Artykuły w czasopismach: „Bridges, Concrete Testing”

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Phares, B. M., T. J. Wipf i F. W. Klaiber. "Laboratory Testing of Low-Volume Road Bridge Alternative". Transportation Research Record: Journal of the Transportation Research Board 1624, nr 1 (styczeń 1998): 148–59. http://dx.doi.org/10.3141/1624-18.

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In Iowa there are over 20,000 bridges on the secondary road system. The majority of these bridges are under the jurisdiction of county engineers with limited budgets; therefore many county engineers design and construct their own short-span bridges with their own labor force. The objective of this research is to perform laboratory testing on a bridge alternative that counties can design and construct. This concept involves the fabrication of precast units composed of two steel beams connected by a thin concrete deck. The concrete deck thickness is limited so that the units can be fabricated at one location and then transported to the bridge site. The number of units required is obviously a function of the width of bridge desired. After the precast units have been connected, an additional concrete deck is placed. The concrete surface of the units is scarified so that the two layers of concrete are bonded together, thus providing the required deck thickness. Since this bridge replacement system is primarily intended for use on low-volume roads, the precast units could be constructed with new or used steel beams. The laboratory testing program consisted of a series of small-scale tests on different types of precast deck connections, “handling strength” tests of the precast units, a series of tests on the model bridge with only the precast portion of the deck in place, and a series of tests on the fully constructed model bridge. For the bridge model tested [ L = 9750 mm (32 ft), W = 6400 mm (21 ft)], five precast connectors gave the desired lateral load distribution; the addition of the cast-in-place deck significantly improved the load distribution characteristics of the bridge system. The units developed and tested result in a simple-span bridge for low-volume roads that is relatively easy to construct.

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Zhang, Jin Quan, Hong Wei Ren i Bo Yu. "Failure Testing of a Full-Scale Reinforced Concrete T-Girder Bridge". Advanced Materials Research 243-249 (maj 2011): 1767–73. http://dx.doi.org/10.4028/www.scientific.net/amr.243-249.1767.

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As a common type of bridge, the reinforced concrete simply supported T-girder bridges have some usual disease problems such as web vertical cracks, incline cracks near the supports and diaphragm damage, and so on injured by transportation loads. In Shanxi province most of T-girder bridges appear to be under strength for current vehicle loads because most of which are designed by conventional methods and the old codes so it is important to evaluate how the existing damage influence the ultimate bearing capacity of the bridge. The destructive test is a directive mean of verifying the ultimate bearing capacity of bridges. This paper provides details of a destructive load test of a T-girder bridge called Zuojiabao Bridge. It describes the analysis performed prior to testing, aimed at predicting the response of the structure at both serviceability and ultimate states, and discusses the results obtained.The development rule of strain, deflection and crack and the ultimate bearing capacity of the bridge were obtained through the destructive test process. The results showthat although the old T-girder bridge has enough bearing capacity to satisfy the new vehicle standard, it is strongly recommended to strengthen or retrofit the bridge. And the finite element analysis can be effectively applied to the failure analysis of the reinforced concrete T-girder bridge subjected to destructive load.

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Knickerbocker, David J., Prodyot K. Basu, Mark A. Holloran i Edward P. Wasserman. "Recent Experience with High-Performance Concrete Jointless Bridges in Tennessee". Transportation Research Record: Journal of the Transportation Research Board 1845, nr 1 (styczeń 2003): 104–14. http://dx.doi.org/10.3141/1845-12.

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Experimental and analytical studies of two high-performance concrete (HPC) jointless bridges with integral abutments built in Tennessee as part of the FHWA’s nationwide initiative to implement HPC in bridge structures are presented. Performance of the two bridges is observed through all stages of construction and service to date, via material testing, bridge instrumentation for both short- and long-term performance monitoring, and live-load testing. The up-to-date observed performance of the bridges reveals the success of such bridge construction. Local contractors were found to be capable of producing concrete to meet increased requirements in strength and durability parameters. In addition, new insights were derived about HPC behavior in such applications, identifying the areas requiring updating of current practice. Load test data revealed that load distribution among the girders is in marked difference from codes of practice. Thermal response of the bridges indicated longitudinal flexibility offered by the jointless construction.

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Aguilar, Carlos V., David V. Jáuregui, Craig M. Newtson, Brad D. Weldon i Tamara M. Cortez. "Load Rating a Prestressed Concrete Double T-Beam Bridge without Plans by Field Testing". Transportation Research Record: Journal of the Transportation Research Board 2522, nr 1 (styczeń 2015): 90–99. http://dx.doi.org/10.3141/2522-09.

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Bridges with no design plans are an issue in New Mexico because of the many that exist throughout the state. Conventional load rating techniques cannot be used because these bridges have limited or no design documentation. This lack of information has created uncertainties regarding the load-carrying capacity of these structures. Only a few states have formal procedures on how these particular bridges should be load rated. A project was conducted for the New Mexico Department of Transportation to develop a procedure for load rating bridges without plans, including prestressed concrete bridges. In accordance with the AASHTO Manual for Bridge Evaluation, a prestressed concrete double T-beam bridge was evaluated with advanced analyses and experimental methods (including load testing and nondestructive material evaluation techniques). A four-step load rating procedure was implemented that included estimating the prestressing steel by Magnel diagrams, verifying the estimate with a rebar scanner, testing the bridge at both diagnostic and proof loads based on strain measurements, and using the proof test results to rate the bridge. Rating factors and posting loads were determined for AASHTO and New Mexico legal loads. Because of the poor condition of the shear keys (some of which were broken), it is shown that the load distribution between beams was adversely affected and the bridge should be load posted.

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Benmokrane, Brahim, Ehab El-Salakawy, Amr El-Ragaby i Sherif El-Gamal. "Performance evaluation of innovative concrete bridge deck slabs reinforced with fibre-reinforced-polymer bars". Canadian Journal of Civil Engineering 34, nr 3 (1.03.2007): 298–310. http://dx.doi.org/10.1139/l06-173.

