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Journal articles on the topic 'Bridge abutments'
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1
Alqarawi, Ahmed S., Chin J. Leo, D. S. Liyanapathirana, and Sanka Ekanayake. "Parametric Study on the Approach Problem of an Integral Abutment Bridge Subjected to Cyclic Loading due to Temperature Changes." Applied Mechanics and Materials 846 (July 2016): 421–27. http://dx.doi.org/10.4028/www.scientific.net/amm.846.421.
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Integral Abutment Bridges are widely utilized around the world because they offer a design alternative minimizing the potential construction and maintenance difficulties associated with expansion joints in other types of bridges. However, integral bridge systems also have certain issues that result from the absence of expansion joints. This is because temperature changes induce cycles of elongations and shortenings in the bridge deck which lead to rotational movements in bridge abutments against and away from the retained soil. This phenomenon may develop long term problems in terms of settlement of the backfill at the bridge approach and escalation in the lateral earth pressure acting on the bridge abutments. This paper aims to investigate the approach settlement and lateral earth pressure development in integral bridges abutments using finite element modelling of a concrete bridge abutment and the adjoining soil using the ABAQUS software. The paper presents a parametric study of the effects imposed by abutment movements on the retained soil. This study also investigates the effectiveness of using expanded polystyrene (EPS) geofoam inclusions as a remedial measure to minimize the approach settlement and lateral stress ratcheting effects in Integral Abutment Bridges.
2
Keller, Gordon R., and Steven C. Devin. "Geosynthetic-Reinforced Soil Bridge Abutments." Transportation Research Record: Journal of the Transportation Research Board 1819, no. 1 (January 2003): 362–68. http://dx.doi.org/10.3141/1819b-46.
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Geosynthetic-reinforced soil (GRS) bridge abutments have been used on a number of bridge projects over the past decade. This adaptation of reinforced soil technology to bridge structures and their approach fills offers an excellent opportunity to simplify construction, reduce construction time, and reduce cost on structures for which this technology is appropriate. This design concept, in which the actual bridge superstructure rests upon the GRS abutment wall, minimizes differential settlement and eliminates the problematic “bridge bump” found on many structures. The technology has been adapted to both road and trail bridges. The basic design concept of GRS used in bridge abutment applications was evaluated, along with its advantages and disadvantages. Some selected case histories of GRS bridge abutments on low-volume roads and trails in Alaska and California were considered. In addition, the Mammoth bridges, in the mountains of northern California, with high design snow loads and high horizontal peak ground accelerations, afforded an opportunity to design, construct, and monitor GRS-supported spread-footing abutments under difficult service conditions.
3
Husain, Iqbal, and Dino Bagnariol. "Design and Performance of Jointless Bridges in Ontario: New Technical and Material Concepts." Transportation Research Record: Journal of the Transportation Research Board 1696, no. 1 (January 2000): 109–21. http://dx.doi.org/10.3141/1696-14.
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It is well recognized that leaking expansion joints at the ends of bridge decks have led to the premature deterioration of bridge components. The elimination of these maintenance-prone joints not only yields immediate economic benefits but also improves the long-term durability of bridges. In Ontario, Canada, “jointless” bridges have been used for many years. Recently, the use of two main types of these bridges has increased dramatically. The first type is an “integral abutment” bridge that comprises an integral deck and abutment system supported on flexible piles. The approach slabs are also continuous with the deck slab. The flexible foundation allows the anticipated deck movements to take place at the end of the approach slab. Control joint details have been developed to allow movements at this location. The second type is a “semi-integral abutment” bridge that also allows expansion joints to be eliminated from the end of the bridge deck. The approach slabs are continuous with the deck slab, and the abutments are supported on rigid foundations (spread footings). The superstructure is not continuous with the abutments, and conventional bearings are used to allow horizontal movements between the deck and the abutments. A control joint is provided at the end of the approach slab that is detailed to slide in between the wing walls. Some of the design methods and construction details that are used in Ontario for integral and semi-integral abutment bridges are summarized. A review of the actual performance of existing bridges is also presented.
