore necessary to conduct structural rehabilitation of damaged concrete decks by strengthening them with fiber-reinforced polymer. Of the recent studies on the strengthened structures, most have focused on static behavior; only a few studies have investigated fatigue behavior. Accurate analysis of fatigue in concrete deck performance requires a more realistic simulated moving load. This study developed a theoretical live-load model to reflect the effect of moving vehicle loads, based on a statistical approach to the measurement of real traffic loads over various time periods in Korea. It assessed the fatigue life and strengthening effect of bridge decks strengthened with either carbon fiber sheets or grid carbon fiber polymer plastic using probabilistic and reliability analyses. It used extrapolations and simulations to derive maximum load effects for time periods ranging from 1 day to 75 years. Limited fatigue tests were conducted and probabilistic and reliability analyses were carried out on the strengthened concrete bridge deck specimens to predict the extended fatigue life. Analysis results indicated that strengthened concrete decks provide sufficient resistance against increasing truck loads during the service life of a bridge.

  15. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : final report appendices.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  16. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : appendices.

    Science.gov (United States)

    2012-01-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  17. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  18. Strength and durability of near-surface mounted CFRP bars for shear strengthening reinforced concrete bridge girders : final report.

    Science.gov (United States)

    2012-03-01

    During the interstate expansion of the 1950s, many conventionally reinforced concrete deck girder bridges were built throughout the country. These aging bridges commonly exhibit diagonal cracking and rate inadequately for shear, thus they are candida...

  19. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : final report.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of designing pre-tensioned prestressed concrete beam (PPCB) : bridges utilizing the continuity developed in the bridge deck as opposed to the current Iowa Department of Transportation (...

  20. Economic impact of multi-span, prestressed concrete girder bridges designed as simple span versus continuous span : tech transfer summary.

    Science.gov (United States)

    2016-10-01

    The objective of this study was to determine the economic impact of : designing pre-tensioned prestressed concrete beam (PPCB) bridges : utilizing the continuity developed in the bridge deck as opposed to the : current Iowa Department of Transportati...

  1. Experimental Investigation of a Self-Sensing Hybrid GFRP-Concrete Bridge Superstructure with Embedded FBG Sensors

    OpenAIRE

    Wang, Yanlei; Li, Yunyu; Ran, Jianghua; Cao, Mingmin

    2012-01-01

    A self-sensing hybrid GFRP-concrete bridge superstructure, which consists of two bridge decks and each bridge deck is comprised of four GFRP 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 four GFRP box sections at midspan section of one bridge deck along longitudinal direction, respectively. The proposed self-sensing hybrid bridge superstructure was tested in 4-point loading to...

  2. Estimating bridge stiffness using a forced-vibration technique for timber bridge health monitoring

    Science.gov (United States)

    James P. Wacker; Xiping Wang; Brian Brashaw; Robert J. Ross

    2006-01-01

    This paper describes an effort to refine a global dynamic testing technique for evaluating the overall stiffness of timber bridge superstructures. A forced vibration method was used to measure the frequency response of several simple-span, sawn timber beam (with plank deck) bridges located in St. Louis County, Minnesota. Static load deflections were also measured to...

  3. GARFEM input deck description

    Energy Technology Data Exchange (ETDEWEB)

    Zdunek, A.; Soederberg, M. (Aeronautical Research Inst. of Sweden, Bromma (Sweden))

    1989-01-01

    The input card deck for the finite element program GARFEM version 3.2 is described in this manual. The program includes, but is not limited to, capabilities to handle the following problems: * Linear bar and beam element structures, * Geometrically non-linear problems (bar and beam), both static and transient dynamic analysis, * Transient response dynamics from a catalog of time varying external forcing function types or input function tables, * Eigenvalue solution (modes and frequencies), * Multi point constraints (MPC) for the modelling of mechanisms and e.g. rigid links. The MPC definition is used only in the geometrically linearized sense, * Beams with disjunct shear axis and neutral axis, * Beams with rigid offset. An interface exist that connects GARFEM with the program GAROS. GAROS is a program for aeroelastic analysis of rotating structures. Since this interface was developed GARFEM now serves as a preprocessor program in place of NASTRAN which was formerly used. Documentation of the methods applied in GARFEM exists but is so far limited to the capacities in existence before the GAROS interface was developed.

  4. Numerical Analysis of Heat Storage and Heat Conductivity in the Concrete Hollow Core Deck Element

    DEFF Research Database (Denmark)

    Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

    2011-01-01

    In order to minimize energy used for cooling and heating, one of the passive solutions is to efficiently utilize heat storage of a building construction. Presently, heat storage calculations in whole building simulation programs are based on 1D heat transfer models. This paper investigates to what...... extent these simplified models estimate the heat storage potential of precast hollow-core concrete decks correctly. This study investigates various approaches on how to model the heat transfer within the air void in the deck. Furthermore, it is analysed how different heat transfer models influence...... method in BSim for the concrete deck element with air voids. Finally, this paper presents a comparison of the calculated heat conductivity of the hollow-core concrete deck and the measured heat conductivity for the same deck by using hot box apparatus....

  5. 75 FR 4584 - Wire Decking From China

    Science.gov (United States)

    2010-01-28

    ... COMMISSION Wire Decking From China AGENCY: United States International Trade Commission. ACTION: Scheduling... retarded, by reason of subsidized and less-than-fair-value imports from China of wire decking, provided for..., producers, or exporters in China of wire decking, and that such ] products are being sold in the United...

  6. Effects of channel relocation and proposed bridge construction on floodflows of the Catawba River near Marion, North Carolina

    Science.gov (United States)

    Stamey, T.C.

    1989-01-01

    The relocation of a part (about one-half a mile) of the Catawba River near Marion, North Carolina, and the proposed addition of a main bridge and an overflow bridge of U.S. Highway 221 have created the need for a current evaluation of the effects of these physical changes on floodflow in the river. The 100-year flood discharge, elevation-discharge relations, flood profiles, floodway, and flooding effects were determined for 1988 and for proposed bridge conditions. Analysis of data indicates that for the 100-year flood, the maximum amount of backwater effect from the proposed bridges would be 1.2 feet, and backwater would extend upstream about 6,800 feet. The 100-year flood elevation in the relocated channel reach will be about 6 feet lower than elevations determined in a 1983 U.S. Soil Conservation Service flood study.

  7. Evaluation of aerodynamic stability and a trial study of construction-accuracy control by daytime measurement of Meiko West Bridge; Meiko Nishi Ohashi no taifusei kento to chukan keisoku kekka wo mochiita kasetsu seido kanri no shiko

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, C.; Shimodoi, H.; Isoe, A.; Sakai, Y.; Ochiai, M.; Watabe, T.; Ebihara, R. [Kawasaki Heavy Industries, Ltd., Kobe (Japan)

    1998-12-20

    The new Meiko West Bridge was constructed very closely to the phase I line bridge which have been already in a service from 1985, and the distance of this world unique parallel cable-stayed bridges is 50m. The length, span and pylon height of these bridges are identical. By conducting wind tunnel experiments considering the aerodynamic interference of the close parallel bridges, the aerodynamic stability of the bridge had been confirmed during construction as well as complete state. After the construction was completed, the important wind characteristics of the parallel cable-stayed bridges were obtained from the site observation. Regarding cable vibrations, a common problem with cable-stayed bridges, a suitable vibration suppression method was applied based on the site observation. In general, the construction-accuracy control is performed by doing measurement at night However, to study the possibility of the accuracy-control by daytime measurement the measurement was conducted not only at night but also in the daytime. (author)

  8. Dynamic Heat Storage and Cooling Capacity of a Concrete Deck with PCM and Thermally Activated Building System

    DEFF Research Database (Denmark)

    Pomianowski, Michal Zbigniew; Heiselberg, Per; Jensen, Rasmus Lund

    2012-01-01

    with and without microencapsulated PCM are presented. The new concrete deck with microencapsulated PCM is the standard deck on which an additional layer of the PCM concrete was added and, at the same time, the latent heat storage was introduced to the construction. The challenge of numerically simulating...

  9. Construction and Operation of Railway Bridges and Ferries in the Lower Volga Streamflow (End of 19th – First Half of 20th Century

    Directory of Open Access Journals (Sweden)

    OPALEV M.N.

    2014-06-01

    Full Text Available The article deals with the history of operation of Russia’s first railway ferry and the process of bridge construction across the lower Volga streamflows at Ryazan-Ural (now Volga railway line in Saratov, Stalingrad (Volgograd and Astrakhan. River railway ferries “Saratovskaya pereprava” and “Saratovsky ledokol” were built in 1894 in England and water crafts “Vtoraya pereprava” (1909 and “Stalin” (1926 were floated out in Volga in Nizhny Novgorod, from the Sormov plant. As a rule, the organization of transportations by means of steam locomotives and waggons through Volga during the first half of the 20th century preceded the construction of capital metal railway bridges, such as Astrakhan (1909 and Saratov (1935, and also a combined railway-automobile bridge through the Volga (Stalingrad Hydro-Electric Power Station (1961. The article is devoted not only to the technical features of ferries, bridges, but their efficient use in peace time and war time. So, the carrying capacity of the Saratov railway ferry increased in more than three times from 1907 to 1916. The Ryazan-Ural railway ferries were actively used by new Bolshevist regime. After the railroad construction on the left bank of Volga in autumn and winter of 1941, railway ferries “Stalin” and “Saratovskaya pereprava” were used for the carriage of military trains and population evacuation from the western bank of Volga. The author describes one of the most heroic and tragic facts in the history of Stalingrad battle using the example of the special operation railway ferry flooding and its consequent reconstruction.

  10. Experimental Validation of a Numerical Model for Three-Dimensional High-Speed Railway Bridge Analysis by Comparison with a Small-Scale Model

    DEFF Research Database (Denmark)

    Sneideris, J.; Bucinskas, Paulius; Agapii, L.

    2015-01-01

    The aim of this paper is to perform dynamic analysis of a multi-span railway bridge interacting with the underlying soil. A small-scale model of a bridge structure is constructed for experimental testing and the results are compared with a computational model. The computational model in this paper...... is based on finite-element analysis for the bridge structure and a semi-analytical solution for the subsoil. The bridge deck and columns are modelled using three-dimensional beam elements. The foundations are implemented as rigid footings placed on the ground surface. The vehicle is modelled as a two...... a passing train. Mattress foam is used to substitute for the subsoil. The model is equipped with a number of accelerometers, strategically placed in certain positions to analyse the dynamic structural response. Finally, the results obtained from experimental tests are used to calibrate and validate...

  11. Field evaluation of corrosion inhibitors for concrete : interim report 2, evaluation of installation and initial condition of bridge repairs done with corrosion-inhibiting admixtures and topical treatments.

    Science.gov (United States)

    1999-06-01

    Four bridge decks were overlayed and patched and one bridge pier was patched using concrete with and without corrosion inhibiting admixtures. Some concrete surfaces received topically applied corrosion-inhibiting treatments prior to placement of the ...

  12. Constitutive and numerical modeling of soil and soil-pile interaction for 3D applications and Kealakaha stream bridge case study.

    Science.gov (United States)

    2011-12-01

    This study is concerned with developing new modeling tools for predicting the response of the new Kealakaha : Stream Bridge to static and dynamic loads, including seismic shaking. The bridge will span 220 meters, with the : deck structure being curve...

  13. Parametric Study on Dynamic Response of Fiber Reinforced Polymer Composite Bridges

    Directory of Open Access Journals (Sweden)

    Woraphot Prachasaree

    2015-01-01

    Full Text Available Because of high strength and stiffness to low self-weight ratio and ease of field installation, fiber reinforced polymer (FRP composite materials are gaining popularity as the materials of choice to replace deteriorated concrete bridge decks. FRP bridge deck systems with lower damping compared to conventional bridge decks can lead to higher amplitudes of vibration causing dynamically active bridge deck leading serviceability problems. The FRP bridge models with different bridge configurations and loading patterns were simulated using finite element method. The dynamic response results under varying FRP deck system parameters were discussed and compared with standard specifications of bridge deck designs under dynamic loads. In addition, the dynamic load allowance equation as a function of natural frequency, span length, and vehicle speed was proposed in this study. The proposed dynamic load allowance related to the first flexural frequency was presented herein. The upper and lower bounds’ limits were established to provide design guidance in selecting suitable dynamic load allowance for FRP bridge systems.

  14. Statistical Analysis of Stress Signals from Bridge Monitoring by FBG System.

    Science.gov (United States)

    Ye, Xiao-Wei; Su, You-Hua; Xi, Pei-Sen

    2018-02-07

    In this paper, a fiber Bragg grating (FBG)-based stress monitoring system instrumented on an orthotropic steel deck arch bridge is demonstrated. The FBG sensors are installed at two types of critical fatigue-prone welded joints to measure the strain and temperature signals. A total of 64 FBG sensors are deployed around the rib-to-deck and rib-to-diagram areas at the mid-span and quarter-span of the investigated orthotropic steel bridge. The local stress behaviors caused by the highway loading and temperature effect during the construction and operation periods are presented with the aid of a wavelet multi-resolution analysis approach. In addition, the multi-modal characteristic of the rainflow counted stress spectrum is modeled by the method of finite mixture distribution together with a genetic algorithm (GA)-based parameter estimation approach. The optimal probability distribution of the stress spectrum is determined by use of Bayesian information criterion (BIC). Furthermore, the hot spot stress of the welded joint is calculated by an extrapolation method recommended in the specification of International Institute of Welding (IIW). The stochastic characteristic of stress concentration factor (SCF) of the concerned welded joint is addressed. The proposed FBG-based stress monitoring system and probabilistic stress evaluation methods can provide an effective tool for structural monitoring and condition assessment of orthotropic steel bridges.