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This paper presents the construction details, field testing, and analytical results of six innovative concrete bridges reinforced with fibre-reinforced-polymer (FRP) bars recently constructed in North America, namely Wotton, Magog, Cookshire-Eaton, Val-Alain, and Melbourne bridges in Quebec, Canada, and Morristown bridge in Vermont, USA. All six bridges are girder type, with main girders made of either steel or prestressed concrete. The main girders are supported over spans ranging from 26.2 to 50.0 m. The deck is a 200–230 mm thick concrete slab continuous over spans of 2.30–3.15 m. Different types of glass- and carbon-FRP reinforcing bars and conventional steel were used as reinforcement for the concrete deck slab. The six bridges are located on different highway categories, which means different traffic volume and environmental conditions. The bridges are well instrumented at critical locations for internal temperature and strain data collection using fibre optic sensors. These sensors are used to monitor the deck behaviour from the time of construction to several years after the completion of construction. The bridges were tested for service performance using calibrated truckloads. In parallel, a finite element analysis (FEA) was conducted and verified against the results of the field load tests. The FEA was then used to run parametric studies to investigate the effect of several important parameters such as FRP reinforcement type and ratio on the service and ultimate behaviour of these bridge decks. The analytical and field results under real service conditions, in terms of deflections, cracking, and strains in reinforcement and concrete, were comparable to those of concrete bridge deck slabs reinforced with steel.Key words: bridges deck slabs, fibre-reinforced-polymer (FRP) bars, field testing, finite element analysis.

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Buckle, I. G., A. R. Dickson i M. H. Phillips. "Ultimate strength of three reinforced concrete highway bridges". Canadian Journal of Civil Engineering 12, nr 1 (1.03.1985): 63–72. http://dx.doi.org/10.1139/l85-007.

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The destructive testing of three reinforced concrete highway bridges, recently made redundant by road realignment, is summarized. The procedure used to test the bridges to ultimate conditions is described and load capacities of about 20 times class 1 axle loads are reported for all structures. Analyses based on conventional ultimate strength theory can account for only two-thirds of these ultimate loads and then only if second order effects are included. A nonlinear finite element computer program has been developed and used to analyze one of these structures. Excellent prediction of the ultimate load is made by the program. It is therefore suggested that compressive membrane action, which is automatically modelled in the finite element solution, plays a significant role in the enhancement of load capacity.The paper concludes that a more sophisticated approach to the assessment of bridge load capacity is necessary if realistic estimates of actual strength are to be made. Limited experience with a nonlinear finite element program suggests one such approach. If used with care, some relief to the bridge replacement program can be expected. Key words: highway bridges, ultimate load capacity, finite element analysis, reinforced concrete, field testing, compressive membrane action.

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Yan, Wei Ming, Yong Li i Yan Jiang Chen. "Seismic Testing of a Long-Span Concrete Filled Steel Tubular Arch Bridge". Key Engineering Materials 456 (grudzień 2010): 89–102. http://dx.doi.org/10.4028/www.scientific.net/kem.456.89.

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Long-span bridges are always a multi-support structural system, and seismic ground motion can vary significantly over distances comparable to the length of such kind of bridges, so it’s difficult to carry out shaking table tests because of the restriction of the dimension and amount of shaking tables. This paper discusses the multiple sub-table cordwood system is used to conduct a study on the seismic testing of a three-span irregular Concrete filled steel tubular (CFST) arch bridge with the objective of investigating the dynamic performance of the bridge under spatial earthquake motions. The development and testing of the bridge model and selected experimental results are discussed then. The seismic response and response characteristics of acceleration, displacement, internal force, and strain of the structure under earthquake excitations are gained, which can provide test data and basis to evaluate the seismic performance of this CFST arch bridge or other similar structural system design.

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Jin, B., D. Liu i CK Zhu. "Experimental study on bridge vibration test". Journal of Physics: Conference Series 2158, nr 1 (1.01.2022): 012016. http://dx.doi.org/10.1088/1742-6596/2158/1/012016.

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Abstract Taking Chaihe bridge in Tieling City and Songhuajiang railway bridge on Binbei line as examples, the vibration test is carried out by using the environmental excitation method. By testing and comparing the first three typical vibration modes of the two bridges, and the experimental research shows that: A. compared with Concrete-Filled Steel Tubular Bridge, truss bridge has higher stiffness. B. The span and height of truss bridge can be higher and farther than that of Concrete-Filled Steel Tubular Bridge; C. Truss bridge is more convenient in testing, maintenance and health monitoring, and has good performance and stability.

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Ghindea, Cristian Lucian, Ionut Radu Racanel i Radu Cruciat. "Dynamic Testing of a Reinforced Concrete Road Bridge". Key Engineering Materials 601 (marzec 2014): 207–10. http://dx.doi.org/10.4028/www.scientific.net/kem.601.207.

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Considering on one hand the calculation model of the bridge, simplifying assumptions and design criteria and on the other hand the inherent differences between the project and final structure, the real structure behaviour under traffic loads can be different from that one considered in the design stage. Therefore the need of experimental tests before commissioning of bridges arises and this task is generally conditioned by complexity of the structure, the technologies used in construction and the requirements of the relevant stakeholders. The paper presents the test conditions for a reinforced concrete road bridge in Romania and the results obtained following the experimental tests. The experimentally determined dynamic characteristics of the bridge and the peek vertical accelerations are compared with those obtained by performing numerical analyses of the bridge. Due to the fact that the bridge is provided with walkways, it is appropriate to presume that the vibrations induced by road traffic will affect the pedestrians walking on the bridge. Same experimental data presented above can provide a view into how traffic induced vibrations can affect pedestrians on the bridge. For this reason, in the paper are presented the results in terms of human perception and the comparison between the resulting values and some generally accepted values

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Zoubir, Hajar, Mustapha Rguig i Mohammed Elaroussi. "Crack recognition automation in concrete bridges using Deep Convolutional Neural Networks". MATEC Web of Conferences 349 (2021): 03014. http://dx.doi.org/10.1051/matecconf/202134903014.

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Using Unmanned Aerial Systems (UASs) for bridge visual inspection automation necessitates the implementation of Deep Convolutional Neural Networks (DCNNs) to process efficiently the large amount of data collected by the UASs sensors. However, these networks require massive training datasets for the defects recognition and detection tasks. In an effort to expand existing concrete defects datasets, particularly concrete cracks in bridges, this paper proposes a public benchmark annotated image dataset containing over 6900 images of cracked and non cracked concrete bridges and culverts. The presented dataset includes some challenging surface conditions and covers concrete cracks with different sizes and patterns. The authors analyzed the proposed dataset using three state of the art DCNNs in Transfer Learning mode. The three models were used to classify the cracked and non cracked images and the best testing accuracy obtained reached 95.89%. The experimental results showcase the potential use of this dataset to train deep networks for concrete crack recognition in bridges. The dataset is publicly available at https://github.com/MCBDD-ZRE/Concrete-Bridge-Crack-Dataset- for academic purposes.

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Al-Mahaidi, Riadh, Geoff Taplin i Armando Giufre. "Load Distribution and Shear Strength Evaluation of an Old Concrete T-Beam Bridge". Transportation Research Record: Journal of the Transportation Research Board 1696, nr 1 (styczeń 2000): 52–62. http://dx.doi.org/10.3141/1696-08.