4
Rashidi, Maria, Chunwei Zhang, Maryam Ghodrat, Shaun Kempton, Bijan Samali, Ali Akbarnezhad, and Limeng Zhu. "Bridge Abutment Movement and Approach Settlement — A Case Study and Scenario Analysis." International Journal of Structural Stability and Dynamics 18, no. 08 (August 2018): 1840011. http://dx.doi.org/10.1142/s0219455418400114.
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Movement of bridge abutment is a significant issue affecting the overall reliability and safety of the structure. However, despite considerable consequences, potential movement of abutment is usually not considered in design of bridges for serviceability and abutments are generally designed as fixed elements. Theoretical analysis of bridge abutment and deck design provides background knowledge of reactions that should be anticipated and accounted for. Case studies of bridges experiencing movements and rotations show that practical outcomes often deviate from theoretical expectations. The research presented in this paper, aims to develop a better understanding of abutment stability from both a design and maintenance point of view. This paper includes an in-depth case study of the Kanahooka Road Overbridge in New South Wales, Australia. The results of a full bridge inspection leading to identification of multiple serviceability issues caused by movement of abutments are presented. Moreover, a systematic methodology is implemented, to identify potential remedial options for treatment of abutment movement. The knowledge gained through this case study has led to the development of a model for the management of abutment movement.
5
Huntley, Shelley A., and Arun J. Valsangkar. "Field monitoring of earth pressures on integral bridge abutments." Canadian Geotechnical Journal 50, no. 8 (August 2013): 841–57. http://dx.doi.org/10.1139/cgj-2012-0440.
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Integral abutment bridges have become a successful alternative to the traditional design procedure of using expansion joints to balance the thermal movements of bridge structures. However, there are many design and detailing variations, and uncertainties exist about the soil–structure interaction of the integral abutments. Therefore, field data from pressure cells installed behind the abutments of a 76 m long, two-span, pile-supported integral abutment bridge are the focus of this paper. The data on external displacements of the abutments are also reported. The applicability of using common theoretical passive earth pressure coefficients is assessed and it appears that the traditional methods of Coulomb and Rankine are not the best approach for predicting the earth pressure envelope. Additionally, over the monitoring period of three years, it was found that a definite conclusion regarding the ratcheting of lateral earth pressure could not be established for this bridge site. Finally, comparisons to earth pressures measured at other field studies indicate variability in the earth pressure distribution, magnitude, and behaviour over time, as these are dependent on several factors distinctive to each bridge site.
6
Heydarpour, Khashayar, and Payam Tehrani. "Influence of Abutment Stiffness and Strength on the Seismic Response of Horizontally Curved RC Bridges in Comparison with Equivalent Straight Bridges at Different Seismic Intensity Levels." Shock and Vibration 2022 (November 25, 2022): 1–21. http://dx.doi.org/10.1155/2022/3532331.
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Seismic design codes have imposed some limitations on the maximum subtended angle of curved bridges and allow engineers to analyze and design them using an equivalent straight bridge. This paper investigates these limitations and evaluates the AASHTO code recommendations regarding the prediction of the seismic responses of curved bridges using an equivalent straight bridge for bridges with different abutment properties at different seismic hazard levels. In this regard, the seismic responses of 21 horizontally curved and straight RC four-span bridges with different abutment types are investigated. In 7 bridge models, soil-abutment-bridge interaction is neglected, while in the rest of the bridge models, the seat-type abutments with the participation of the nonlinear backfill soil, gap, and abutment piles are used in structural modeling. First, nonlinear static (pushover) analyses are carried out to evaluate the overall behavior of the bridges with different abutment configurations in the two perpendicular principal directions. Subsequently, nonlinear time history analyses are performed to predict the seismic response of bridge elements, including column drifts and deck displacements at the place of the abutments in the radial and tangential directions at different seismic intensity levels, including the design basis earthquake (DBE) and maximum credible earthquake (MCE) excitation levels. In addition, the actual maximum displacements of the components of the bridges (i.e., the total absolute displacements) were also predicted and evaluated for different cases. It was found that the abutment properties and boundary conditions had a significant effect on the seismic response assessment of curved bridges compared to straight bridges, while such parameters are not currently considered by the design codes. The results also indicated that by increasing the seismic intensity level, more limitations should be imposed on the use of the equivalent straight bridges.