  15. Statistical Analysis of Stress Signals from Bridge Monitoring by FBG System

    Directory of Open Access Journals (Sweden)

    Xiao-Wei Ye

    2018-02-01

    Full Text Available In this paper, a fiber Bragg grating (FBG-based stress monitoring system instrumented on an orthotropic steel deck arch bridge is demonstrated. The FBG sensors are installed at two types of critical fatigue-prone welded joints to measure the strain and temperature signals. A total of 64 FBG sensors are deployed around the rib-to-deck and rib-to-diagram areas at the mid-span and quarter-span of the investigated orthotropic steel bridge. The local stress behaviors caused by the highway loading and temperature effect during the construction and operation periods are presented with the aid of a wavelet multi-resolution analysis approach. In addition, the multi-modal characteristic of the rainflow counted stress spectrum is modeled by the method of finite mixture distribution together with a genetic algorithm (GA-based parameter estimation approach. The optimal probability distribution of the stress spectrum is determined by use of Bayesian information criterion (BIC. Furthermore, the hot spot stress of the welded joint is calculated by an extrapolation method recommended in the specification of International Institute of Welding (IIW. The stochastic characteristic of stress concentration factor (SCF of the concerned welded joint is addressed. The proposed FBG-based stress monitoring system and probabilistic stress evaluation methods can provide an effective tool for structural monitoring and condition assessment of orthotropic steel bridges.

  16. reliability assessment of stringers spacings in bridges as function

    African Journals Online (AJOL)

    user

    rapid deterioration of both steel and concrete bridges and components. Also, when a larger structural timber is exposed to fire, there is some delay in failure as it chars and eventually flames. Treated timber bridge decks can be built in days and not weeks, because materials are low energy certified, reusable and renewable ...

  17. Pennsylvania hardwood timber bridges : field performance after 10 years

    Science.gov (United States)

    James P. Wacker; Carlito Calil

    2004-01-01

    Several hardwood demonstration timber bridges were built by the Pennsylvania Department of Transportation in the early nineteen nineties. These bridge superstructures are of the recently developed stress-laminated deck design-type using Red Oak lumber laminations that were pressure-treated with creosote preservatives. This paper will describe the data acquisition...

  18. Forensic collapse investigation of a concrete bridge with timber piers.

    Science.gov (United States)

    2009-04-01

    This report outlines the forensic investigation of the collapse of Bridge No. SN 019-5010 in DeKalb County, : Illinois on August 19, 2008. The bridge consisted of three 42 feet precast prestressed concrete deck beams : simply-supported by concrete pi...

  19. 78 FR 59231 - Regulated Navigation Area-Tappan Zee Bridge Construction Project, Hudson River; South Nyack and...

    Science.gov (United States)

    2013-09-26

    ... enforce speed and wake restrictions and prohibit all vessel traffic through the RNA during bridge... and would like to know that they reached the Facility, please enclose a stamped, self-addressed... speed and wake restrictions and to prohibit vessel traffic on this portion of the river for limited...

  20. Influence of Different Techniques of Laboratory Construction on the Fracture Resistance of Fiber-Reinforced Composite (FRC) Bridges.

    Science.gov (United States)

    Ellakwa, Ayman E; Shortall, Adrian C; Marquis, Peter M

    2004-11-15

    The aim of the current investigation is to evaluate optimal pontic and retainer fiber positions for Polyethylene fiber-reinforced composite (FRC) restorations. In series I notch disc specimens were used to mimic loading cuspal regions of pontics. Four groups (n=15/group; codes A to D) were prepared from Artglass composite. Groups A to C were reinforced with polyethylene fibers, and group D was an unreinforced control. Fibers were positioned either around (A), beneath the notch (B), or at the disc base (C). Specimens were stored in distilled water at 37 degrees C for 24 h before testing to failure (CHS=1mm/min) in a universal testing machine. Mean torque to failure values ranked [P C = D. In series II five groups of three unit bridges (n =5/group; codes A to E) were prepared from Artglass dental composite without (group A) or with (groups B to E) different Connect fiber reinforcement locations/techniques. Bridges were cemented using 2 bond resin cement to a standardized substructure. After storage, as per series I, bridges were loaded mid-pontic region to failure. One-way ANOVA showed no significant (P=0.08) difference between test groups. The research hypothesis was that notched disc and 3 unit bridge test techniques would discriminate equally between fiber-reinforced specimens and an unreinforced composite control was rejected.

  1. Total heat loss coefficient of flat roof constructions with external insulation in tapered layers including the effects of thermal bridges

    DEFF Research Database (Denmark)

    Rose, Jørgen; Svendsen, Svend

    2005-01-01

    be quite tedious, and therefore a method to generate and optimize solutions has been developed and implemented in a program that also takes into account the effects of different types of thermal bridges, i.e. roof windows, insulation fasteners, roof/wall joints etc. This paper describes a new method...

  2. Design of bridges against large tectonic deformation

    Science.gov (United States)

    Anastasopoulos, I.; Gazetas, G.; Drosos, V.; Georgarakos, T.; Kourkoulis, R.

    2008-12-01

    The engineering community has devoted much effort to understanding the response of soil-structure systems to seismic ground motions, but little attention to the effects of an outcropping fault offset. The 1999 earthquakes of Turkey and Taiwan, offering a variety of case histories of structural damage due to faulting, have (re)fueled the interest on the subject. This paper presents a methodology for design of bridges against tectonic deformation. The problem is decoupled in two analysis steps: the first (at the local level) deals with the response of a single pier and its foundation to fault rupture propagating through the soil, and the superstructure is modeled in a simplified manner; and the second (at the global level) investigates detailed models of the superstructure subjected to the support (differential) displacements of Step 1. A parametric study investigates typical models of viaduct and overpass bridges, founded on piles or caissons. Fixed-head piled foundations are shown to be rather vulnerable to faulting-induced deformation. End-bearing piles in particular are unable to survive bedrock offsets exceeding 10 cm. Floating piles perform better, and if combined with hinged pile-to-cap connections, they could survive much larger offsets. Soil resilience is beneficial in reducing pile distress. Caisson foundations are almost invariably successful. Statically-indeterminate superstructures are quite vulnerable, while statically-determinate are insensitive (allowing differential displacements and rotations without suffering any distress). For large-span cantilever-construction bridges, where a statically determinate system is hardly an option, inserting resilient seismic isolation bearings is advantageous as long as ample seating can prevent the deck from falling off the supports. An actual application of the developed method is presented for a major bridge, demonstrating the feasibility of design against tectonic deformation.

  3. Temperature effects on the bridge structure during the all-day monitoring

    Directory of Open Access Journals (Sweden)

    Ondřej Michal

    2015-06-01

    Full Text Available In current time the large amount of pre-stressed bridge structures is used. Their horizontal and vertical displacements are well predicted, but for verification of theoretical results is necessary to measure real displacements of these structures depending on external conditions. Given by the complexity of the design and by the inhomogeneity of external influences (especially temperature of the atmosphere, insolation, wind speed, etc. cannot yet be reliably determined the changes of the construction caused by the immediate state of the environment and to distinguish them from irreversible (permanent deformation of the structure.In this paper the deflection line of the bridge of general Chábera over river Labe during the all-day monitoring will be analyzed. There is dense coverage of stabilized points enabling accurate approximation of the displacement of the bridge structure. The paper is focused especially on temperature effects on the bridge structure. The temperature changes cause the deformation of the construction not immediately, but with the time shift between change of temperature and structure deformation. Although the points are stabilized on both sides of the bridge deck, for the analysis of results were used only the points on the left side of the main span, where the biggest vertical displacements was detected. For testing of dependence of the time shift between the structure deformations and the structure temperature the Pearson coefficient of correlation was used.

  4. Fatigue of bridges with a horizontal rotation axle under random wind load

    NARCIS (Netherlands)

    Maljaars, J.; Steenbergen, R.D.J.M.

    2012-01-01

    The operating mechanisms of movable bridges are subjected to various types of fluctuating loads which may induce fatigue damage. Wind load acting on the bridge deck - when the bridge is open - is one of the important load types. A wind load model is proposed that can be used in the fatigue design

  5. Computer Models Identify Methods to Reduce Bridge Cracks During Production Processes : Brief

    Science.gov (United States)

    2012-06-01

    While most motorists see only the bridge deck, strong bridge girders are the basis for a stable system to support the traffic-handling surface. Concrete bridge girders often have two major components: the web, which is an I-shaped cross section and v...

  6. Fatigue Reliability Assessment for Orthotropic Steel Decks Based on Long-Term Strain Monitoring.

    Science.gov (United States)

    Deng, Yang; Li, Aiqun; Feng, Dongming

    2018-01-10

    A time-dependent fatigue reliability assessment approach is proposed for welded details of orthotropic steel decks (OSDs) using long-term strain monitoring data. The fatigue reliability limit function of the welded details is established based on the Eurocode specifications. Depending on the distribution characteristics of the measured daily equivalent stress range, either the lognormal distribution or Gaussian mixture model (GMM) is selected to quantify its uncertainty. Subsequently, the fatigue reliability can be calculated using either an explicit formula or the Monte Carlo method. This proposed approach is applied for the fatigue reliability evaluation of two rib-to-deck and two rib-to-rib welded fatigue details of an in-service suspension bridge. The results show that the reliability indices decrease significantly with bridge's service life. Except for a rib-to-deck detail, all other three welded details cannot meet the target fatigue reliability during this bridge's 100-year service life. The proposed approach can help bridge owners and operators make informed decisions regarding maintenance and repair of potential fatigue cracks.

  7. Seismic Performance of Multi-Span RC Railway Bridges

    DEFF Research Database (Denmark)

    Georgakis, Christos; Barrau, Xavier

    2008-01-01

    Presently, there is no clear method for determining the optimal railway bridge design for a particular ground type and expected seismic intensity. Four main types of RC bridge dominate the current multi-span railway bridge design trends – the Simply Supported Beam, Continuous Box-Girder (CBG), CBG...... with Lead Rubber Bearing (LRB) supports and the laterally fixed continuous deck (CRB) with LRBs. In this paper, the seismic performance of these four types is examined for varying ground types and seismic intensities. For the purposes of comparison, all of the bridges have five spans with identical span...... lengths and topography. Initially, typical bridge deck, pier and bearing configurations are chosen and analyzed through a series of nonlinear time-history analyses using synthetic accelerograms, in which plastic hinge formation is permitted. Next, an optimization of the bridge configurations is undertaken...

  8. Myocardial Bridge

    Science.gov (United States)

    ... Center > Myocardial Bridge Menu Topics Topics FAQs Myocardial Bridge Article Info En español Your heart is made ... surface of the heart. What is a myocardial bridge? A myocardial bridge is a band of heart ...

  9. Fatigue Performance Assessment of Composite Arch Bridge Suspenders Based on Actual Vehicle Loads

    Directory of Open Access Journals (Sweden)

    Bin Chen

    2015-01-01

    Full Text Available In the through arch bridges, the suspenders are the key components connecting the arch rib and the bridge deck in the middle, and their safety is an increasing focus in the field of bridge engineering. In this study, various vehicle traffic flow parameters are investigated based on the actual vehicle data acquired from the long-term structural health monitoring system of a composite arch bridge. The representative vehicle types and the probability density functions of several parameters are determined, including the gross vehicle weight, axle weight, time headway, and speed. A finite element model of the bridge structure is constructed to determine the influence line of the cable force for various suspenders. A simulated vehicle flow, generated using the Monte Carlo method, is applied on the influence lines of the target suspender to determine the stress process, and then the stress amplitude spectrum is obtained based on the statistical analysis of the stress process using the rainflow counting method. The fatigue performance levels of various suspenders are analyzed according to the Palmgren-Miner linear cumulative damage theory, which helps to manage the safety of the suspenders.

  10. Covered Bridge Security Manual

    Science.gov (United States)

    Brett Phares; Terry Wipf; Ryan Sievers; Travis Hosteng

    2013-01-01

    The design, construction, and use of covered timber bridges is all but a lost art in these days of pre-stressed concrete, high-performance steel, and the significant growth both in the volume and size of vehicles. Furthermore, many of the existing covered timber bridges are preserved only because of their status on the National Registry of Historic Places or the...

  11. Stochastic Assessment of Nigerian Wood for Bridge Decks | Owoeye ...

    African Journals Online (AJOL)

    Nigerian Journal of Technology. Journal Home · ABOUT THIS JOURNAL · Advanced Search · Current Issue · Archives · Journal Home > Vol 34, No 2 (2015) >. Log in or Register to get access to full text downloads.

  12. Damage identification of RC bridge decks under fatigue loading

    Directory of Open Access Journals (Sweden)

    Zanuy, C.