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There are about 330 T-beam bridges in the Australian state of Victoria that were built before 1950. Australia-wide there are nearly 1,000 of these early T-beam bridges. The shear capacity of these bridges, when assessed in accordance with current codes of practice, is in some cases not adequate for the current design loading. In 1996, VicRoads, the Victorian state road authority, initiated a project to enable a more accurate assessment of the shear capacity of these bridges to be made so that decisions on load rating or replacement could be made. An analysis of an existing reinforced concrete T-beam bridge that had been identified for a load test to failure was commissioned. The purpose of the analysis was to predict the load distribution behavior and the ultimate strength and to advise on the testing and monitoring program. After successful load testing of the bridge, a comprehensive analysis of the observed behavior was carried out and compared with the theoretical models. The pre-and posttesting analysis, which was undertaken with linear and nonlinear finite element analysis and with the modified compression field theory, are described and the analysis results are compared with the real behavior of the tested bridge. In particular, the load distribution in the elastic range and the ultimate shear strength of the reinforced concrete T-beams are discussed. The consequences of these findings on the load rating procedures are discussed, and a strategy for rating old reinforced concrete T-beam bridges is outlined.

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Russo, Francesco M., Terry J. Wipf i F. Wayne Klaiber. "Diagnostic Load Tests of a Prestressed Concrete Bridge Damaged by Overheight Vehicle Impact". Transportation Research Record: Journal of the Transportation Research Board 1696, nr 1 (styczeń 2000): 103–10. http://dx.doi.org/10.3141/1696-50.

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A series of diagnostic load tests performed on two prestressed concrete bridges located in western Iowa are discussed. The bridges are dual prestressed concrete I-beam structures. In June 1996, an overheight vehicle struck the westbound structure and caused significant loss of section and cracking. As a result of the severity of the damage and because of concerns about the remaining capacity and long-term durability of the damaged beams, the Iowa Department of Transportation decided to remove the two most severely damaged beams. The diagnostic load-testing portion of the research program consisted of positioning test vehicles of known weight at predetermined locations along the deck of the damaged westbound and undamaged eastbound bridge. Single-and dual-truck tests were conducted on each bridge. Following replacement of the damaged beams in the westbound structure, additional tests were conducted. The results of these three load tests are compared to determine the effect of the localized beam damage on the overall live load distribution pattern in the bridge. The objective of this research is to determine the effects of damage on the load distribution and the remaining strength of damaged prestressed concrete bridges. Noticeable differences in response were detected in the westbound and eastbound bridges before beam replacement, with the difference essentially disappearing after the repair of the westbound bridge. The research project also involved model bridge testing, along with the repair of the beams that were removed from service and those that were intentionally damaged in the laboratory. The project is now complete.

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Alkhrdaji, Tarek, Antonio Nanni i Randy Mayo. "Upgrading Missouri Transportation Infrastructure: Solid Reinforced-Concrete Decks Strengthened with Fiber-Reinforced Polymer Systems". Transportation Research Record: Journal of the Transportation Research Board 1740, nr 1 (styczeń 2000): 157–63. http://dx.doi.org/10.3141/1740-20.

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More than 40 percent of the bridges in the United States need repair, strengthening, or replacement. Because of limited funds, many states are forced to post load restrictions on their bridges as a temporary measure. Recently, fiber-reinforced polymers (FRPs) have emerged as a practical solution for repair or strengthening of highway bridges. Since there are no nationally accepted specifications for design and construction with bonded FRP reinforcement, the Missouri Department of Transportation (MoDOT) has funded a research program aimed at validating the design and analysis procedure through strengthening and testing to failure of bridges under realistic highway loading and conditions. Two bridges, Bridge G270 and Bridge J857, were selected for this demonstration. Both bridges are solid reinforced-concrete (RC) slab bridges. Bridge G270 was strengthened to increase its load-carrying capacity by using externally bonded carbon FRP and is still in service. Two of the three deck slabs of Bridge J857 were strengthened with FRP composites. Elastic tests were conducted on Bridge G270 before and after strengthening. Laboratory and field tests were conducted to validate the analytical model and design capacity. The decks of Bridge J857 were tested to failure under static loads. Test results indicate that strengthening with FRP can increase the capacity of solid-slab bridge decks. Strength and failure modes can be predicted by using the classical approach for RC design and analysis, based on equilibrium and compatibility. The research program, strengthening techniques, test results, and modes of failure of the bridge decks tested are reported.

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Zhang, Li Hai, Maizuar Maizuar, Priyan Mendis, Colin Duffield i Russell Thompson. "Monitoring the Dynamic Behaviour of Concrete Bridges Using Non-Contact Sensors (IBIS-S)". Applied Mechanics and Materials 846 (lipiec 2016): 225–30. http://dx.doi.org/10.4028/www.scientific.net/amm.846.225.

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The maintenance and operation of bridges represent a significant investment in both the public and private domains. In practice, the structural damage of a bridge that accumulates over its life-span is a result of continuous degradation caused mainly by traffic conditions and sudden extreme events (e.g. flooding, fires and severe traffic accidents). However, under heavy truck loading, the deterioration rate of a bridge can be accelerated. As the use of heavier articulated trucks becomes increasingly popular in contemporary freight transportation systems, the development of modern Non-Destructive Testing (NDT) techniques in conjunction with computational modelling becomes necessary. The advancement in this area will allow rapid assessment of the structural health of bridges and detection of ongoing damage to enhance the structural performance of bridges.

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Miller, R., B. Shahrooz, T. M. Baseheart, E. Long, J. Jones, R. Knarr i R. Sprague. "Testing of High-Performance Concrete Single-Span Box Girder". Transportation Research Record: Journal of the Transportation Research Board 1624, nr 1 (styczeń 1998): 118–24. http://dx.doi.org/10.3141/1624-14.

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As part of a multistate research program on use of high-performance concrete (HPC) in highway bridges, a bridge originally designed as a three-span adjacent box girder bridge was converted to a single-span bridge by using 70-MPa HPC and 15-mm strands. As part of the research, a test beam was constructed and tested. Instruments placed in the beam before casting were used to measure transfer length, which was found to be approximately 1.22 m, larger than the 50-bar diameters usually used in the American Association of State Highway and Transportation Officials (AASHTO) Standard Specifications but consistent with recent studies. After the beam concrete reached the required compressive strength, it was tested to destruction. The beam was able to resist the required AASHTO ultimate moment without failure. It was found that the AASHTO cracking load was conservative for this beam, mostly because the measured modulus of rupture greatly exceeded the value assumed in the AASHTO specifications. The behavior of the beam was successfully predicted using a section analysis.