7
Deng, Yulin, Shuxun Ge, and Fan Lei. "Effects of Pounding and Abutment Behavior on Seismic Response of Multi-Span Bridge Considering Abutment-Soil-Foundation-Structure Interactions." Buildings 13, no. 1 (January 16, 2023): 260. http://dx.doi.org/10.3390/buildings13010260.
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This study aims to analyze the longitudinal seismic performance of a typical multi-span continuous girder bridge with seat-type abutments under earthquake excitation, especially accounting for different abutment behaviors. Three-dimensional finite element models of typical multi-span bridges are built considering the nonlinearity of the bridge columns, bearings, abutment-backfill interactions, pile-soil interactions, and the pounding at expansion joints. One of the models adopts a simplified bilinear model to express the force-displacement relationship of the abutment backwall. The other adopts a more practical multi-linear model, and the abutment backwall is used as a sacrificial component to control the damage to the abutment’s foundation by changing the strength of the abutment backwall. Comparisons of the results of the analysis of two bridge models with and without a sacrificial backwall indicate that it is more favorable for bridges with a sacrificial backwall to protect the foundation, but it is likely to arouse a larger displacement response of the main beam and even cause the unseating of girders. The recommendation for a sacrificial abutment in seismic design is that the right yield strength of the backwall should be selected to reach the balance point of force and displacement, and a collapse-proof system could be employed to prevent the beam from unseating.
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Paikun, Amir Hamzah, Selfin Anugrah Amdania, and Shcherbak Petr Nikolaevich. "Analysis of abutment safety factors against landslides on the Cipeundeuy bridge - Sukatani, Indonesia." INTERNATIONAL JOURNAL ENGINEERING AND APPLIED TECHNOLOGY (IJEAT) 4, no. 1 (May 29, 2021): 1–10. http://dx.doi.org/10.52005/ijeat.v4i1.46.
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Bridges are connecting access between one region and another, and play an important role in transportation to facilitate community economic activities. The river bridge has very steep cliffs, and these cliffs often occur in landslides, therefore this study is very important to determine the safety of the bridge. This study aims to determine the safety of the bridge abutment structure which is the head of the bridge with the function of continuing the load on the bridge foundation. This analysis is limited to only calculating the stability and safety of bridge abutments with reinforced concrete structures. The analysis uses methods and formulas referring to Indonesian national standards, namely RSNI T-02-2005 regarding loading for bridges, RSNI T-12-2004 concerning concrete structure planning for bridges, SNI 03-2833-200X concerning earthquake resistance planning standards for bridges. The data used are drawing data and technical specifications used on the bridge, then the data is verified against planning consultants, project implementers, and observations at the location. The results of the analysis stated that the bridge abutment was declared safe from soil thrust and other forces, but did not have a good safety factor against shear forces. Landslides that occur can be resisted by the bridge abutments. This research is expected to be followed up by policymakers to repair bridges so that they are resistant to maximum shear forces, and provide safety signs from landslides to relieve public anxiety when crossing bridges, as well as provide reinforcement for the cliffs around the bridge.
9
Awad Ibnouf, Omer, and Eltayeb Hassan Onsa. "Effects of temperature changes on voided slab integral abutment bridge." FES Journal of Engineering Sciences 9, no. 1 (February 22, 2021): 104–11. http://dx.doi.org/10.52981/fjes.v9i1.666.