    2014-12-01

    Full Text Available The complex nature of structural phenomena still requires the comparison between numerical models and the real structural performance. Accordingly, many civil structures are monitored to detect structural damage and provide updated data for numerical models. Monitoring usually relies on the change of dynamic properties (experimental modal analysis. Regarding concrete structures, existing works have typically focused on the progressive decrease of natural frequencies under gradually increasing loads. In this paper, high-cycle fatigue effects are analyzed. An experimental campaign on specimens reproducing the top slab of concrete girders has been carried out, including fatigue tests and a reference static test. Impact-excitation tests were done at different stages to extract dynamic properties. Output-only models (only based on the structural response to an external excitation that is not measured were used as identification techniques. The evolution of dynamic properties was correlated with damage development, with emphasis on the fatigue process stages: crack formation, cyclic reduction of tension-stiffening and brittle fracture of the reinforcement.La naturaleza compleja de muchos fenómenos estructurales requiere que los modelos numéricos necesiten ser verificados con el comportamiento estructural real. Por ello, muchas estructuras son monitorizadas, tanto para detectar posibles daños estructurales como para proporcionar datos a incluir en los modelos. A menudo, la monitorización se basa en el cambio de las propiedades dinámicas mediante técnicas de análisis modal experimental. Con respecto al hormigón estructural, la mayoría de los trabajos existentes se ha centrado en el cambio de las frecuencias propias con cargas monótonamente crecientes. En este artículo se analizan los efectos de la fatiga. Se ha llevado a cabo una campaña experimental sobre piezas que reproducen la losa superior de tableros de puentes, realizándose ensayos de fatiga y uno estático de referencia. Las propiedades dinámicas se han ido extrayendo mediante técnicas de output-only a partir de ensayos de excitación mediante impacto. El cambio de las propiedades dinámicas se ha correlacionado con las etapas del proceso de fatiga: formación de fisuras, reducción de tension-stiffening y rotura frágil de la armadura.

  13. a finite element model for the analysis of bridge decks

    African Journals Online (AJOL)

    Dr Obe

    ε(x, y) State of stress at a point σ(x, y). State of stress at a point. [D]. Elasticity matrix θx, θy. Rotations ... the partial differential equation for the deflection w of an orthotropic plate: ( ) (1) where 2H is the torsional ... θx, θy) and a cubic displacement model, (Fig. 2). Studies by Gallagher [4] showed that this element is efficient and ...

  14. Is deck C an advantageous deck in the Iowa Gambling Task?

    Directory of Open Access Journals (Sweden)

    Lin Ching-Hung

    2007-08-01

    Full Text Available Abstract Background Dunn et al. performed a critical review identifying some problems in the Somatic Marker Hypothesis (SMH. Most of the arguments presented by Dunn focused on the insufficiencies for replication of skin conductance responses and somatic brain loops, but the study did not carefully reassess the core-task of SMH. In a related study, Lin and Chiu et al. identified a serious problem, namely the "prominent deck B phenomenon" in the original IGT. Building on this observation, Lin and Chiu also posited that deck C rather than deck A was preferred by normal decision makers due to good gain-loss frequency rather than good final-outcome. To verify this hypothesis, a modified IGT was designed that possessed high contrast of gain-loss value in each trial, with the aim of achieving a balance between decks A and C in terms of gain-loss frequency. Based on the basic assumption of IGT, participants should prefer deck C to deck A based on consideration of final-outcome. In contrast, based on the prediction of gain-loss frequency, participants should have roughly equal preferences for decks A and C. Methods This investigation recruited 48 college students (24 males and 24 females as participants. Two-stage IGT with high-contrast gain-loss value was launched to examine the deck C argument. Each participant completed the modified IGT twice and immediately afterwards was administered a questionnaire to assess their consciousness and final preferences following the game. Results The experimental results supported the predictions regarding gain-loss frequency participants choose the deck C with nearly identical frequency to deck A, despite deck C having a better final outcome than deck A. The "sunken deck C" phenomenon is clearly identified in this version of IGT which achieves a balance in gain-loss frequency. Moreover, the "sunken deck C" phenomenon not only appears during the first stage, but also during the second stage of IGT. In addition

  15. Drilling, construction, caliper-log, and specific-conductance data for well 3-3406-12, Twin Bridge Road deep monitor well, Oahu, Hawaii

    Science.gov (United States)

    Presley, T.K.; Oki, D.S.

    1996-01-01

    The Twin Bridge Road deep monitor well (State well number 3-3406-12) was drilled about 2,000 feet northeast of Weed Circle in the town of Haleiwa. The well is on agricultural land. The well penetrates through the freshwater lens and into the freshwater-saltwater transition zone of the Waialua ground-water area to an elevation of -596 feet below mean sea level. Well-construction data, logs of drilling notes, geologic descriptions for the samples, caliper-log, and specific-conductance data are presented for the well. The well is one of 12 exploratory wells drilled in the north- central Oahu area between July 1993 and May 1994 in cooperation with the Honolulu Board of Water Supply.

  16. The induction of dentin bridge-like structures by constructs of subcultured dental pulp-derived cells and porous HA/TCP in porcine teeth.

    Science.gov (United States)

    Ando, Yusuke; Honda, Masaki J; Ohshima, Hayato; Tonomura, Akiko; Ohara, Takayuki; Itaya, Toshimitsu; Kagami, Hideaki; Ueda, Minoru

    2009-02-01

    The purpose of this study was to investigate dentin-bridge formation in teeth following the transplantation of dental pulp-derived cells seeded on hydroxyapatite/tricalcium phosphate (HA/TCP) scaffolds. The dental pulp tissues were removed from the extracted first molar teeth of miniature pigs and single cell populations were subcultured. Second-passage cells that had alkaline phosphatase activity were combined with scaffolds. Cell-scaffold constructs were placed in contact with the exposed pulp tissue. The dimensions of the exposed pulp site were approximately 1-2.5 mm in diameter and 2-3 mm in depth from the tooth surface. After placing the constructs, the tooth was restored with composite resin. Six weeks after transplantation, hard tissue formation was observed on the pulp tissue in histology. Dentinal tubule-like structures were observed in most of the hard tissue generated, and columnar cells, which showed positive immunoreactions with dentin sialoprotein (DSP) and heat shock protein (HSP)-25, were aligned beneath the hard tissues. When only scaffolds were placed on the pulp tissues, particles of hard tissue were formed, however dentinal tubule-like structures and odontoblasts were not observed despite the formation of hard tissue. In conclusion, the implantation of dental pulp constructs into pulp exposed stimulates the formation of calcified dentin-like structures.

  17. Influences of high-flow events on a stream channel altered by construction of a highway bridge: A case study

    Science.gov (United States)

    Hedrick, Lara B.; Welsh, Stuart A.; Anderson, James T.

    2009-01-01

    Impacts of highway construction on streams in the central Appalachians are a growing concern as new roads are created to promote tourism and economic development in the area. Alterations to the streambed of a first-order stream, Sauerkraut Run, Hardy County, WV, during construction of a highway overpass included placement and removal of a temporary culvert, straightening and regrading of a section of stream channel, and armourment of a bank with a reinforced gravel berm. We surveyed longitudinal profiles and cross sections in a reference reach and the altered reach of Sauerkraut Run from 2003 through 2007 to measure physical changes in the streambed. During the four-year period, three high-flow events changed the streambed downstream of construction including channel widening and aggradation and then degradation of the streambed. Upstream of construction, at a reinforced gravel berm, bank erosion was documented. The reference section remained relatively unchanged. Knowledge gained by documenting channel changes in response to natural and anthropogenic variables can be useful for managers and engineers involved in highway construction projects.

  18. Delamination Detection of Reinforced Concrete Decks Using Modal Identification

    Directory of Open Access Journals (Sweden)

    Shutao Xing

    2012-01-01

    Full Text Available This study addressed delamination detection of concrete slabs by analyzing global dynamic responses of structures. Both numerical and experimental studies are presented. In the numerical examples, delaminations with different sizes and locations were introduced into a concrete slab; the effects of presence, sizes, and locations of delaminations on the modal frequencies and mode shapes of the concrete slab under various support conditions were studied. In the experimental study, four concrete deck specimens with different delamination sizes were constructed, and experimental tests were conducted. Traditional peak-picking, frequency domain decomposition, and stochastic subspace identification methods were applied to the modal identification from dynamic response measurements. The modal parameters identified by these three methods correlated well. The changes in modal frequencies, damping ratios, and mode shapes that were extracted from the dynamic measurements were investigated and correlated to the actual delaminations and can indicate presence and severity of delamination. Finite element (FE models of reinforced concrete decks with different delamination sizes and locations were established. The modal parameters computed from the FE models were compared to those obtained from the laboratory specimens, and the FE models were validated. The delamination detection approach was proved to be effective for concrete decks on beams.

  19. Procedure to the collapse of the Tacoma Narrows Bridge

    Science.gov (United States)

    Kim, Woojin; Choi, Heacheon

    2017-11-01

    The Tacoma Narrows Bridge (TNB) was collapsed in 1940 at the wind speed (U) of 18m/s corresponding to Re = 3000000 based on the height (H=2.4m) of the deck. The deck was lifted by two cables with 110 hangers and each cable was suspended by two towers. The deck experienced a vertical vibration with the spanwise wavelengths (l) of 1/4 and 1/4.5 of the deck length (L) and the non-dimensional frequency of St = fH/U = 0.08, followed by a torsional vibration with l = L and St = 0.027. We investigate the procedure before the collapse of the TNB using numerical simulation with fluid-structure interaction. We consider Re = 300 and 1000 because the non-dimensional frequency of vortex shedding is not much changed by the change in the Reynolds number due to a fixed separation point at the leading edge of the deck. A nonlinear model for a suspension bridge (Arioli & Gazzola, 2017) is used for the motion of the TNB. Initially, two-dimensional vortex shedding is generated with a weak vibration of the deck. Then, the deck oscillates vertically with l = L/4.5 and St = 0.09, together with three-dimensional vortical structures behind the deck. Finally, the deck oscillates torsionally with l = L and St = 0.033. These predicted vibrations of the TNB are in good agreements with those occurred in 1940. Supported by NRF-2016R1E1A1A02921549.

  20. Railroad Bridges

    Data.gov (United States)

    Department of Homeland Security — Bridges-Rail in the United States According to The National Bridge Inspection Standards published in the Code of Federal Regulations (23 CFR 650.3), a bridge isA...

  1. Deck41 Surficial Seafloor Sediment Description Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deck41 is a digital summary of surficial sediment composition for 36,401 seafloor samples worldwide. Data include collecting source, ship, cruise, sample id,...

  2. 33 CFR 155.790 - Deck lighting.

    Science.gov (United States)

    2010-07-01

    ... horizontal plane 3 feet above the deck the illumination must measure at least: (1) 5.0 foot candles at transfer connection points; and (2) 1.0 foot candle in transfer operations work areas. (c) Lighting must be...

  3. Flight Deck I-Glasses, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Flight Deck i-Glasses is a color, stereoscopic 3-D display mounted on consumer style eye glass frames that will enhance operator performance and multi-modal...

  4. The stories of two bridges in Ghana

    DEFF Research Database (Denmark)

    Andreasen, Jørgen

    2004-01-01

    Public participation in bridge building was promoted by un habitat in the village of Mankrong. The neighbouring village did not participate in the construction of their bridge. The first flooding washed the second bridge down while the "participative bridge" stood up....

  5. Is deck B a disadvantageous deck in the Iowa Gambling Task?

    Directory of Open Access Journals (Sweden)

    Chiu Yao-Chu

    2007-03-01

    Full Text Available Abstract Background The Iowa gambling task is a popular test for examining monetary decision behavior under uncertainty. According to Dunn et al. review article, the difficult-to-explain phenomenon of "prominent deck B" was revealed, namely that normal decision makers prefer bad final-outcome deck B to good final-outcome decks C or D. This phenomenon was demonstrated especially clearly by Wilder et al. and Toplak et al. The "prominent deck B" phenomenon is inconsistent with the basic assumption in the IGT; however, most IGT-related studies utilized the "summation" of bad decks A and B when presenting their data, thereby avoiding the problems associated with deck B. Methods To verify the "prominent deck B" phenomenon, this study launched a two-stage simple version IGT, namely, an AACC and BBDD version, which possesses a balanced gain-loss structure between advantageous and disadvantageous decks and facilitates monitoring of participant preferences after the first 100 trials. Results The experimental results suggested that the "prominent deck B" phenomenon exists in the IGT. Moreover, participants cannot suppress their preference for deck B under the uncertain condition, even during the second stage of the game. Although this result is incongruent with the basic assumption in IGT, an increasing number of studies are finding similar results. The results of the AACC and BBDD versions can be congruent with the decision literatures in terms of gain-loss frequency. Conclusion Based on the experimental findings, participants can apply the "gain-stay, loss-shift" strategy to overcome situations involving uncertainty. This investigation found that the largest loss in the IGT did not inspire decision makers to avoid choosing bad deck B.

  6. Precast Pearl-Chain concrete arch bridges

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

    2015-01-01

    A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post......-tensioning cables, the rise to span ratio, the height of the filling, and the height of the Super-Light Decks. We find that Pearl-Chain Bridges can be adjusted to resist specific moment loads by changing the normal force in the arch cross section by altering the above parameters. It is also found that the negative...

  7. Investigating extreme event loading on coastal bridges using wireless sensor technology

    Science.gov (United States)

    Gelineau, Douglas A.; Davis, Justin R.; Rice, Jennifer A.

    2017-04-01

    Coastal infrastructure, such as bridges, are susceptible to many forms of coastal hazards: particularly hurricane surge and wave loading. These two forms of loading can cause catastrophic damage to aging highway infrastructure. It is estimated that storm damage costs the United States about $50 Billion per year. In light of this, it is crucial that we understand the damaging forces placed on infrastructure during storm events so that we can develop safer and more resilient coastal structures. This paper presents the ongoing research to enable the efficient collection of extreme event loads acting on both the substructure and superstructure of low clearance, simple span, reinforced concrete bridges. Bridges of this type were commonly constructed during the 1950's and 60's and are particularly susceptible to deck unseating caused by hurricane surge and wave loading. The sensing technology used to capture this data must be ruggedized to survive in an extremely challenging environment, be designed to allow for redundancy in the event of sensors or other network components being lost in the storm, and be relatively low cost to allow for more bridges to be instrumented per storm event. The prototype system described in this paper includes wireless technology, rapid data transmission, and, for the sensors, self-contained power. While this specific application focuses on hurricane hazards, the framework can be extended to include other natural hazards.