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Das, P. C., J. S. Owen, B. J. Eccles, M. A. Woodings i B. S. Choo. "Role of Dynamic Testing in Assessment of Bridges". Transportation Research Record: Journal of the Transportation Research Board 1594, nr 1 (styczeń 1997): 115–24. http://dx.doi.org/10.3141/1594-12.

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Six reinforced concrete beams were loaded incrementally up to failure. After each increment the load was removed and measurements of the modal properties of the beams were made by impulse testing. The variation of the natural frequencies, frequency ratios, mode shapes, and the level of damage were investigated. It was found that on completion of the tests the natural frequencies of the beams had been reduced by an average of 25 percent in each mode. However, changes in mode shape were very small, and appreciable differences were only observed when the damage was highly localized. Modeling of the beam by using finite elements predicted trends that compared well with experimental observations. It is concluded that if dynamic testing were used in monitoring reinforced concrete structures, then the changes in frequency due to initial concrete cracking or yield of the reinforcement could be detected. More useful information associated with the spread and type of cracking through a structure may be detectable, although the level of the frequency changes is of the same order as those due to changes in ambient conditions.

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Hillebrand, Matthias, i Josef Hegger. "Fatigue Testing of Shear Reinforcement in Prestressed Concrete T-Beams of Bridges". Applied Sciences 10, nr 16 (11.08.2020): 5560. http://dx.doi.org/10.3390/app10165560.

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In the recent years, bridges, as an important part of the national and international infrastructure, had to comply with stricter requirements due to increased heavy load traffic. Many of these bridge structures built in the 1960s and 1970s often contain less web reinforcement than the modern required minimum web reinforcement. In this context, the shear resistance under cyclic loading is of special interest. For this reason, experimental tests were conducted on prestressed concrete beams with and without shear reinforcement at the Institute of Structural Concrete of RWTH Aachen University to investigate the shear fatigue strength. This paper describes the recent tests on ten Tshaped prestressed beams with web reinforcement. The specimens were able to resist more load cycles than predicted by the approaches implemented in the Eurocodes for bridges. Based on the test results, design models for shear under cyclic loading should be reviewed and improved, especially regarding the assessment of existing structures.

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Zhao, Fu Li, Yi Qiang Xiang i Qiang Qiang Wu. "Research on Monitoring and Control for Suspender Cable Tension of Half-Through Concrete Filled Steel Tube Arch Bridge". Advanced Materials Research 859 (grudzień 2013): 131–34. http://dx.doi.org/10.4028/www.scientific.net/amr.859.131.

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The measurement accuracy of the cable tensions in the hanger rods of concrete filled steel tube arch bridges is important for the correct evaluation of bridges condition. Based on Jinpan Bridge-a half through concrete filled steel tube arch bridge with 80 m span in Tiantai, it was put forward the vibration frequency method for testing and evaluate suspender tensions with the help of analysis vibration characters of the suspender. The precision of cable force calculation formula was verified after comparing the practical tension with the designed tension obtained from tension jack method. Then, according to the test results and values predicted by the presented cable force calculation formula, the cable tensions were adjusted. Cable tension test results in the finished bridge show that this method is feasible.

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Li, Yan, Xiaolong Ma i Wei Zhang. "Dynamic performance of a concrete-filled steel tube high-pier curved continuous truss girder bridge due to moving vehicles". Advances in Structural Engineering 22, nr 6 (23.11.2018): 1297–311. http://dx.doi.org/10.1177/1369433218811539.

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The dynamic performance of a new type of concrete-filled steel tube high-pier curved continuous truss girder bridges under moving vehicles is studied combining field testing and numerical simulation method by an actual bridge example. The dynamic response data were obtained before opening to traffic for the bridge under moving testing vehicles. A three-dimensional vehicle and bridge coupled vibration analysis model for curved bridges is proposed and validated. The dynamic behavior characteristics and vehicular ride comfort for this new type bridge are studied considering variable road surface and other conditions. The results indicate that the dynamic impacts of this bridge from vehicles are underestimated compared with those defined in the design code. In addition, the dynamic impact factors vary significantly for the local components and some of them could exceed the design value. Finally, the riding comfort of this bridge is evaluated, which suggests a fairly uncomfortable condition.

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Tajalli, S. M. A., i S. R. Rigden. "Partially and non-destructive testing of 40 concrete bridges". Proceedings of the Institution of Civil Engineers - Structures and Buildings 140, nr 1 (luty 2000): 25–38. http://dx.doi.org/10.1680/stbu.2000.140.1.25.

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Wipf, Terry J., F. Wayne Klaiber, J. Scott Ingersoll i Douglas L. Wood. "Field and Laboratory Testing of Precast Concrete Channel Bridges". Transportation Research Record: Journal of the Transportation Research Board 1976, nr 1 (styczeń 2006): 88–94. http://dx.doi.org/10.1177/0361198106197600110.

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Wahab, M. M. Abdel, i G. De Roeck. "Dynamic Testing of Prestressed Concrete Bridges and Numerical Verification". Journal of Bridge Engineering 3, nr 4 (listopad 1998): 159–69. http://dx.doi.org/10.1061/(asce)1084-0702(1998)3:4(159).

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Leng, Yanling, Jinquan Zhang, Ruinian Jiang i Yangjian Xiao. "Structural Redundancy Assessment of Adjacent Precast Concrete Box-Beam Bridges in Service". Advances in Materials Science and Engineering 2020 (15.02.2020): 1–10. http://dx.doi.org/10.1155/2020/5801841.

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Present approaches for assessing bridge redundancy are mainly based on nonlinear finite element (FE) analysis. Unfortunately, the real behavior of bridges in the nonlinear range is difficult to evaluate and a sound basis for the nonlinear FE analysis is not available. In addition, a nonlinear FE analysis is not feasible for practitioners to use. To tackle this problem, a new simplified approach based on linear FE analysis and field load testing is introduced in this paper to address the particular structural feature and topology of adjacent precast concrete box-beam bridges for the assessment of structural redundancy. The approach was first experimentally analyzed on a model bridge and then validated by a case study. The approach agrees well with the existing recognized method while reducing the computation complexity and improving the reliability. The analysis reveals that the level of redundancy of the bridge in the case study does not meet the recommended standard, indicating that the system factor recommended by the current bridge evaluation code for this bridge is inappropriate if considering the field condition. Further research on the redundancy level of this type of bridges is consequently recommended.

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Cho, Doo Yong, Sun Kyu Park i Woo Seok Kim. "Live Load Distribution in Prestressed Concrete Girder Bridges with Curved Slab". Applied Mechanics and Materials 284-287 (styczeń 2013): 1441–45. http://dx.doi.org/10.4028/www.scientific.net/amm.284-287.1441.