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Integral Abutment Bridges (IABs) are joint-less bridges whereby the deck is monolithic with the abutment walls. IABs are outperforming their non-integral counterparts in economy and safety. Thermal effects introduce significantly complex and nonlinear soil-structure interaction into the response of abutment walls and piles of the IB. This paper carried out comprehensive study on voided slab system with five spans bridge each span is 17m long. The bridge has been modelled using SAP software. The abutments and pile foundations are modeled taking into consideration the soil-structure interaction. The study covered a design uniform temperature change of (10, 20, 30, 40 and 50) °C. To gain a better understanding of the mechanism of load transfer due to thermal actions, a 3D frame anal¬ysis is carried out on the above mentioned IABs. The results showed wide range of different linear and lightly non-linear relationships between temperature range, deformations and moments. The paper highlighted the serious effect of the deformations resulting from the repeated temperature change which causes drop in soil or bombing at the abutments ~ embankment contact zone.
10
M. Dicleli. "Computer-aided limit states analysis of bridge abutments." Electronic Journal of Structural Engineering 1, no. 1 (January 1, 2001): 74–97. http://dx.doi.org/10.56748/ejse.1161.
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This paper presents a computer program developed for limit states analysis of abutments. The program can perform both structural and geotechnical analysis of bridge abutments and check their resistances in compliance with limit states design criteria. In the program, the earth pressure coefficient for the backfill soil is calculated as a function of abutment’s lateral non-linear displacement. Therefore, for abutments partially restrained against lateral movement, an earth pressure coefficient less than that of at-rest conditions may be obtained. This may result in a more economical design.
11
Yunus, Muhammad, and Zharin F. Syahdinar. "Stability Analysis of Aifa Bridge Abutment in Fafurwar District, Bintuni Bay Regency, West Papua Province." EPI International Journal of Engineering 2, no. 2 (August 31, 2019): 162–71. http://dx.doi.org/10.25042/epi-ije.082019.12.
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In the construction of public works infrastructure, especially road infrastructure works, bridge construction work plays a very important role besides the construction of the road itself. One of the things that deserves the attention of the planners in designing a bridge structure is the design of the substructure, this is because the substructure determines the quality and service life of a bridge. In addition, at present many cases of bridge structure failures are caused by failures of the substructure in holding the load acting on the bridge. The aim of this study was to determine the stability of the abutment to sliding failure and the stability of the abutment to overturning failure on the construction of the Aifa bridge in the Bintuni Bay Regency. From the results of the calculation of the stability of the abutments to sliding failure, when the abutments are in normal conditions was obtained safety factor (SF) values 1,907, in condition of the upper structure load is not working was obtained safety factor (SF) values 1,045 and during earthquake conditions was obtained safety factor (SF) values 1,419. While the results of the calculation of the stability of the abutments to overturning failure, when the abutments are in normal conditions was obtained safety factor (SF) values 4,640, in condition of the the upper structure load is not working was obtained safety factor (SF) values 1,658 and during earthquake conditions was obtained safety factor (SF) values 3,159. Because obtained safety factor (SF) values greater than 1, so that the stability of the abutment is safe to sliding failure and overturning failure.
12
Maleki, Shervin, and Alireza Siadat. "The Response Modification Factor for Seismic Design of Integral Abutment Bridges." Journal of Civil Engineering and Construction 10, no. 3 (August 15, 2021): 140–53. http://dx.doi.org/10.32732/jcec.2021.10.3.140.
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The response modification factor (R factor) is a crucial parameter for calculating the design seismic forces applied to a bridge structure. This factor considers the nonlinear performance of bridges during strong ground motions. Conventional bridge structures rely on the substructure components to resist earthquake forces. Accordingly, there are R factors available in the design codes based on the type of bridge substructure system. Lateral load resisting system of Integral Abutment Bridges (IABs) in the longitudinal direction is more complex than ordinary bridges. It involves the contributions from soils behind the abutments and soil/structure interaction (SSI) in addition to existing rigid connection between the superstructure and abutments. There is no R factor available in any design code throughout the world for IABs in the longitudinal direction that considers all these parameters. In this research, the Federal Emergency Management Agency publication FEMA P695 methodology has been applied to estimate the R factor for IABs. It is found that 3.5 could be a safe and valid R factor in the longitudinal direction for seismic design of such bridges.