  8. Bridges analysis, design, structural health monitoring, and rehabilitation

    CERN Document Server

    Bakht, Baidar

    2015-01-01

    This book offers a valuable guide for practicing bridge engineers and graduate students in structural engineering; its main purpose is to present the latest concepts in bridge engineering in fairly easy-to-follow terms. The book provides details of easy-to-use computer programs for: ·      Analysing slab-on-girder bridges for live load distribution. ·      Analysing slab and other solid bridge components for live load distribution. ·      Analysing and designing concrete deck slab overhangs of girder bridges under vehicular loads. ·      Determining the failure loads of concrete deck slabs of girder bridges under concentrated wheel loads. In addition, the book includes extensive chapters dealing with the design of wood bridges and soil-steel bridges. Further, a unique chapter on structural health monitoring (SHM) will help bridge engineers determine the actual load carrying capacities of bridges, as opposed to their perceived analytical capacities. The chapter addressing structures...

  9. Probabilistic and sensitivity analysis of Botlek Bridge structures

    Directory of Open Access Journals (Sweden)

    Králik Juraj

    2017-01-01

    Full Text Available This paper deals with the probabilistic and sensitivity analysis of the largest movable lift bridge of the world. The bridge system consists of six reinforced concrete pylons and two steel decks 4000 tons weight each connected through ropes with counterweights. The paper focuses the probabilistic and sensitivity analysis as the base of dynamic study in design process of the bridge. The results had a high importance for practical application and design of the bridge. The model and resistance uncertainties were taken into account in LHS simulation method.

  10. Field demonstration of new bridge approach slab designs and performance : [research project capsule].

    Science.gov (United States)

    2008-10-01

    A normal bridge approach slab in Louisiana is a reinforced concrete slab. It connects : the bridge deck to the adjacent paved roadway. Its intended functions are: : 1. To span the void that may develop below the slab due to soil erosion or : embankme...

  11. Wind-Tunnel Tests of a Bridge Model with Active Vibration Control

    DEFF Research Database (Denmark)

    Hansen, H. I.; Thoft-Christensen, Palle; Mendes, P. A.

    The application of active control systems to reduce wind vibrations in bridges is a new area of research. This paper presents the results that were obtained on a set of wind tunnel tests of a bridge model equipped with active movable flaps. Based on the monitored position and motion of the deck...

  12. Building a Straw Bridge

    Science.gov (United States)

    Teaching Science, 2015

    2015-01-01

    This project is for a team of students (groups of two or three are ideal) to design and construct a model of a single-span bridge, using plastic drinking straws as the building material. All steps of the design, construction, testing and critiquing stages should be recorded by students in a journal. Students may like to include labelled diagrams,…

  13. Recycled aggregate in road construction following the Spanish General Technical Specifications for Roads and Bridge Works (PG-3: a case study

    Directory of Open Access Journals (Sweden)

    Martín-Morales, M.

    2013-03-01

    Full Text Available This research characterizes four samples of recycled aggregate for their potential use in road construction projects in consonance with the Spanish General Technical Specifications for Roads and Bridge Works (PG-3. Although some fractions were of sufficient quality for the construction of embankments, backfills, and quarry-run fills, they were ultimately found to be unsuitable for the construction of underground drainage, granular structural layers, soil stabilization and concrete pavements. They were negatively evaluated because of their particle size distribution and sulfate content. Nevertheless, the quality of this recycled aggregate could be substantially improved by manually removing the gypsum before the crushing process at the plant or by selecting the material with greater care at the beginning of the process. Finally, we suggest that Construction and Demolition (C&D waste plant managers should modify the manufacturing process to obtain a suitable particle size distribution in accordance with PG-3 requirements and the projected use of the aggregate.

    En esta investigación se han caracterizado cuatro muestras de árido reciclado para su potencial uso en obras de carreteras en España siguiendo el Pliego de Prescripciones Técnicas Generales para Obras de Carreteras y Puentes (PG-3. Aunque algunas fracciones presentaron suficiente calidad para la construcción de terraplenes, rellenos localizados y rellenos todo en uno, resultaron inadecuadas para la construcción de drenes subterráneos, zahorras, suelos estabilizados y pavimentos de hormigón. Obtuvieron una evaluación negativa en cuanto a distribución granulométrica y contenido en sulfatos. No obstante, la calidad de este árido reciclado podría mejorar sustancialmente eliminando manualmente el yeso antes de la trituración en planta o seleccionando el material con un mayor cuidado al inicio del proceso. Finalmente, recomendamos que los empresarios de las plantas de residuos

  14. Long-term behavior of integral abutment bridges : [technical summary].

    Science.gov (United States)

    2011-01-01

    Integral abutment bridges, a type of jointless bridge, are the construction option of choice when designing highway bridges in many parts of the country. Rather than providing an expansion joint to separate the substructure from the superstructure to...

  15. Statistical variations in chloride diffusion in concrete bridges

    Czech Academy of Sciences Publication Activity Database

    Tikalsky, P.; Pustka, D.; Marek, Pavel

    2005-01-01

    Roč. 102, č. 3 (2005), s. 481-486 ISSN 0889-3241 Institutional research plan: CEZ:AV0Z20710524 Keywords : bridge deck * corrosion * durability Subject RIV: JM - Building Engineering Impact factor: 0.544, year: 2005

  16. reliability assessment of stringers spacings in bridges as function

    African Journals Online (AJOL)

    user

    dependent variable on other variables using Analysis of Variance (ANOVA) and multiple Regression line analysis. ... ≤0.05). Keywords: ANOVA, bridge decks, Flanagan polynomial, Nigerian timber, regression, reliability, stringer spacing. Nomenclature. 1 ... simple linear formulation for supporting stringers spacing when ...

  17. Stress Regression Analysis of Asphalt Concrete Deck Pavement Based on Orthogonal Experimental Design and Interlayer Contact

    Science.gov (United States)

    Wang, Xuntao; Feng, Jianhu; Wang, Hu; Hong, Shidi; Zheng, Supei

    2018-03-01

    A three-dimensional finite element box girder bridge and its asphalt concrete deck pavement were established by ANSYS software, and the interlayer bonding condition of asphalt concrete deck pavement was assumed to be contact bonding condition. Orthogonal experimental design is used to arrange the testing plans of material parameters, and an evaluation of the effect of different material parameters in the mechanical response of asphalt concrete surface layer was conducted by multiple linear regression model and using the results from the finite element analysis. Results indicated that stress regression equations can well predict the stress of the asphalt concrete surface layer, and elastic modulus of waterproof layer has a significant influence on stress values of asphalt concrete surface layer.

  18. Structural Impact of Construction Loads

    Science.gov (United States)

    2012-08-01

    Numerous bridge construction accidents have occurred across the country because of construction loadings, which are an underemphasized : topic in many DOT specifications and design manuals. Bridge girders are least stable when they are subjected to c...

  19. Field verification for the effectiveness of continuity diaphragms for skewed continuous P/C P/S concrete girder bridges : tech summary.

    Science.gov (United States)

    2009-10-01

    The majority of highway bridges are built as cast-in-place reinforced concrete slabs and prestressed concrete : girders. The simple-span precast, prestressed concrete girders made continuous through cast-in-place decks : and diaphragms have been wide...

  20. Active aerodynamic stabilisation of long suspension bridges

    DEFF Research Database (Denmark)

    Nissen, Henrik Ditlev; Sørensen, Paul Haase; Jannerup, Ole Erik

    2004-01-01

    The paper describes the addition of actively controlled appendages (flaps) attached along the length of the bridge deck to dampen wind-induced oscillations in long suppension bridges. A novel approach using control systems methods for the analysis of dynamic stability is presented. In order to make...... use of control analysis and design techniques, a linear model of the structural and aerodynamic motion around equilibriun is developed. The model is validated through comparison with finite element calculations and wind tunnel experimental data on the Great Belt East Bridge in Denmark. The developed...... active control scheme is local in that the flap control signal at a given longitudinal position along the bridge only depends on local motion measurements. The analysis makes use of the Nyquist stability criteria and an anlysis of the sensitivity function for stability analysis. The analysis shows...

  1. 23 CFR 650.807 - Bridges requiring a USCG permit.

    Science.gov (United States)

    2010-04-01

    ... improvement or construction of a bridge over navigable waters except for the exemption exercised by FHWA in... 23 Highways 1 2010-04-01 2010-04-01 false Bridges requiring a USCG permit. 650.807 Section 650.807... BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.807 Bridges requiring a USCG...

  2. Cone calorimeter tests of wood-based decking materials

    Science.gov (United States)

    Robert H. White; Mark A. Dietenberger; Nicole M. Stark

    2007-01-01

    New technologies in building materials have resulted in the use of a wide variety of materials in decks. As part of our effort to address fire concerns in the wildland-urban interface, the Forest Products Laboratory has been examining the fire performance of decking products. In addition to preservative-treated wood, decking products include wood-plastic composites and...

  3. 46 CFR 69.111 - Between-deck tonnage.

    Science.gov (United States)

    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 the... successively “1”, “2”, and so forth beginning at the bow. (4) Multiply the even numbered breadths by four and...

  4. Track-Bridge Longitudinal Interaction of Continuous Welded Rails on Arch Bridge

    Directory of Open Access Journals (Sweden)

    Rong Chen

    2013-01-01

    Full Text Available Taking arch bridges, including deck, half-through, and through arch bridges (short for DAB, HTAB, and TAB as examples, mechanics analysis models of longitudinal interaction between continuously welded rails (short for CWRs and arch bridges are established. Based on the finite element method (FEM, the longitudinal interaction calculation software of CWR on arch bridges has been developed. Focusing on an HTAB, the tension, compression, and deflection conditions are calculated and analyzed. The results show that the mechanics analysis models of three types of arch bridges can truly reflect the real state of the structure; the calculation software can be used for systematic research of the CWR on arch bridge; as for HTAB, temperature difference of arch rib has a small effect on rail tension/compression, and arch bridge can be simplified as a continuous beam for rail tension/compression additional force calculation; in calculation of deflection conditions of HTAB, it is suggested that train loads are arranged on half span and full span and take the direction of load entering bridge into account. Additionally, the deflection additional force variation of CFST basket handle arch bridge is different from that of ordinary bridge.

  5. Kinetic bridges.

    Science.gov (United States)

    1980-01-01

    This report on kinetic bridges is essentially a state-of-the-art study on two types of bridges whose location or physical characteristics are designed to be time dependent. The first type, called a "relocatable bridge", is essentially for use as a te...

  6. Experimental and finite element study of ultimate strength of continuous composite concrete slabs with steel decking

    Science.gov (United States)

    Gholamhoseini, Alireza

    2018-02-01

    Composite one-way concrete slabs with profiled steel decking as permanent formwork are commonly used in the construction industry. The steel decking supports the wet concrete of a cast in situ reinforced or post-tensioned concrete slab and, after the concrete sets, acts as external reinforcement. In this type of slab, longitudinal shear failure between the concrete and the steel decking is the most common type of failure at the ultimate load stage. Design codes require the experimental evaluation of the ultimate load capacity and longitudinal shear strength of each type of steel decking using full-scale tests on simple-span slabs. There is also no procedure in current design codes to evaluate the ultimate load capacity and longitudinal shear strength of continuous composite slabs and this is often assessed experimentally by full-scale tests. This paper presents the results of three full-scale tests up to failure on continuous composite concrete slabs cast with trapezoidal steel decking profile (KF70) that is widely used in Australia. Slab specimens were tested in four-point bending at each span with shear spans of span/4. The longitudinal shear failure of each slab is evaluated and the measured mid-span deflection, the end slip and the mid-span steel and concrete strains are also presented and discussed. Redistribution of bending moment in each slab is presented and discussed. A finite element model is proposed and verified by experimental data using interface element to model the bond properties between steel decking and concrete slab and investigate the ultimate strength of continuous composite concrete slabs.

  7. Experimental and finite element study of ultimate strength of continuous composite concrete slabs with steel decking

    Science.gov (United States)

    Gholamhoseini, Alireza

    2018-03-01

    Composite one-way concrete slabs with profiled steel decking as permanent formwork are commonly used in the construction industry. The steel decking supports the wet concrete of a cast in situ reinforced or post-tensioned concrete slab and, after the concrete sets, acts as external reinforcement. In this type of slab, longitudinal shear failure between the concrete and the steel decking is the most common type of failure at the ultimate load stage. Design codes require the experimental evaluation of the ultimate load capacity and longitudinal shear strength of each type of steel decking using full-scale tests on simple-span slabs. There is also no procedure in current design codes to evaluate the ultimate load capacity and longitudinal shear strength of continuous composite slabs and this is often assessed experimentally by full-scale tests. This paper presents the results of three full-scale tests up to failure on continuous composite concrete slabs cast with trapezoidal steel decking profile (KF70) that is widely used in Australia. Slab specimens were tested in four-point bending at each span with shear spans of span/4. The longitudinal shear failure of each slab is evaluated and the measured mid-span deflection, the end slip and the mid-span steel and concrete strains are also presented and discussed. Redistribution of bending moment in each slab is presented and discussed. A finite element model is proposed and verified by experimental data using interface element to model the bond properties between steel decking and concrete slab and investigate the ultimate strength of continuous composite concrete slabs.