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This paper presents the live load distribution in straight prestressed concrete (PSC) girder bridges with curved deck slab utilizing finite element analyses. Numerical modeling methodology was established and calibrated based on field testing results. A parametric study of 73 cases with varying 6 critical parameters was used to determine a trend over each parameter. Through live load girder distribution factor (GDF) comparisons between the AASHTO LRFD, AASHTO Standard factors and finite element analyses results, both AASHTO live load distribution predicted conservatively in most bridges considered in the parametric study. However, in the bridges with curved slab, GDF was underestimated due to curvature influences. This study proposes a new live load distribution formula to predict rational and conservative live load distribution in PSC girder bridges with curved slab for a preliminary design purpose. The proposed live load distribution provides better live load analysis for the PSC girder bridge with curved slab and ensures the GDF is not underestimated.

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Andersson, Louise, Johan Silfwerbrand, Anders Selander i Jan Trägårdh. "Effect of High-Pressure Washing on Chloride Ingress in Concrete – Development of an Accelerated Test Method". Nordic Concrete Research 67, nr 2 (1.12.2022): 35–50. http://dx.doi.org/10.2478/ncr-2022-0013.

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Abstract Bridges constitute an important part of the infrastructure. For bridges to have the longest possible service life with minimum repairs, the maintenance is of great importance. One type of bridge maintenance that is rarely researched is the continuous preventive maintenance. The continuous preventive maintenance consists of removal of vegetation, cleaning of bridge joints and drainage systems as well as high-pressure washing of the structure. The effect of washing is discussed but not properly researched. A study on the effectiveness of high-pressure washing on concrete is therefore being conducted. An accelerated test method is being developed to mimic field testing. The method has been developed through tests on small concrete specimens subjected to fluctuating temperature, fluctuating moisture, and repeatable exposure to de-icing salt during several cycles. The specimens are of two recipes where one represents an old concrete bridge with rather high water-cement ratio (0.6) and the other one represents a new concrete bridge with a low water-cement ratio (0.4). The first two versions of the method are described. The second version shows promising results, but the method needs further development to incorporate additional factors.

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Sainz-Aja, Jose, Carlos Thomas, Juan A. Polanco i Isidro Carrascal. "High-Frequency Fatigue Testing of Recycled Aggregate Concrete". Applied Sciences 10, nr 1 (18.12.2019): 10. http://dx.doi.org/10.3390/app10010010.

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Concrete fatigue behaviour has not been extensively studied, in part because of the difficulty and cost. Some concrete elements subjected to this type of load include the railway superstructure of sleepers or slab track, bridges for both road and rail traffic and the foundations of wind turbine towers or offshore structures. In order to address fatigue problems, a methodology was proposed that reduces the lengthy testing time and high cost by increasing the test frequency up to the resonance frequency of the set formed by the specimen and the test machine. After comparing this test method with conventional frequency tests, it was found that tests performed at a high frequency (90 ± 5 Hz) were more conservative than those performed at a moderate frequency (10 Hz); this effect was magnified in those concretes with recycled aggregates coming from crushed concrete (RC-S). In addition, it was found that the resonance frequency of the specimen–test machine set was a parameter capable of identifying whether the specimen was close to failure.

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Patil, Mayur V., i Dr S. R. Parekar. "Nonlinear Analysis of External Post-Tensioning anchorage of Concrete Segment". International Journal for Research in Applied Science and Engineering Technology 11, nr 1 (31.01.2023): 1010–20. http://dx.doi.org/10.22214/ijraset.2023.48754.

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Abstract: Precast concrete segmental bridges (PCSBs) have been the most common design technology used in the last decades. In these studies Non-linear structural performances of externally prestressed, precast concrete segmental bridges (PCSB). PCSBs with externally prestressed tendons have become very popular in construction because of economical and safety reasons, fast and practical construction, and outstanding serviceability. External tendons technique is widely used because it allows to inspect the cables and to replace them or to reinforce the tendons in case of damage while such kinds of actions are difficult to be taken in case of internal prestressing. It is widely recognized that segmental bridges have better durability, lower life-cycle costs and higher quality for maintenance than other types of bridges. However, there is lack of reliable computational model for analyzing behavior of post-tensioned PCSBs. Experimental analysis of bridge segment required more cost, time and effort for the analysis and also take cake of quality of material, cast process, curing, and testing. This research presents the results of stress and strain state of the local bearing area caused by a Prestressed cable anchor in reinforced concrete bridge segment. Nonlinear analysis of anchorage and rebar, concrete segment can be carried out by analytical solution calculated with the reference of ACI 318/19. ANSYS software is used for model and analyze the structure. The analysis process was carried out in 3 types : linear elastic analysis, nonlinear elastic analysis, and nonlinear analysis considering the destruction of concrete, and the value is compared with ANSYS software ( static structure).

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Bakht, Baidar, i Akhilesh C. Agarwal. "Deck slabs of skew girder bridges". Canadian Journal of Civil Engineering 22, nr 3 (1.06.1995): 514–23. http://dx.doi.org/10.1139/l95-060.

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Canadian codes allow the design of concrete deck slabs of slab-on-girder bridges by taking account of the internal arching action that develops in these slabs under concentrated wheel loads in particular. Provided that certain prescribed conditions are met, a deck slab is deemed to have met the design criteria if it is provided with a top and a bottom layer of steel reinforcement with each layer consisting of an orthogonal mesh of steel bars in which the area of cross section of the bars in each direction is at least 0.3% of the effective area of cross section of the deck slab. For deck slabs of bridges having skew angles greater than 20°, the codes require the minimum amount of reinforcement to be doubled in the end zones near the skew supports. Model testing has shown that need for such an increase can be eliminated by providing composite end diaphragms with high flexural rigidity in the horizontal plane. The proposed concept is tested on a model of fibre-reinforced concrete deck without steel reinforcement in which deficiencies in the confinement of the deck slab readily manifest themselves in form of a bending, rather than punching shear, failure. Key words: highway bridges, bridge decks, deck slabs, skew deck, skew bridges, fibre-reinforced concrete decks.

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Sun, Hang, Da Peng Chen i Ying Ping Wu. "Evaluation and Study on the Bearing Capacity of Deck Type Concrete Arch Bridge". Key Engineering Materials 648 (czerwiec 2015): 72–79. http://dx.doi.org/10.4028/www.scientific.net/kem.648.72.

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As more and more arch bridges built with the construction method of cantilever erection, the strength and entirety of the bridge shall worry the designers. This paper studies an arch bridge with a 65-meter span, gives the static loading test plan and the dynamic test plan, analyzes the testing data of the displacement and strain, explains the methods of static and dynamic load test in detail, and gives a conclusion about the bearing capacity and dynamic properties of bridge. This can be referred by the similar bridge.