13
Huntley, Shelley A., and Arun J. Valsangkar. "Behaviour of H-piles supporting an integral abutment bridge." Canadian Geotechnical Journal 51, no. 7 (July 2014): 713–34. http://dx.doi.org/10.1139/cgj-2013-0254.
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Integral abutment bridges accommodate thermal superstructure movements through flexible foundations rather than expansion joints. While these structures are a common alternative to conventional design, the literature on measured field stresses in piles supporting integral abutments appears to be quite limited. Therefore, field data from strain gauges installed on the abutment foundation piles of a 76 m long; two-span integral abutment bridge are the focus of this paper. Axial load, weak- and strong-axis bending moments of the foundation piles, as well as abutment movement and backfill response, are presented and discussed. Results indicate that the abutment foundation piles are bending in double curvature about the weak axis, as a result of thermal bridge movements, and bending also about the strong axis due to tilting of the abutments. A simple subgrade modulus approach is used to show its applicability in predicting behaviour under lateral loading. In the past, much emphasis has been placed on the lateral displacements of piles and less on variations of axial load. In this paper, a new hypothesis, which offers insight into the mechanisms behind the observed thermal variations in axial load, is proposed and assessed. The data from the field monitoring are also compared with the limited data reported in the literature.
14
Choi, Byung H., Lorenz B. Moreno, Churl-Soo Lim, Duy-Duan Nguyen, and Tae-Hyung Lee. "Seismic Performance Evaluation of a Fully Integral Concrete Bridge with End-Restraining Abutments." Advances in Civil Engineering 2019 (March 27, 2019): 1–12. http://dx.doi.org/10.1155/2019/6873096.
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A fully integral bridge that is restrained at both ends by the abutments has been proposed to form a monolithic rigid frame structure. Thus, the feasible horizontal force effect due to an earthquake or vehicle braking is mainly prevented by the end-restraining abutments. In a recent study, a fully integral bridge with appropriate end-restraining abutment stiffness was derived for a multispan continuous railroad bridge based on linear elastic behavior. Therefore, this study aims to investigate the nonlinear behavior and seismic capacity of the fully integral bridge and then to assess the appropriate stiffness of the end-restraining abutment to sufficiently resist design earthquake loadings through a rigorous parametric study. The finite element modeling and analyses are performed using OpenSees. In order to obtain the force-deflection curves of the models, nonlinear static pushover analysis is performed. It is confirmed that the fully integral bridge prototype in the study meets the seismic performance criteria specified by Caltrans. The nonlinear static pushover analysis results reveal that, due to the end-restraining effect of the abutment, the lateral displacement of the fully integral bridge is reduced, and the intermediate piers sustain less lateral force and displacement. Then, the sectional member forces are well controlled in the intermediate piers by a proper application of the end-restraining abutments.
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Kumcu, Şerife Yurdagül, Mustafa Gögüş, and Mehmet Ali Kökpinar. "Temporal scour development at bridge abutments with a collar." Canadian Journal of Civil Engineering 34, no. 4 (April 1, 2007): 549–56. http://dx.doi.org/10.1139/l06-146.
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This study investigated the reduction of scour around a vertical-wall bridge abutment using rectangular collars for clear-water flow conditions over uniform sediment particles in a laboratory flume. Collars of different sizes and at different elevations were tested to determine the temporal variation of scour depth around the bridge abutment. The development of scour around the abutments with and without a collar for a time period of 6 h was studied, and observed scour depths were compared. Experimental results showed that, in addition to protecting the abutments against erosion, the addition of a collar is effective in reducing the rate of temporal scour development. A comparison of the present results with those from previous studies revealed that the effectiveness of a collar increases with a decrease in the elevation of the collar and an increase in the width of the collar.Key words: bridge abutment, collar, experimentation, hydraulics, scour, temporal variation.