  8. Improving bridges with prefabricated precast concrete systems.

    Science.gov (United States)

    2013-12-01

    In order to minimize the impact of construction on the traveling public, MDOT utilizes innovative and specialized construction methods such as Accelerated Bridge Construction (ABC). Michigan, like other highway agencies in the region, has several cha...

  9. Life-cycle assessment of redwood decking in the United States with a comparison to three other decking materials

    Science.gov (United States)

    R. Bergman; H. Sup-Han; E. Oneil; I. Eastin

    2013-01-01

    The goal of the study was to conduct a life-cycle inventory (LCI) of California redwood (Sequoia sempervirens) decking that would quantify the critical environmental impacts of decking from cradle to grave. Using that LCI data, a life-cycle assessment (LCA) was produced for redwood decking. The results were used to compare the environmental footprint...

  10. Structural Impact of Construction Loads : [Technical Summary

    Science.gov (United States)

    2012-01-01

    Numerous bridge construction accidents have occurred because of construction loadings, which are an underemphasized topic in many specifications and design manuals. Bridge girders are least stable during the construction phase, so it is important for...

  11. Analysis of the state of the art of precast concrete bridge substructure systems.

    Science.gov (United States)

    2013-10-01

    Precasting of bridge substructure components holds potential for accelerating the construction of bridges,reducing : impacts to the traveling public on routes adjacent to construction sites, improving bridge durability and hence service : life, and r...

  12. Social psychology on the flight deck

    Science.gov (United States)

    Helmreich, R. L.

    1980-01-01

    Social psychological and personality factors that can influence resource management on the flight deck are discussed. It is argued that personality and situational factors intersect to determine crew responses and that assessment of performance under full crew and mission conditions can provide the most valuable information about relevant factors. The possibility of training procedures to improve performance on these dimensions is discussed.

  13. Deck Yourself with Flu Protection Song

    Centers for Disease Control (CDC) Podcasts

    2009-12-22

    This song (sung to the tune of Deck the Halls) describes actions you can take to protect yourself and others from the flu. Sing along!  Created: 12/22/2009 by National Center for Preparedness, Detection, and Control of Infectious Diseases (NCPDCID), Division of Global Migration and Quarantine (DGMQ).   Date Released: 12/22/2009.

  14. Development of LRFD procedures for bridge pile foundations in Iowa - volume III : recommended resistance factors with consideration of construction control and setup.

    Science.gov (United States)

    2012-02-01

    The Federal Highway Administration (FHWA) mandated utilizing the Load and Resistance Factor Design (LRFD) approach for all new bridges initiated in the United States after October 1, 2007. As a result, there has been a progressive move among state De...

  15. Load Distribution Factors for Composite Multicell Box Girder Bridges

    Science.gov (United States)

    Tiwari, Sanjay; Bhargava, Pradeep

    2017-12-01

    Cellular steel section composite with a concrete deck is one of the most suitable superstructures in resisting torsional and warping effects induced by highway loading. This type of structure has inherently created new design problems for engineers in estimating its load distribution when subjected to moving vehicles. Indian Codes of Practice does not provide any specific guidelines for the design of straight composite concrete deck-steel multi-cell bridges. To meet the practical requirements arising during the design process, a simple design method is needed for straight composite multi-cell bridges in the form of load distribution factors for moment and shear. This work presents load distribution characteristics of straight composite multi-cell box girder bridges under IRC trains of loads.

  16. Noise from Aft Deck Exhaust Nozzles: Differences in Experimental Embodiments

    Science.gov (United States)

    Bridges, James E.

    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.

  17. Passive Control System for Mitigation of Longitudinal Buffeting Responses of a Six-Tower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Fangfang Geng

    2016-01-01

    Full Text Available This paper presents an investigation of mitigation of longitudinal buffeting responses of the Jiashao Bridge, the longest multispan cable-stayed bridge in the world. A time-domain procedure for analyzing buffeting responses of the bridge is implemented in ANSYS with the aeroelastic effect included. The characteristics of longitudinal buffeting responses of the six-tower cable-stayed bridge are studied in some detail, focusing on the effects of insufficient longitudinal stiffness of central towers and partially longitudinal constraints between the bridge deck and part of bridge towers. The effectiveness of viscous fluid dampers on the mitigation of longitudinal buffeting responses of the bridge is further investigated and a multiobjective optimization design method that uses a nondominating sort genetic algorithm II (NSGA-II is used to optimize parameters of the viscous fluid dampers. The results of the parametric investigations show that, by appropriate use of viscous fluid dampers, the top displacements of central towers and base forces of bridge towers longitudinally restricted with the bridge deck can be reduced significantly, with hampering the significant gain achieved in the base forces of bridge towers longitudinally unrestricted with the bridge deck. And the optimized parameters for the viscous fluid dampers can be determined from Pareto-optimal fronts using the NSGA-II that can satisfy the desired performance requirements.

  18. New conceptual design of portable bamboo bridge for emergency purposes

    Science.gov (United States)

    Musthaffa, A. A.; Nor, N. M.; Yusof, M. A.; Yuhazri, M. Y.

    2018-02-01

    Portable bridges serve as routes for troops during the military operations and the disaster relief operation. Nowadays, bamboo has been regarded as one of the alternative construction materials for building and bridge structures. This paper presents the conceptual design of the portable bridge. Several types of portable bridges and bamboo bridges are reviewed in the current work. The characteristics, capability and method of construction of each bridge are discussed. Finally, the conceptual of the portable bamboo bridge for emergency purposes is presented. The idea of producing portable bridge is proposed in the current work as it is crucial for providing route for communities affected by natural disasters.

  19. Polymer concrete overlay on the Big Swan Creek Bridge : interim report no. 1--installation and initial condition of overlay.

    Science.gov (United States)

    1984-01-01

    The installation of a thin polymer concrete overlay on the Big Swan Creek Bridge provides further evidence that an overlay of low permeability can be soundly bonded to a concrete bridge deck by maintenance forces with a minimum of disruption to traff...

  20. Thermal analysis of GFRP-reinforced continuous concrete decks subjected to top fire

    Science.gov (United States)

    Hawileh, Rami A.; Rasheed, Hayder A.

    2017-12-01

    This paper presents a numerical study that investigates the behavior of continuous concrete decks doubly reinforced with top and bottom glass fiber reinforced polymer (GFRP) bars subjected to top surface fire. A finite element (FE) model is developed and a detailed transient thermal analysis is performed on a continuous concrete bridge deck under the effect of various fire curves. A parametric study is performed to examine the top cover thickness and the critical fire exposure curve needed to fully degrade the top GFRP bars while achieving certain fire ratings for the deck considered. Accordingly, design tables are prepared for each fire curve to guide the engineer to properly size the top concrete cover and maintain the temperature in the GFRP bars below critical design values in order to control the full top GFRP degradation. It is notable to indicate that degradation of top GFRP bars do not pose a collapse hazard but rather a serviceability concern since cracks in the negative moment region widen resulting in simply supported spans.

  1. GFRP seismic strengthening and structural heath monitoring of Portage Creek Bridge concrete columns

    International Nuclear Information System (INIS)

    Huffman, S.; Bagchi, A.; Mufti, A.; Neale, K.; Sargent, D.; Rivera, E.

    2006-01-01

    Located in Victoria British Columbia (BC), Canada, the Portage Creek Bridge is a 124m long, three-span structure with a reinforced concrete piers and abutments on H piles. The bridge was designed prior to the introduction of current bridge seismic design codes and construction practices. Therefore it was not designed to resist the earthquake forces as required by today's standards. The bridge is on a route classified as a Municipal Disaster Route scheduled to be retrofitted to prevent collapse during a design seismic event, with a return period of 475 years (i.e., an event with 105 probability of exceedance in 50 years). Conventional materials and methods were used to retrofit most of the bridge. The dynamic analysis of the bridge predicted the two tall columns of Pier No. 1 will form plastic hinges under an earthquake resulting an additional shear to the short columns of Pier No. 2. A non-liner static pushover analysis indicated the short columns will not be able to form plastic hinges prior to failure in shear. The innovative solution of Fiber Reinforced Polymer wraps (FRPs) was chosen to strengthen the short columns for shear without increasing the moment capacity. The FRP wraps and the bridge were instrumented as one of 36 demonstration projects across Canada sponsored by ISIS (Intelligent Sensing for Innovative Structure) Canada, federally funded Network of Centers of Excellence, to access the performance of FRP and the use of FOS (Fiber Optic Sensors) for Structural Health Monitoring (SHM). The two columns of the bridge pier were strengthened with GFRP (Glass Fiber Reinforced Polymer) wraps with eight bi-directional rosette type strain gauges and four long gauge fiber optic sensors attached to the outer layer of the wraps. In addition, two 3-D Crossbow accelerometers are installed on the pier cap above the columns and a traffic web-cam mounted above the deck at the pier location. The data is collected through high sped internet line to an interactive web page

  2. Building Bridges One Line at a Time

    Science.gov (United States)

    Grigsby, Cathy Murray

    2012-01-01

    In this article, first-grade students were taught the different kinds of lines that were part of the construction of various bridges--the curved lines of the arches of stone bridges, straight lines connecting the cables of a suspension bridge, vertical lines, horizontal lines, and so on. They gained practice in drawing structures and in fine brush…

  3. Myocardial Bridging

    Directory of Open Access Journals (Sweden)

    Shi-Min Yuan

    2016-02-01

    Full Text Available Abstract Myocardial bridging is rare. Myocardial bridges are most commonly localized in the middle segment of the left anterior descending coronary artery. The anatomic features of the bridges vary significantly. Alterations of the endothelial morphology and the vasoactive agents impact on the progression of atherosclerosis of myocardial bridging. Patients may present with chest pain, myocardial infarction, arrhythmia and even sudden death. Patients who respond poorly to the medical treatment with β-blockers warrant a surgical intervention. Myotomy is a preferred surgical procedure for the symptomatic patients. Coronary stent deployment has been in limited use due to the unsatisfactory long-term results.

  4. An Expert System for Concrete Bridge Management

    DEFF Research Database (Denmark)

    Brito, J. de; Branco, F. A.; Thoft-Christensen, Palle

    1997-01-01

    management systems are presently being implemented by bridge authorities in several countries. The prototype of an expert system for concrete bridge management is presented in this paper, with its functionality relying on two modules. The inspection module relies on a periodic acquisition of field......The importance of bridge repair versus new bridge construction has risen in recent decades due to high deterioration rates that have been observed in these structures. Budgets both for building new bridges and keeping the existing ones are always limited. To help rational decision-making, bridge...

  5. Investigation of Influence Factors of Wind-Induced Buffeting Response of a Six-Tower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Zhi-Qiang Zhang

    2016-01-01

    Full Text Available This paper presents an investigation of the wind-induced buffeting responses of the Jiashao Bridge, the longest multispan cable-stayed bridge in the world. A three-dimensional finite element model for the Jiashao Bridge is established using the commercial software package ANSYS and a 3D fluctuating wind field is simulated for both bridge deck and towers. A time-domain procedure for analyzing buffeting responses of the bridge is implemented in ANSYS with the aeroelastic effect included. The characteristics of buffeting responses of the six-tower cable-stayed bridge are studied in some detail, focusing on the effects including the difference in the longitudinal stiffness between the side towers and central towers, partially longitudinal constraints between the bridge deck and part of bridge towers, self-excited aerodynamic forces, and the rigid hinge installed in the middle of the bridge deck. The analytical results can provide valuable references for wind-resistant design of multispan cable-stayed bridges in the future.

  6. Linguistic Barriers and Bridges

    DEFF Research Database (Denmark)

    Thuesen, Frederik

    2016-01-01

    The influence of language on social capital in low-skill and ethnically diverse workplaces has thus far received very limited attention within the sociology of work. As the ethnically diverse workplace is an important social space for the construction of social relations bridging different social...... and intercultural communication, this article analyses interviews with 31 employees from two highly ethnically diverse Danish workplaces. The article shows how linguistic barriers such as different levels of majority language competence and their consequent misunderstandings breed mistrust and hostility, whilst...... communication related to collaboration and ‘small talk’ may provide linguistic bridges to social capital formation....

  7. 46 CFR 28.565 - Water on deck.

    Science.gov (United States)

    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 28...

  8. 46 CFR 91.55-5 - Plans and specifications required for new construction.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Plans and specifications required for new construction... new construction. (a) General. (1) Specifications. (2) General Arrangement Plan of decks, holds, inner... Watertight Decks. (11) *Details of Hinged Subdivision Watertight Doors and Operating Gear. (12) *Scuppers and...

  9. Design of wireless synchronous structural monitoring system for large bridges

    Science.gov (United States)

    Liu, Zhiqiang; Liu, Wei; Li, Na; Yu, Yan; Mao, Xingquan; Yang, Zhitao

    2017-04-01

    Large bridges play a significant role in the development of both the urban traffic condition and the social economy. It is of high importance to monitor the operational bridges and to assess their security from the perspective of people's life and property safety. In this paper, a wireless bridge structure monitoring system was developed and DMTS synchronization algorithm (based on the one-way synchronization mechanism of the sender) which can meet the system requirement was proposed. Then the deck vibration test of a bridge in Xiamen was carried out. The study shows that the wireless sensing system has the advantage of high accuracy, and the feature of easy operation, good instantaneity, and low overhead costs, which has a good application prospect in the field of structure monitoring and condition assessment of the bridges.