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Omar, Tarek, i Moncef Nehdi. "Condition Assessment of Reinforced Concrete Bridges: Current Practice and Research Challenges". Infrastructures 3, nr 3 (14.09.2018): 36. http://dx.doi.org/10.3390/infrastructures3030036.

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One quarter of bridges in Canada and the United States need repair. The present study provides a critical overview of the state-of-the-art existing condition assessment techniques for reinforced concrete bridges, with an emphasis on current practice in North America. The techniques were classified into five categories, including visual inspection, load testing, non-destructive evaluation, structural health monitoring, and finite element modelling. The potential applications of these technologies are discussed and compared, highlighting their primary advantages and limitations. The review revealed that quantitative assessment could be effectively achieved using several complementary technologies. It is shown that there is need for concerted research efforts to achieve automated data collection and interpretation analyses. Also, the configuration of monitoring systems was found to be paramount in effectively assessing bridge performance parameters of interest. The study suggests appropriate investigation methods for some bridge deterioration mechanisms. Knowledge gaps and challenges in this field are outlined in order to motivate further research and development of these technologies.

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Doran, D. "Discussion: Partially and non-destructive testing of 40 concrete bridges". Proceedings of the Institution of Civil Engineers - Structures and Buildings 152, nr 1 (luty 2002): 90. http://dx.doi.org/10.1680/stbu.2002.152.1.90.

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Tajalli, S. M. A., S. R. Rigden i D. Doran. "Discussion: Partially and non-destructive testing of 40 concrete bridges". Proceedings of the Institution of Civil Engineers - Structures and Buildings 152, nr 3 (sierpień 2002): 295. http://dx.doi.org/10.1680/stbu.2002.152.3.295.

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Lantsoght, Eva O. L., Cor van der Veen, Ane de Boer i Dick A. Hordijk. "State-of-the-art on load testing of concrete bridges". Engineering Structures 150 (listopad 2017): 231–41. http://dx.doi.org/10.1016/j.engstruct.2017.07.050.

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Innocenzi, Raoul Davide, Vanni Nicoletti, Davide Arezzo, Sandro Carbonari, Fabrizio Gara i Luigino Dezi. "A Good Practice for the Proof Testing of Cable-Stayed Bridges". Applied Sciences 12, nr 7 (31.03.2022): 3547. http://dx.doi.org/10.3390/app12073547.

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This paper presents the results and interpretations of static and dynamic tests that were executed on a newly built cable-stayed steel-concrete composite bridge during the final proof testing. A brief description of the structure, the testing methodology, and the used instrumentation are presented. Then, the test results are widely discussed and interpreted in order to evaluate the bridge performance during the proof test and also to understand the usefulness of each performed test in a proof test framework. All the collected experimental data are also compared to the numerical ones that were obtained through a refined finite element model, in order to check the behavior of the structure. The outcomes of the present work can offer references for the proof testing and monitoring of cable-stayed bridges.

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35

N.S. Ngo, T. Pape, R.P. Kotze i R.W. Pritchard. "Load Testing and In-service Monitoring of Transversely Stressed Deck Unit Bridges". Electronic Journal of Structural Engineering 14, nr 1 (1.01.2015): 85–96. http://dx.doi.org/10.56748/ejse.141911.

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Transversely stressed precast concrete deck unit bridges are a common type of small and medium span bridge on the Queensland road network. This type of bridge is unique in design featuring transverse posttensioned stressing bars with a low level of prestressing, stiff upright kerb units and no shear keys. Recent structural assessments of these bridge types has yielded varied and at times inconsistent results, with theoretical structural deficiencies identified at odds with the lack of evidence of structural distress, demonstrating acceptable performance. A test program was developed to address this disparity and improve understanding of the structural performance of these bridge types. This included static and dynamic load testing with various vehicle types, and long-term monitoring of the behaviour of a representative bridge under ambient traffic. The test results have enabled improved understanding of the behaviour and true capacity of this bridge type, as well as providing inputs to enable validation of analytical structural modelling techniques.

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Savino, Pierclaudio, Francesco Tondolo, Donato Sabia, Antonino Quattrone, Fabio Biondini, Gianpaolo Rosati, Mattia Anghileri i Bernardino Chiaia. "Large-Scale Experimental Static Testing on 50-Year-Old Prestressed Concrete Bridge Girders". Applied Sciences 13, nr 2 (7.01.2023): 834. http://dx.doi.org/10.3390/app13020834.

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The heritage of existing road infrastructures and in particular of bridges consists of structures that are approaching or exceeding their designed service life. Detrimental causes such as aging, fatigue and deterioration processes other than variation in loading conditions introduce uncertainties that make structural assessment a challenging task. Experimental data on their performances are crucial for a proper calibration of numerical models able to predict their behavior and life-cycle structural performance. In this scenario, an experimental research program was established with the aim of investigating a set of 50-year-old prestressed concrete bridge girders that were recovered from a decommissioned bridge. The activities included initial non-destructive tests, and then full-scale load tests followed by a destructive test on the material samples. This paper reports the experimental results of the full-scale tests conducted on the first group of four I-beams assumed to be in good condition from visual inspection at the time of testing. Loading tests were performed using a specifically designed steel reaction frame and a test setup equipment, as detailed in the present work. Due to the structural response of this first group of girders, a uniform behavior was found at both service and ultimate conditions. The failure mechanism was characterized by the crushing of the cast-in-situ top slab corresponding to a limited deflection, highlighting a non-ductile behavior. The outcomes of the experimental research are expected to provide new data for the life-cycle safety assessment of existing bridges through an extended database of validated experimental tests and models.

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Hu, Chun Hua, Qiao Zhu, Xiao Zhou Ma i Fang Yu. "Preliminary Investigation of Influence of Special Testing on Bridge Structure Durability". Advanced Materials Research 1065-1069 (grudzień 2014): 889–93. http://dx.doi.org/10.4028/www.scientific.net/amr.1065-1069.889.

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Based on bridges routine examination, special detection is in-depth and meticulous testing that according to the disease characteristics, using some expertise technology and testing equipment for steel corrosion, concrete carbonization, the thickness of the protective layer and component quality to some key parts or typical bridge opening. Bridge condition of technology can be controlled more fully and accurately through a special bridge inspection, combined with conventional test results on the status of a comprehensive assessment of structures. This may provide technical data for the next bridge inspection count and load test, moreover, according to the variation of the data in the field test, it may dedicate variation characteristic and influencing factors for damage of structural durability from these special detections.