  10. Istanbul Bridge Conference 2014

    CERN Document Server

    Gülkan, Polat; Mahmoud, Khaled

    2016-01-01

      The book includes peer-reviewed contributions selected from presentations given at the Istanbul Bridge Conference 2014, held from August 11 – 13 in Istanbul, Turkey. It reports on the current challenges in bridge engineering faced by professionals around the globe, giving a special emphasis to recently developed techniques, innovations and opportunities. The book covers key topics in the field, including modeling and analysis methods; construction and erection techniques; design for extreme events and condition assessment and structural health monitoring. There is a balanced presentation of theory, research and practice. This book, which provides the readers with a comprehensive and timely reference guide on current practices in bridge engineering, is intended for professionals, academic researchers and students alike.

  11. Precast alternative for flat slab bridges : final report.

    Science.gov (United States)

    2013-10-26

    The cast-in-place (CIP) concrete slab bridge and the hollow core flat slab bridge are two very common bridge types utilized by the : South Carolina Department of Transportation (SCDOT). The CIP bridge is durable but has a long construction time while...

  12. 46 CFR 108.235 - Construction.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 4 2010-10-01 2010-10-01 false Construction. 108.235 Section 108.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) A-MOBILE OFFSHORE DRILLING UNITS DESIGN AND EQUIPMENT Construction and Arrangement Helicopter Facilities § 108.235 Construction. (a) Each helicopter deck must be...

  13. Bridge Management Systems

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle

    In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way.......In this paper bridge management systems are discussed with special emphasis on management systems for reinforced concrete bridges. Management systems for prestressed concrete bridges, steel bridges, or composite bridges can be developed in a similar way....

  14. Bearing capacity of prestressed concrete decks slabs

    NARCIS (Netherlands)

    Amir, S.; Van der Veen, C.; Walraven, J.C.; De Boer, A.

    2014-01-01

    In the Netherlands, most of the bridges were built more than 50 years ago and it is essential for designers to find out if these bridges are safe for modern traffic especially in shear since that was not considered in design recommendations before 1976. Detailed experiments have been carried out in

  15. A novel non-bridging external fixator construct versus volar angular stable plating for the fixation of intra-articular fractures of the distal radius--a biomechanical study.

    Science.gov (United States)

    Windolf, Markus; Schwieger, Karsten; Ockert, Ben; Jupiter, Jesse B; Gradl, Georg

    2010-02-01

    Non-bridging external fixation has recently been introduced as an alternative to volar angular stable plating for the fixation of unstable intra-articular distal radial fractures. The purpose of this study was to biomechanically compare a new non-bridging external fixator construct to volar angular stable plate fixation in a dorsally comminuted intra-articular fracture model of the distal radius. Five pairs of fresh frozen human cadaveric radii were randomly supplied with either a non-bridging external fixator or a stainless steel volar locking plate. A three-fragmental AO 23-C2.1 fracture was created by removing a 15 degrees dorsal wedge with remaining volar cortical contact and by an intra-articular osteotomy lateral to the lister-tubercle. Physiological load transfer via the wrist was simulated by means of a custom-made seesaw. For biomechanical testing, the bones were loaded in cyclic axial compression. Starting at 100N, the load was monotonically increased at 0.025 degrees N per cycle until failure of the construct. Motion of the lunate and scaphoid fragments with respect to the radial diaphysis was acquired by optical three-dimensional (3D) motion tracking. Plastic wedge deformation was determined after 2000, 4000 and 6000 cycles. The amplitude of wedge motion at the beginning of the test as a measure for construct stiffness was significantly lower for the fixator group (P=0.003, power=0.99). Plastic wedge deformation after 2000, 4000 and 6000 cycles was found significantly lower for the external fixator (repeated measures analysis of variance (ANOVA), P=0.009, power=0.86). Displacement of the intra-articular gap was found below 0.6mm (mean) for both groups (P>0.05). The study revealed superior biomechanical properties of the proposed non-bridging external fixation compared to volar locked plating in an unstable intra-articular fracture model with volar cortical support. However, both fixation techniques seem to apply sufficient stabilisation to restore and

  16. Dynamic Analysis of Horizontally Curved Thin-Walled Box-Girder Bridge due to Moving Vehicle

    Directory of Open Access Journals (Sweden)

    K. Nallasivam

    2007-01-01

    Full Text Available The impact on curved box-girder bridges due to vehicle moving across rough bridge deck have been analyzed using bridge-vehicle coupled dynamics. The bridge deck unevenness has been assumed to be a homogeneous random process in space specified by a PSD function. The analysis incorporates the effect of centrifugal forces due to vehicle moving on curved bridge. The curved box-girder bridge has been numerically modeled using computationally efficient thin-walled box-beam finite elements which take into account the torsional warping, distortion and distortional warping, that are important features of thin-walled box girders. Rigid vehicle with longitudinal and transverse input to the wheels giving rise to heave-pitch-roll degrees of freedom has been considered. The theoretical bridge model used in simulation study has been validated by a free vibration experiment using impact excitation. The impact factors for several response parameters such as bending moment, shear force, torsional moment, torsional bi-moment, distortional moment, distortional bi-moment and vertical deflections have been obtained for various bridge-vehicle parameters. Both constant velocity and forward acceleration of the vehicle have been considered to examine impact factor. The results highlighted that the impact factors of a curved box girder bridge corresponding to torsion, distortion and their corresponding bimoments have been observed to be generally very high, while those of the other responses are also relatively higher than that of corresponding straight box girder bridge.

  17. Multiobjective Optimal Control of Longitudinal Seismic Response of a Multitower Cable-Stayed Bridge

    Directory of Open Access Journals (Sweden)

    Geng Fangfang

    2016-01-01

    Full Text Available The dynamic behavior of a multitower cable-stayed bridge with the application of partially longitudinal constraint system using viscous fluid dampers under real earthquake ground motions is presented. The study is based on the dynamic finite element model of the Jiashao Bridge, a six-tower cable-stayed bridge in China. The prime aim of the study is to investigate the effectiveness of viscous fluid dampers on the longitudinal seismic responses of the bridge and put forth a multiobjective optimization design method to determine the optimized parameters of the viscous fluid dampers. The results of the investigations show that the control objective of the multitower cable-stayed bridge with the partially longitudinal constraint system is to yield maximum reductions in the base forces of bridge towers longitudinally restricted with the bridge deck, with slight increases in the base forces of bridge towers longitudinally unrestricted with the bridge deck. To this end, a multiobjective optimization design method that uses a nondominating sort genetic algorithm II (NSGA-II is used to optimize parameters of the viscous fluid dampers. The effectiveness of the proposed optimization design method is demonstrated for the multitower cable-stayed bridge with the partially longitudinal constraint system, which reveals that a design engineer can choose a set of proper parameters of the viscous fluid dampers from Pareto optimal fronts that can satisfy the desired performance requirements.

  18. Construction of halide-bridged tungsten-copper-sulfide double cubanelike clusters from a new precursor [(Tp*WS2)2(μ-S2)].

    Science.gov (United States)

    Wei, Li-Pei; Ren, Zhi-Gang; Zhu, Lian-Wen; Yan, Wen-Yan; Sun, Sha; Wang, Hui-Fang; Lang, Jian-Ping; Sun, Zhen-Rong

    2011-05-16

    Treatment of [Et(4)N][Tp*WS(3)] (1) (Tp* = hydridotris(3,5-dimethylpyrazol-1-yl)borate) with 2 equiv of AgSCN in MeCN afforded a novel neutral compound [(Tp*WS(2))(2)(μ-S(2))] (2). Reactions of 2 with excess CuX (X = Cl, Br, I) in MeCN and CH(2)Cl(2) or CHCl(3) formed three neutral W/Cu/S clusters [{Tp*W(μ(3)-S)(3)Cu(3)(μ-Cl)}(2)Cu(μ-Cl)(2)(μ(7)-Cl)(MeCN)](2) (3), [{Tp*W(μ(3)-S)(3)Cu(3)}(2)Br(μ-Br)(2)(μ(4)-Br)(MeCN)] (4), and [{Tp*W(μ(3)-S)(3)Cu(3)}(2){Cu(2)(μ-I)(4)(μ(3)-I)(2)}] (5), respectively. On the other hand, treatment of 2 with CuX (X = Cl, Br) in the presence of Et(4)NX (X = Cl, Br) produced two anionic W/Cu/S clusters [Et(4)N][{Tp*W(μ(3)-S)(3)Cu(3)X}(2)(μ-X)(2)(μ(4)-X)] (6: X = Cl; 7 X = Br). Compounds 2-7 were characterized by elemental analysis, IR, UV-vis, (1)H NMR, electrospray ionization (ESI) mass spectra, and single-crystal X-ray crystallography. The dimeric structure of 2 can be viewed as two [Tp*WS(2)] fragments in which two W atoms are connected by one S(2)(2-) dianion. Compounds 3-7 all possess unique halide-bridged double cubanelike frameworks. For 3, two [Tp*W(μ(3)-S)(3)Cu(3)](2+) dications are linked via a μ(7)-Cl(-) bridge, two μ-Cl(-) bridges, and a [Cu(MeCN)(μ-Cl)(2)](+) bridge. For 4, one [Tp*W(μ(3)-S)(3)Cu(3)(MeCN)](2+) dication and one [Tp*W(μ(3)-S)(3)Cu(3)Br](+) cation are linked via a μ(4)-Br(-) and two μ-Br(-) bridges. For 5, the two [Tp*W(μ(3)-S)(3)Cu(3)](2+) dications are bridged by a linear [(μ-I)(2)Cu(μ(3)-I)(2)Cu(μ-I)(2)](4+) species. For 6 and 7, two [Tp*W(μ(3)-S)(3)Cu(3)X](+) cations are linked by a μ(4)-X(-) and two μ-X(-) bridges (X = Cl, Br). In addition, the third-order nonlinear optical (NLO) properties of 2-7 in MeCN/CH(2)Cl(2) were investigated by using femtosecond degenerate four-wave mixing (DFWM) technique.

  19. Probabilistic Corrosion Service Life Model of Concrete Bridge Exposed to Chloride Deicer Salts

    Directory of Open Access Journals (Sweden)

    Cristian-Claudiu Comisu

    2005-01-01

    Full Text Available A model to determine the time till first repair and subsequent rehabilitation of concrete bridge decks exposed to chloride deicer salts that recognizes and incorporates the statistical nature of factors affecting the corrosion process, consists of the following serial phases: diffusion to the depth of the steel that would precipitate first maintenance actions; corrosion of the steel at the first maintenance depth until cracking and spalling occurs; continuous spalling until a damage level is reached which is defined as the end of functional service life for the deck of concrete bridge. The model expands on an existing deterministic model using statistical computing techniques, including resampling techniques such as the parametric and simple bootstrap. Emphasis was placed on the diffusion portion of the diffusion-cracking model, but advances can be readily included for the time for corrosion deterioration after corrosion initiation. The diffusion phase is described by Fick’s law and the boundary conditions define the solution form. The time till cracking model depends upon some factors as concrete strength properties, cover depth and corrosion rate. Corrosion rate has a significant influence on the time to cracking which typically occurs in three to seven years after initiation. Service life model that predict the time to first repair and rehabilitation of concrete bridge decks provide a useful tool for comparing the effectiveness measures and provide bridge engineers with a useful planning tool. A service life model for the corrosion of concrete bridge deck in chloride laden environments is proposed. The aim of this paper is to enhance the awareness among the engineering community to use the model to determine the time till first repair and subsequent rehabilitation of concrete bridge decks exposed to chloride deicer salts in Romania.

  20. Below Decks Electromagnetic Survey Study - Phase 1.

    Science.gov (United States)

    1982-08-06

    Coupling Model 11 4-1 Predicted and Measured P.Jdiated Field from Port Whip on FFG-7 Class Ships at SGSI 15 4-2 Predicted and Measured Radiated Fields...TABLES Page 4-1 Predicted Field Levels to the SGSI from the Port Transmit Whip Above and Below Decks on the FFG-? Class 16 4-2 Predicted Field Levels...Indicator ( SGSI ) from the port transmit 35’ whip antenna. The purpose of these measurements were to define the radiated field at the SGSI so that EMI fixes

  1. 29 CFR 1915.165 - Ship's deck machinery.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Ship's deck machinery. 1915.165 Section 1915.165 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) OCCUPATIONAL SAFETY AND HEALTH STANDARDS FOR SHIPYARD EMPLOYMENT Ship's Machinery and Piping Systems § 1915.165 Ship's deck machiner...

  2. 46 CFR 69.109 - Under-deck tonnage.

    Science.gov (United States)

    2010-10-01

    ... is divided into an even number of equal parts as indicated in the following table: Class Tonnage... tonnage deck for an open vessel is the upper edge of the upper strake. Depths of transverse sections are..., if the distance between the line of its tonnage deck and the upper edge of the upper strake is more...

  3. Sprinkling to prevent decay in decked western hemlock logs.

    Science.gov (United States)

    Ernest Wright; A.C. Knauss; R.M. Lindgren

    1959-01-01

    Decay developing in decked western hemlock (Tsuga heterophylla) has caused considerable loss in pulp yields in the Pacific Northwest. The Oregon Pulp and Paper Co., which commonly decks hemlock logs through one summer and occasionally through two summers, cooperated with the Pacific Northwest Forest and Range Experiment Station in a study to...

  4. Evaluating spent CCA residential decks for second-life products

    Science.gov (United States)

    Robert Smith; David Bailey; Phil Araman

    2003-01-01

    The amount of CCA treated wood being removed from spent residential decks is increasing at a tremendous rate. While most spent CCA treated wood is being disposed in landfills, further useful and environmentally beneficial alternatives have to be met. This research estimated the percentage of recoverable lumber from spent CCA decks that can be recycled into other usable...

  5. Reliability Assessment of Long Span Suspension Bridges Subjected to Dead Loads

    OpenAIRE

    Antonsen, Kristin

    2016-01-01

    In the present study the influence of standardized safety factors in large and heavy structures, where the major loading arises from self-weight of the structure itself, is considered. For this purpose, a reliability analysis of the Hardanger Bridge is performed. The loading is assumed to originate from the self-weight of the bridge deck, hangers and main cables only, i.e. all other loads are neglected. The reliability analysis is performed by comparing axial loading and resistance capaci...

  6. A Novel Concrete-Based Sensor for Detection of Ice and Water on Roads and Bridges

    OpenAIRE

    Tabatabai, Habib; Aljuboori, Mohammed

    2017-01-01

    Hundreds of people are killed or injured annually in the United States in accidents related to ice formation on roadways and bridge decks. In this paper, a novel embedded sensor system is proposed for the detection of black ice as well as wet, dry, and frozen pavement conditions on roads, runways, and bridges. The proposed sensor works by detecting changes in electrical resistance between two sets of stainless steel poles embedded in the concrete sensor to assess surface and near-surface cond...

  7. National Bridge Inventory (NBI) Bridges

    Data.gov (United States)

    Department of Homeland Security — The NBI is a collection of information (database) describing the more than 600,000 of the Nation's bridges located on public roads, including Interstate Highways,...

  8. Laboratory investigation of grouted coupler connection details for ABC bridge projects.

    Science.gov (United States)

    2015-08-01

    With an ever increasing desire to utilize accelerated bridge construction (ABC) techniques, it is becoming critical that bridge : designers and contractors have confidence in typical details. The Keg Creek Bridge on US 6 in Iowa was a recent ABC exam...

  9. NHDOT : process for municipally-managed state bridge aid program projects

    Science.gov (United States)

    2007-09-12

    The document sets for the requirements for a municipality which to manage the design and construction of a bridge rehabilitation or replacement project and receive Bridge Aid under the applicable provisions of RSA 234. Bridge Aid provided to a Munici...

  10. Critique of the Reggeized deck model

    International Nuclear Information System (INIS)

    Berger, E.L.

    1975-01-01

    A detailed analysis is presented of the Reggeized pion exchange Deck model for processes of the type ap → A*N → (a*π)N, where a = π, K, or nucleon and a* = rho, K*, N or Δ. Predictions of the model for both production and decay properties of the low mass system A* → (a*π) are derived and contrasted with data. Diffractive as well as charge exchange reactions are treated. The role of pion exchange in generating (a*π) enhancements near threshold and their properties is examined from several points of view. Characteristic exchange effects and quantum number properties (e.g., cross-overs) of the pion exchange Deck graph are shown to be verified in the data, but this graph alone is inadequate. The failures all point to the need for a second graph, having a* exchange properties. The contribution of a* exchange is roughly equal to that of the π exchange graph. (U.S.)

  11. A Polish approach to FRP bridges

    Science.gov (United States)

    Siwowski, Tomasz; Rajchel, Mateusz

    2017-12-01

    The paper presents initial results of a new approach to FRP composite bridge construction that is presently being developed and tested in Poland. The concept combines lightweight concrete with FRP composites to create a durable highly optimised structure. The paper describes the bridge system itself and presents the research results on its development. The basic design is presented together with research results on its development: FEM analysis and a range of static test results of full-scale bridge beam experiments. The paper finishes with some test results of a full scale bridge that was constructed near Rzeszow in December 2015.

  12. A new multiconstraint method for determining the optimal cable stresses in cable-stayed bridges.

    Science.gov (United States)

    Asgari, B; Osman, S A; Adnan, A

    2014-01-01

    Cable-stayed bridges are one of the most popular types of long-span bridges. The structural behaviour of cable-stayed bridges is sensitive to the load distribution between the girder, pylons, and cables. The determination of pretensioning cable stresses is critical in the cable-stayed bridge design procedure. By finding the optimum stresses in cables, the load and moment distribution of the bridge can be improved. In recent years, different research works have studied iterative and modern methods to find optimum stresses of cables. However, most of the proposed methods have limitations in optimising the structural performance of cable-stayed bridges. This paper presents a multiconstraint optimisation method to specify the optimum cable forces in cable-stayed bridges. The proposed optimisation method produces less bending moments and stresses in the bridge members and requires shorter simulation time than other proposed methods. The results of comparative study show that the proposed method is more successful in restricting the deck and pylon displacements and providing uniform deck moment distribution than unit load method (ULM). The final design of cable-stayed bridges can be optimised considerably through proposed multiconstraint optimisation method.

  13. Seismic Response Analysis of Continuous Multispan Bridges with Partial Isolation

    Directory of Open Access Journals (Sweden)

    E. Tubaldi

    2015-01-01

    Full Text Available Partially isolated bridges are a particular class of bridges in which isolation bearings are placed only between the piers top and the deck whereas seismic stoppers restrain the transverse motion of the deck at the abutments. This paper proposes an analytical formulation for the seismic analysis of these bridges, modelled as beams with intermediate viscoelastic restraints whose properties describe the pier-isolator behaviour. Different techniques are developed for solving the seismic problem. The first technique employs the complex mode superposition method and provides an exact benchmark solution to the problem at hand. The two other simplified techniques are based on an approximation of the displacement field and are useful for preliminary assessment and design purposes. A realistic bridge is considered as case study and its seismic response under a set of ground motion records is analyzed. First, the complex mode superposition method is applied to study the characteristic features of the dynamic and seismic response of the system. A parametric analysis is carried out to evaluate the influence of support stiffness and damping on the seismic performance. Then, a comparison is made between the exact solution and the approximate solutions in order to evaluate the accuracy and suitability of the simplified analysis techniques for evaluating the seismic response of partially isolated bridges.

  14. Concrete-Filled Steel Tube Arch Bridges in China

    Directory of Open Access Journals (Sweden)

    Jielian Zheng

    2018-02-01

    Full Text Available In the past 20 years, great progress has been achieved in China in the construction of concrete-filled steel tube (CFST arch bridges and concrete arch bridges with a CFST skeleton. The span of these bridges has been increasing rapidly, which is rare in the history of bridge development. The large-scale construction of expressways and high-speed railways demands the development of long-span arch bridges, and advances in design and construction techniques have made it possible to construct such bridges. In the present study, the current status, development, and major innovative technologies of CFST arch bridges and concrete arch bridges with a CFST skeleton in China are elaborated. This paper covers the key construction technologies of CFST arch bridges, such as the design, manufacture, and installation of steel tube arch trusses, the preparation and pouring of in-tube concrete, and the construction of the world’s longest CFST arch bridge—the First Hejiang Yangtze River Bridge. The main construction technologies of reinforced concrete arch bridges are also presented, which include cable-stayed fastening-hanging cantilever assembly, adjusting the load by means of stay cables, surrounding the concrete for arch rib pouring, and so forth. In addition, the construction of two CFST skeleton concrete arch bridges—the Guangxi Yongning Yong River Bridge and the Yunnan–Guangxi Railway Nanpan River Bridge—is discussed. CFST arch bridges in China have already gained a world-leading position; with the continuous innovation of key technologies, China will become the new leader in promoting the development of arch bridges. Keywords: Concrete-filled steel tube (CFST arch bridge, Steel-reinforced concrete arch bridge, Cable-stayed fastening-hanging cantilever assembly, Vacuum-assisted pouring in-tube concrete, Adjusting load by stay cables

  15. Field performance of timber bridges. 11, Spearfish Creek stress-laminated box-beam bridge

    Science.gov (United States)

    J. P. Wacker; M. A. Ritter; K. Stanfill-McMillan

    The Spearfish Creek bridge was constructed in 1992 in Spearfish, South Dakota. It is a single-span, stress-laminated, box-beam superstructure. Performance of the bridge is being monitored for 5 years, beginning at installation. This report summarizes results for the first 3-1/2 years of monitoring and includes information on the design, construction, and field...

  16. 23 CFR 650.805 - Bridges not requiring a USCG permit.

    Science.gov (United States)

    2010-04-01

    ... permit is not required for bridge construction. This determination shall be made at an early stage of... 23 Highways 1 2010-04-01 2010-04-01 false Bridges not requiring a USCG permit. 650.805 Section 650... OPERATIONS BRIDGES, STRUCTURES, AND HYDRAULICS Navigational Clearances for Bridges § 650.805 Bridges not...

  17. Building Bridges

    DEFF Research Database (Denmark)

    The report Building Bridges adresses the questions why, how and for whom academic audience research has public value, from the different points of view of the four working groups in the COST Action IS0906 Transforming Audiences, Transforming Societies – “New Media Genres, Media Literacy and Trust...

  18. Bridging Anticoagulation

    Science.gov (United States)

    ... Procedure? The BRIDGE Study Investigators Download PDF https://doi.org/10.1161/CIRCULATIONAHA.111.084517 Circulation. 2012; 125: ... e496-e498 , originally published March 26, 2012 https://doi.org/10.1161/CIRCULATIONAHA.111.084517 Citation Manager Formats ...

  19. Crossing Bridges

    Indian Academy of Sciences (India)

    Perhaps we are not smart enough. How would we go about establishing that the problem has no solution? One possibility is to enumerate all possible ... Even if we do this for the bridges of Konigsberg, we would learn nothing about other similar situations. Consider for example the fictitious city of Lutetia at the confluence of.

  20. Ash-Based Building Panels Production and Demonstration of Aerock Decking Building Product

    International Nuclear Information System (INIS)

    Alan E. Bland; Jesse Newcomer

    2007-01-01

    Western Research Institute (WRI) of Laramie, Wyoming and AeRock, LLC of Eagar, Arizona (formerly of Bellevue, Washington) partnered, under sponsorship of the U.S. Department of Energy National Energy Technology Laboratory (U.S. DOE-NETL), to support the development of rapid-setting, ash-based, fiber-incorporated ''green'' building products. Green building materials are a rapidly growing trend in the building and construction industry in the US. A two phase project was implemented wherein Phase I assessed, through chemical and physical testing, ash, ash-based cement and fiber composites exhibiting superior structural performance when applied to the AeRock mixing and extrusion process and involved the conduct of pilot-scale production trials of AeRock products, and wherein Phase II involved the design, construction, and operation of a commercial-scale plant to confirm production issues and to produce panels for performance evaluations. Phase I optimized the composite ingredients including ash-based cement, Class F and Class C DFGD ash, and various fiber reinforcements. Additives, such as retardants and accelerators, were also evaluated as related to extruder performance. The optimized composite from the Phase I effort was characterized by a modulus of rupture (MOR) measured between 1,931 and 2,221 psi flexural strength, comparable to other wood and non-wood building materials. Continuous extrusion of the optimum composite in the AeRock pilot-scale facility produced an excellent product that was assembled into a demonstration for exhibit and durability purposes. Finishes, from plain to marbled, from bright reds to muted earth tones and with various textures, could easily be applied during the mixing and extrusion process. The successful pilot-scale demonstration was in turn used to design the production parameters and extruder dies for a commercial scale demonstration at Ultrapanel Pty, Ltd of Ballarat, Australia under Phase II. The initial commercial-scale production

  1. Public/Private Partnerships for New Construction.

    Science.gov (United States)

    Adams, Matthew C.

    1999-01-01

    Discusses how colleges can finance new construction projects during lean financial times by employing public/private partnerships in an off-balance sheet financing format. Construction planning of a new school parking deck is used to illustrate the process. Benefits of savings in operating costs, management fees, and other line-item expenses are…

  2. Super-light concrete decks for building floor slabs

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Castberg, Niels Andreas; Christensen, Jacob

    2014-01-01

    This paper presents investigations carried out at the Technical University of Denmark (DTU) on a prototype series for a super-lightweight prestressed concrete deck element called the SL-Deck. The intention behind making a new prefabricated deck element is to improve performance with respect...... the pull-out strength of prestressing wires, the fire resistance and the acoustic insulation. Based on the results of the investigations, recommendations are given for further development of the structure before fully automated mass production is established....

  3. Durability of lightweight concrete : Phase I : concrete temperature study.

    Science.gov (United States)

    1968-08-01

    This report describes a study conducted to determine the temperature gradient throughout the depth of a six inch concrete bridge deck. The bridge deck selected for study was constructed using lightweight concrete for the center spans and sand and gra...

  4. Trinidad Lake asphalt overlay performance : final report.

    Science.gov (United States)

    2014-07-01

    Construction of the new Tacoma Narrows Bridge (TNB) included a steel orthotropic bridge deck. : The higher flexibility of an orthotropic deck causes pavement placed upon it to fatigue and crack more : quickly than pavement placed on a normal roadway....

  5. Measurement of Deflection Line on Bridges

    Science.gov (United States)

    Urban, Rudolf; Štroner, Martin

    2013-12-01

    Prestressed concrete bridges are very sensitive to the increase in long-term deflections. Reliable forecasts of deflections of bridge structures during construction and durability are crucial for achieving good durability. The main results of measurements are the changes of the deflection line of the bridge structures, which places special demands on the measurement procedure. Results from measurements are very useful for the improvement of mathematical prediction methods of behaviour of long span prestressed concrete structures.