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CAI, C. S., M. ARAUJO, A. NAIR i X. SHI. "STATIC AND DYNAMIC PERFORMANCE EVALUATION OF A PRE-STRESSED CONCRETE BRIDGE THROUGH FIELD TESTING AND MONITORING". International Journal of Structural Stability and Dynamics 09, nr 04 (grudzień 2009): 711–28. http://dx.doi.org/10.1142/s0219455409003259.

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This paper presents field tests performed on a slab-on-girder pre-stressed concrete bridge. The bridge was tested under static loading, crawling loading, and dynamic loading. A full three-dimensional finite element prediction under both static and dynamic loadings was carried out and the results were compared with the field measurements. While acoustic emission (AE) monitoring of bridge structures is not a new vista, the method has not been fully exploited in bridge monitoring. Though numerous quantitative methods have been proposed, they have not yet developed to be useful for actual field tests of bridges. Therefore, in this study, an attempt was made to use the intensity analysis technique for damage quantification using the AE method.

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Wang, Yu Qian, Shou Shan Cheng, Wan Heng Li i Yi Li. "Investigation on the Index System for Durability of Concrete Bridges in Codes". Applied Mechanics and Materials 94-96 (wrzesień 2011): 1577–82. http://dx.doi.org/10.4028/www.scientific.net/amm.94-96.1577.

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This article surveys and studies the design, construction and verification codes related to durability of concrete bridges both home and abroad, contrastively analyzes their requirements on environmental effect, durability design, construction and testing indices, and finally brings up the durability index system suitable for Chinese concrete bridges which covers the four hierarchies of environment, material, components and structure, and also considers the three phases of design, construction and verification.

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Wang, Zhi Feng, Xian Yan Zhou i Da Hai Zhang. "Structural Condition Evaluation of an In-Service Glued-Laminated Timber Bridge Based on the Dynamic and Static Testing". Applied Mechanics and Materials 847 (lipiec 2016): 31–37. http://dx.doi.org/10.4028/www.scientific.net/amm.847.31.

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The structural use of wood has increased steadily in recent times, including a renewed interest in the use of timber as a bridge material. As the only environment-friendly and resource-saving building material, wood has been gradually uesd for short and medium span bridges in China. In 2014, The domestic largest single-span glued-laminated timber (glulam) deck arch bridge crossing a freeway was completed and put into operation in Zhangjiajie City, central China' Hunan province. In order to know the bearing capacity of superstructures and assess its working conditions, in-site static and dynamic testings has been carried out. Many measures including finite element simulation, field test and comparision between test results and calculated results have been employed to study responses of the bridge under static loads and dynamic loads as well. The researches indicate this glulam footbridge has performed well in service and appear to be cost effective when compared with the cost of installing traditional concrete and steel bridges.

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41

Flores, Elsy Y., Jordan Varbel, Craig M. Newtson i Brad D. Weldon. "Ultra-High-Performance Concrete Shear Keys in Concrete Bridge Superstructures". MATEC Web of Conferences 271 (2019): 07006. http://dx.doi.org/10.1051/matecconf/201927107006.

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Many existing bridges have adjacent girders that utilize grouted shear keys to transfer loads laterally across the superstructure. Cracking and leaking often cause degradation of the shear key and the girder. This work investigates the potential for using non-proprietary ultra-high performance concrete (UHPC) as a grouting material for repair of deteriorated shear keys by testing bond strength between UHPC and substrate concrete surfaces that were either formed or scarified by chipping. Bond strengths were adequate for both surface textures even though texture depth was substantially less than recommended by ACI 546. Scanning electron microscopy has also been used to investigate the bonded area. This microscopic scanning has shown fly ash residue remaining on the substrate after bond failure, indicating that the supplementary cementitious materials produce much of the bond. Ongoing work for this project also includes full-scale testing of UHPC shear keys between pre-stressed channel girders.

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Hao, Bao Hong, Ding Zeng, Quan Yong Deng, Xi Yang Song i Tin Tin Zhou. "Concrete Reinforcement Corrosion Characteristics and Grading Evaluation under Natural Conditions". Advanced Materials Research 1030-1032 (wrzesień 2014): 744–49. http://dx.doi.org/10.4028/www.scientific.net/amr.1030-1032.744.

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Abstract: The paper, by using various electrochemical methods, conducts non-destructive quantitative testing towards currently-used bridges, analyzes reinforcement corrosion characteristics under natural environment, concludes the influencing rule of natural environment on reinforcement corrosion, and reveals differences accelerated simulation environment by contrasting with preliminary laboratory results. The real bridge measurement results show that: weight loss ratio of reinforcement under humid environment can reach a maximum of 33% and a minimum of 18%; while weight loss ratio of reinforcement under dry environment falls between 8%-15%. The actual measurement results also show that: box girder and guard bar coated with waterproof layer help to protect reinforcing bars inside the concrete and effectively reduce the corrosion rate inside reinforcing bars with weight loss ratio around 4-8%. It contrasts the precision of two testing methods and comes to a conclusion that testing precision of linear polarization method is higher than that of impulse current method.

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Cheng, Yong Chun, Hong Bin Guo, Xian Qiang Wang i Yu Bo Jiao. "Durability Assessment of Reinforced Concrete Bridge Based on Fuzzy Neural Networks". Advanced Materials Research 838-841 (listopad 2013): 1069–72. http://dx.doi.org/10.4028/www.scientific.net/amr.838-841.1069.

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In the operation process of bridge structures, some bridges appear early failure without reaching design reference period due to the influences of external environment, vehicle load and other factors. Therefore, the problem of structure durability is very obvious. In this paper, a new durability assessment method is proposed based on fuzzy neural networks, which can take account of the defects and deficiencies of existing durability assessment methods. The simulation for learning and testing samples indicates that the proposed method possesses good learning ability and predictive analysis ability. Actual project verifies the effectiveness of the method

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Varela-Ortiz, Wilmel, Carmen Y. Lugo Cintrón, Gerardo I. Velázquez i Terry R. Stanton. "Load testing and GPR assessment for concrete bridges on military installations". Construction and Building Materials 38 (styczeń 2013): 1255–69. http://dx.doi.org/10.1016/j.conbuildmat.2010.09.044.

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Lantsoght, Eva, Cor van der Veen, Ane de Boer i Dick A. Hordijk. "Proof load testing of reinforced concrete slab bridges in the Netherlands". Structural Concrete 18, nr 4 (21.03.2017): 597–606. http://dx.doi.org/10.1002/suco.201600171.

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Haynes, Matthew A., Erdem Coleri i Shashwath Sreedhar. "Impermeable Asphalt Concrete Layer to Protect and Seal Concrete Bridge Decks". Transportation Research Record: Journal of the Transportation Research Board 2673, nr 6 (18.04.2019): 355–67. http://dx.doi.org/10.1177/0361198119841041.