  6. Structural Behavior and Design of Barrier-Overhang Connection in Concrete Bridge Superstructures Using AASHTO LRFD Method

    Directory of Open Access Journals (Sweden)

    Byungik Chang

    2012-01-01

    Full Text Available The U.S. Departments of Transportation adopted the AASHTO LRFD Bridge Design Specifications during the year 2007, which is mandated by AASHTO and FHWA. The application of LRFD specification initiated numerous research works in this field. This investigation addresses the LRFD and Standard design methodologies of concrete deck slab, deck overhang, barrier and combined barrier-bridge overhang. The purpose of this study is to propose a simplified manual design approach for the barrier-deck overhang in concrete bridges. For concrete deck slab overhang and barrier, application of National Cooperative Highway Research Program crash test is reviewed. The failure mechanism, design philosophy and load cases including extreme event limit states for barrier and overhang are discussed. The overhang design for the combined effect of bending moment and axial tension is probably the most important part of the design process. The overhang might be a critical design point of the deck with significantly higher amount of reinforcement. The design process becomes complicated due to combined force effect, LRFD crash test level requirement and the existence of several load combinations. Using this program, different LRFD load combinations are plotted together with the interaction diagram and the design is validated.

  7. Assessment on transient sound radiation of a vibrating steel bridge due to traffic loading

    Science.gov (United States)

    Zhang, He; Xie, Xu; Jiang, Jiqing; Yamashita, Mikio

    2015-02-01

    Structure-borne noise induced by vehicle-bridge coupling vibration is harmful to human health and living environment. Investigating the sound pressure level and the radiation mechanism of structure-borne noise is of great significance for the assessment of environmental noise pollution and noise control. In this paper, the transient noise induced by vehicle-bridge coupling vibration is investigated by employing the hybrid finite element method (FEM) and boundary element method (BEM). The effect of local vibration of the bridge deck is taken into account and the sound responses of the structure-borne noise in time domain is obtained. The precision of the proposed method is validated by comparing numerical results to the on-site measurements of a steel girder-plate bridge in service. It implies that the sound pressure level and its distribution in both time and frequency domains may be predicted by the hybrid approach of FEM-BEM with satisfactory accuracy. Numerical results indicate that the vibrating steel bridge radiates high-level noise because of its extreme flexibility and large surface area for sound radiation. The impact effects of the vehicle on the sound pressure when leaving the bridge are observed. The shape of the contour lines in the area around the bridge deck could be explained by the mode shapes of the bridge. The moving speed of the vehicle only affects the sound pressure components with frequencies lower than 10 Hz.

  8. FEATURES OF DESIGN OF TIED-ARCH BRIDGES WITH FLEXIBLE INCLINED SUSPENSION HANGERS

    Directory of Open Access Journals (Sweden)

    V. O. Samosvat

    2017-10-01

    Full Text Available Purpose. Investigation and analysis of the hanger arrangement and the structural stability of a Network arch bridge – a tied-arch bridge with inclined hangers that cross each other at least twice. It is also necessary to make a comparative analysis with other types of hanger arrangements. Methodology. The authors in their research investigated a large number of parameters to determine their influence in the force distribution in the arch. Eventually they determined optimal values for all parameters. These optimal values allowed developing a design guide that leads to optimal arch design. When solving this problem, the authors used three-dimensional finite element models and the objective was to determine the most suitable solution for a road bridge, with a span of 100 meters, consisting of two inclined steel arches, located on a road with two traffic lanes, subjected to medium traffic. The virtual prototype of the model is performed by finite element simulator Midas Civil. Findings. In this study, for the bridge deck, a concrete tie appears to be the best solution considering the structural behavior of network arches, but economic advantages caused by easier erection may lead to steel or a composite bridge deck as better alternatives. Design requirements and local conditions of each particular bridge project will decide the most economic deck design.Originality. To ensure passenger comfort and the stability and continuity of the track, deformations of bridges are constricted. A network arch is a stiff structure with small deflections and therefore suitable to comply with such demands even for high speed railway traffic.
A network arch bridge with a concrete tie usually saves more than half the steel required for tied arches with vertical hangers and concrete ties. Practical value. Following the study design advice given in this article leads to savings of about 60 % of structural steel compared with conventional tied arch bridges with

  9. Land use patterns and landscape structures on the islands in Jeonnam Province’s Shinan County occasioned by the construction of mainland bridges

    Directory of Open Access Journals (Sweden)

    Jae-Eun Kim

    2016-06-01

    Full Text Available Land use in a specific region reflects the prevailing socioeconomic circumstances and cultures within that region. To this end, the current study analyzes the landscape structure of Shinan County using landscape indices based on land use to compare various socio-economic factors of the culture found on the islands of Shinan County. In addition, a cluster analysis was conducted to learn about the characteristics of islands exhibiting the same landscape structure. This analysis revealed that the landscape of the second largest island in Shinan County, Jido, was more fragmented than that of the biggest island Aphae. The cluster analysis led to the creation of three groups of islands exhibiting similar landscape structures. Group 1 is composed of the islands which are connected by a mainland bridge (called ‘yeonyukgyo’ in Korean. Group 2 and 3 also include the upper islands (those islands located in the northern area and lower islands (those islands located in the southern area in Shinan County. The presence of more advanced transportation systems and structures occasioned by their proximity to the island of Jido which was connected at an early date to the mainland ensured that the upper islands have historically been more frequently visited.

  10. Structural Loading of Cross Deck Connections for Trimaran Vessels

    National Research Council Canada - National Science Library

    Rhoads, Jason

    2004-01-01

    ...: longitudinal bending, transverse bending, torsional bending, spreading and squeezing of hulls, inner and outer hull slam pressures, wet deck slam pressures, loading from ship's motions, and whipping of slender hulls...

  11. Sumary of Tests and Studies Done Abroad on the Bubble Deck System

    Directory of Open Access Journals (Sweden)

    Sergiu Călin

    2009-01-01

    Full Text Available The procedure Bubble Deck was applied untill now in Europe, in countries like Austria, Belgium, Denmark, Germany, Iceland, Italy, United Kingdom, Holland, also in other continents, in Canada or USA. This constructive system could not be brought into practice in so many projects achieved, only based on fundamental research to prove its validity, therefore tests were made concerning: bending behavior, reaction to shear force, the behavior of mountings, the reaction to fire, the acoustic behavior of these floors and economic analysis.

  12. Mathematical bridges

    CERN Document Server

    Andreescu, Titu; Tetiva, Marian

    2017-01-01

    Building bridges between classical results and contemporary nonstandard problems, Mathematical Bridges embraces important topics in analysis and algebra from a problem-solving perspective. Blending old and new techniques, tactics and strategies used in solving challenging mathematical problems, readers will discover numerous genuine mathematical gems throughout that will heighten their appreciation of the inherent beauty of mathematics. Most of the problems are original to the authors and are intertwined in a well-motivated exposition driven by representative examples. The book is structured to assist the reader in formulating and proving conjectures, as well as devising solutions to important mathematical problems by making connections between various concepts and ideas from different areas of mathematics. Instructors and educators teaching problem-solving courses or organizing mathematics clubs, as well as motivated mathematics students from high school juniors to college seniors, will find Mathematical Bri...

  13. Finite Element Analysis of Concrete Bridge Slabs Reinforced with Fiber Reinforced Polymer Bars

    Directory of Open Access Journals (Sweden)

    S.E. El-Gamal

    2014-12-01

    Full Text Available Due to their non-corrosive nature, high strength and light weight, fiber reinforced polymers (FRP are being widely used as reinforcement in concrete bridges, especially those in harsh environments. The current design methods of concrete deck slabs in most bridge design codes assume a flexural behavior under traffic wheel loads. The load carrying capacities of concrete bridge deck slabs, however, are greatly enhanced due to the arching action effect developed by lateral restraints. This study presents the results of a non-linear finite element (FE investigation that predicts the performance of FRP reinforced concrete (RC deck slabs. The FE investigation is divided into two main parts: a calibration study and a parametric study. In the calibration study, the validity and accuracy of the FE model were verified against experimental test results of concrete slabs reinforced with glass and carbon FRP bars. In the parametric study, the effect of some key parameters influencing the performance of FRP-RC deck slabs bars was investigated. These parameters include the FRP reinforcement ratio, concrete compressive strength, slab thickness and span-to-depth ratio.

  14. Kings Covered Bridge rehabilitation, Somerset County, PA

    Science.gov (United States)

    William J. Collins; David C. Fischetti; Arnold M. Jr. Graton; Len Lichvar; Branden Diehl; James P. Wacker; Ed Cesa; Ed Stoltz; Emory L. Kemp; Samer H. Petro; Leon Buckwalter; John McNamara

    2005-01-01

    Kings Covered Bridge over Laurel Creek in Somerset County, Pennsylvania is approximately 114-foot clear span multiple Kingpost Truss with nail-laminated arches. This timber bridge is historically significant because it retains its original features of the 1860’s since the 1930s when it was spared from modernization by the construction of an adjacent steel highway...

  15. Bridges Over Troubled Waters: Theoretical Linguistics And ...

    African Journals Online (AJOL)

    This paper tries to construct a bridge between the concerns of theoretical linguistics and those of multilingualism and code-switching (CS) research. It argues that the primary special point of interaction between these fields lies in the question of potential equivalence between elements or categories, bridging across ...

  16. Standard plans for southern pine bridges

    Science.gov (United States)

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

    1995-01-01

    The development of standardized timber bridge plans and specifications is a key element in improving design and construction practices. The bridge plans presented were developed as a cooperative effort between the USDA Forest Service, Forest Products Laboratory (FPL); the University of Alabama; and the Southern Pine Council and are the first step in developing...

  17. Novel shear capacity testing of ASR damaged full scale concrete bridge

    DEFF Research Database (Denmark)

    Schmidt, Jacob Wittrup; Hansen, Søren Gustenhoff; Barbosa, Ricardo Antonio

    2014-01-01

    A large number of concrete bridges in Denmark have to undergo wide-ranging maintenance work to prevent deterioration due to aggressive Alkali Silica Reaction (ASR). This destructive mechanism results in extensive cracking which is believed to affect the load carrying capacity of the structure...... concrete bridges with considerable economical expenses as a consequence. A novel ASR test and measurement method, which can be used to perform shear testing locally on concrete bridges, is presented in this paper. Shear capacity testing is performed on a three span concrete bridge and several material test...... samples were taken from the test areas on the bridge deck. In addition, the test method is used to directly predict the shear capacity without disturbing the traffic significantly. Verification of the load carrying capacity of the bridge was the ultimate goal of the tests. A test rig, which could easily...

  18. Compressive membrane action in concrete decks

    NARCIS (Netherlands)

    Amir, S.

    2012-01-01

    One of the major challenges facing the designers today is to investigate if the old bridges are still safe for modern traffic. The current research deals with this question by taking into account compressive membrane action (CMA) in determining the capacity of reinforced and transversely prestressed

  19. Synthesis and pharmacology of novel analogues of oxytocin and deaminooxytocin: directed methods for the construction of disulfide and trisulfide bridges in peptides.

    Science.gov (United States)

    Chen, L; Zoulíková, I; Slaninová, J; Barany, G

    1997-03-14

    Using as models the neurohypophyseal nonapeptide hormone oxytocin and its analogue deaminooxytocin, several directed routes to formation of sulfur-sulfur bridges have been developed and evaluated. The linear sequences (through common octapeptide-resin intermediates) were assembled smoothly on tris(alkoxy)benzylamide (PAL) poly(ethylene glycol)-polystyrene (PEG-PS) graft supports, using stepwise Fmoc solid-phase chemistry. Side-chain protection of beta-mercaptopropionic acid (Mpa) and/or cysteine (Cys) was provided by S-2,4,6-trimethoxybenzyl (Tmob), S-acetamidomethyl (Acm), and/or a series of sulfenyl thiocarbonate and carbamoylsulfenyl protecting/activating groups: S-(methoxycarbonyl)sulfenyl (Scm), S-(methoxycarbonyl)disulfanyl (Sscm), S-(N-methyl-N-phenylcarbamoyl)sulfenyl (Snm), and S-(N-methyl-N-phenylcarbamoyl)disulfanyl (Ssnm). Thiolytic displacement of S-Snm (preferred) or S-Scm provided intramolecular cyclized peptide disulfides, and homologation of the chemistry with S-Ssnm (again preferred) and S-Sscm provided the corresponding trisulfides along with smaller amounts of disulfides and tetrasulfides. These chemistries could be implemented both in solution and in solid-phase modes. Various parameters were studied systematically and optimized, and the novel trisulfides of oxytocin and deaminooxytocin were synthesized and purified to homogeneity. The trisulfide compounds were evaluated in three assays: uterotonic in vitro, uterotonic in vivo, and pressor tests, and they showed substantial potencies, ranging from 5% to 40% of the parent (disulfide) activities, as well as protracted actions. The affinities of the peptide trisulfides to uterine membrane receptors were only 3.3-3.6-fold lower than those of the parent disulfides. Possible explanations of the biological results are discussed.

  20. 0-6652 : spliced Texas girder bridges.

    Science.gov (United States)

    2015-02-01

    Spliced girder technology continues to attract : attention due to its versatility over traditional : prestressed concrete highway bridge construction. : By joining multiple precast concrete girders using : post-tensioning, spliced girder technology :...