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Deterioration of the concrete bridge deck is one of the most significant problems affecting the service life of bridges in the United States (U.S.). The early failure of asphalt pavement overlays on concrete bridge decks with spray-on waterproofing membranes has been recognized as a significant issue by the Oregon Department of Transportation (ODOT). Potential reasons for the failure of the asphalt overlays were thought to be the poor adhesion between the waterproofing membrane and the asphalt-wearing course, and the material properties of the asphalt layer. Moisture penetration into the asphalt overlay and standing water on the concrete bridge deck result in expansion and contraction at the interface on the bridge deck during freeze-thaw cycles. Expansion and contraction because of freeze-thaw cycles cause debonding at the interface and result in an increased rate of deterioration for the asphalt concrete overlay. Additionally, the de-icing salts used to prevent hazardous roadway surfaces in the winter permeate into the deck and cause corrosion of the steel reinforcement, weakening the structural integrity of the bridge. The main goal of this study is to develop an impermeable asphalt mixture with high cracking and rutting resistance that can seal and protect the concrete bridge deck by preventing water and de-icing salts from penetrating into the concrete deck. Permeability of developed asphalt mixtures was quantified by permeability testing and moisture sensor measurements. Rutting and cracking resistance of the developed impermeable asphalt mixture strategies were also evaluated by conducting flow number (FN) and semi-circular bend (SCB) tests in the laboratory.

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Ventura, C. E., A. J. Felber i S. F. Stiemer. "Determination of the dynamic characteristics of the Colquitz River Bridge by full-scale testing". Canadian Journal of Civil Engineering 23, nr 2 (1.04.1996): 536–48. http://dx.doi.org/10.1139/l96-058.

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This paper presents the results of full-scale tests performed at the Colquitz River Bridge near Victoria, British Columbia (B.C.), Canada, during September 1992 to determine the dynamic characteristics of the structure. The five-span bridge was completed in 1954 and is part of the Trans-Canada Highway. It is 82.68 m long and 11.89 m wide, and has six continuous steel girders supporting a 175 mm thick concrete deck. This particular bridge was chosen for testing because of its typical nature of many B.C. bridges, its location in an area of high seismic risk, and its excellent site accessibility. The tests included extensive measurements of ambient vibrations induced by traffic and other sources to determine the dynamic characteristics of the bridge. The most significant vertical and lateral mode shapes and associated periods of vibration were determined from vibration measurements at more than 50 different locations of the deck, piers, and abutments. Although a large amount of data were collected, they were quickly processed and analyzed with an innovative system developed at The University of British Columbia. One of the important features of this system is that it permits the identification of the principal modes of vibration immediately after the data have been collected. In addition to the ambient vibration tests, quick release pullback tests were conducted to verify modal frequencies determined from the ambient vibration tests and to determine the damping of the fundamental modes. These tests consisted of loading the bridge at a selected location with a force of about 90 kN and then releasing this load very quickly to induce free vibrations. The information obtained from the field tests was used to refine a computer finite element model of the bridge, which, in turn, was used to gain insight into the dynamic behaviour of specific components of the bridge. Further, this information was used later by the bridge owner to evaluate the bridge's expected response during an earthquake. Key words: steel bridges, dynamic response, full-scale tests.

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Yang, Yi Xi. "Study on Tensile Strains in Concrete Bridge Girders". Applied Mechanics and Materials 336-338 (lipiec 2013): 309–12. http://dx.doi.org/10.4028/www.scientific.net/amm.336-338.309.

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In this paper, we present the design and testing of a simple yet accurate transducer for measuring strain in reinforced concrete bridges. Lessons learned from two earlier versions of the transducer, the first of which was incorporated into the design constraints and criteria. The following sections present the transducer design process, review the calibration and lab testing of the transducer prototype, and summarize the transducer performance in the field.

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Novak, Josef, i Alena Kohoutkova. "Optimization of Pretensioned Steel Fiber Reinforced Concrete Beam". Advanced Materials Research 1106 (czerwiec 2015): 94–97. http://dx.doi.org/10.4028/www.scientific.net/amr.1106.94.

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Pretensioned concrete beams are used as a main load bearing member for composite bridges with a span to 30 m. The advantage of longitudinal prefabrication technology of beams for small span bridges is quick installation, savings of straight supporting scaffolding of centers and formwork. The amount of labour with formwork, reinforcement and concrete including work with scaffolding of centers on site is reduced at a minimum. During searching applications of steel fiber reinforced concrete (SFRC) suitable for this kind of structure a pretensioned concrete beam suitable for a bridge bay with a span from 12 to 15 m has been chosen for an investigation. Three types of beam were manufactured for experimental tests. The beams were supposed to be a part of a bridge bay with a composite slab. These pretensioned beams were made of SFRC. In case of the experimental tests, a cast-in place concrete cover from plain concrete was casted on the top of the beams. The cast-in place concrete cover simulated a top composite slab. The bearing capacity of the beams with the cast-in place concrete cover was tested until their destruction. The tested beams showed higher bearing capacity than it was determined by a theoretical calculation. The beams also demonstrated high safety against collapse during structure overloading. The process of the experimental testing was also simulated on a numerical nonlinear model and then the results were compared. The result comparison of the both types of tests did not show any significant irregularities.

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Haritos, Nicholas, Anil Hira, Priyan Mendis, Rob Heywood i Armando Giufre. "Load Testing to Collapse Limit State of Barr Creek Bridge". Transportation Research Record: Journal of the Transportation Research Board 1696, nr 1 (styczeń 2000): 92–102. http://dx.doi.org/10.3141/1696-49.

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VicRoads, the road authority for the state of Victoria, Australia, has been undertaking extensive research into the load capacity and performance of cast-in-place reinforced concrete flat slab bridges. One of the key objectives of this research is the development of analytical tools that can be used to better determine the performance of these bridges under loadings to the elastic limit and subsequently to failure. The 59-year-old Barr Creek Bridge, a flat slab bridge of four short continuous spans over column piers, was made available to VicRoads in aid of this research. The static testing program executed on this bridge was therefore aimed at providing a comprehensive set of measurements of its response to serviceability level loadings and beyond. This test program was preceded by the performance of a dynamic test (a simplified experimental modal analysis using vehicular excitation) to establish basic structural properties of the bridge (effective flexural rigidity, EI) and the influence of the abutment supports from identification of its dynamic modal characteristics. The dynamic test results enabled a reliably tuned finite element model of the bridge in its in-service condition to be produced for use in conjunction with the static testing program. The results of the static testing program compared well with finite element modeling predictions in both the elastic range (serviceability loadings) and the nonlinear range (load levels taken to incipient collapse). Observed collapse failure modes and corresponding collapse load levels were also found to be predicted well using yield line theory.

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