16
Xu, Ming, Chris RI Clayton, and Alan G. Bloodworth. "The earth pressure behind full-height frame integral abutments supporting granular fill." Canadian Geotechnical Journal 44, no. 3 (March 1, 2007): 284–98. http://dx.doi.org/10.1139/t06-122.
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Compared with conventional bridges, integral bridges have no bearings or joints between the deck and abutments and thus can significantly reduce maintenance requirements and costs over the bridge's lifetime. However, there is uncertainty about the ultimate magnitude of the lateral earth pressure behind such abutments, as they are forced to move with the deck length change caused, for example, by daily and annual variations in the effective bridge temperature. This research investigated the earth pressure that would be expected to occur behind full-height frame integral abutments backfilled by granular materials. Radial strain-controlled cyclic stress path testing has been conducted on coarse sand specimens and a glass ballotini specimen. The results suggest that for integral abutments retaining uniform coarse sand, the lateral earth pressure will experience systematic increases for almost all cyclic strain levels, eventually reaching states of stress close to both active and passive. The mechanism of the buildup of lateral stress is explored, and it appears to be associated with nonspherical granular particle shape. The implications for frame integral abutment design are discussed.Key words: integral abutments, granular, particle shape, earth pressure, stiffness.
17
Awad, Mohammed, and Tian Lai Yu. "Computer Modeling and Parametric Study of Thermal Effects in Integral Abutment Bridge." Advanced Materials Research 446-449 (January 2012): 733–38. http://dx.doi.org/10.4028/www.scientific.net/amr.446-449.733.
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Structural behavior of concrete integral abutment bridge subjected to temperature rise was investigated through a numerical modeling and parametric study. Long-term, field monitoring through the summer was performed on Industrial Park Bridge located in Heilongjiang province, China from June 13, 2010 until June 28, 2010. The collected data was used to validate the accuracy of a 3D-finite element model of the bridge which took into account soil-structure interaction. Based on the calibrated finite element model a parametric study considered two parameters, bridge length and abutment height, was carried out to investigate the effects of this parameters on structural behavior of integral abutment bridge subject to temperature rise. It was determined that Thermal load in the superstructure of the integral bridge develop significant magnitudes of bending and axial forces in the superstructure. The largest magnitude of thermally induced moment always occurs near the abutment, and axial force is constant across the length of each span. For bridge thermal expansion, longer bridges and taller abutments cause larger thermally induced superstructure axial force due to development of higher backfill pressure. Generally span length has a higher influence for thermally induced superstructure forces in terms of axial force and bending moment than the abutment height.
18
Hearn, George, and Knut Nordheim. "Differential Settlements and Inelastic Response in Steel Bridge Beams." Transportation Research Record: Journal of the Transportation Research Board 1633, no. 1 (January 1998): 68–73. http://dx.doi.org/10.3141/1633-09.
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A proposed method for mitigation of pavement faults at bridge abutments (the “bump at the end of the bridge”) is the use of shallow foundations. Abutments on shallow foundations are expected to settle compatibly with embankments and thus to minimize pavement faults. Allowing bridge abutments to settle may reduce faults, but it creates a demand for tolerance of different settlement in bridge superstructures. Current guidelines for tolerable differential settlement of bridges are empirical only, and the application of elastic analysis of bridge superstructures to determine tolerance of settlement has not produced satisfactory results. Inelastic analysis of steel bridge beams was applied to the computation of tolerable differential settlement. Tests of inelastic rotation capacity of steel beams were reviewed and compared with the results of inelastic analyses. A model of tolerable inelastic rotation capacity in steel beams is proposed.
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Vasconez, Rosa, Aliaksei Kustau, and Husam Najm. "An overview of integral abutments: Current practices, field monitoring and deck replacement measures." Bridge Structures 18, no. 1-2 (September 28, 2022): 27–43. http://dx.doi.org/10.3233/brs-220196.
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The use of integral abutments in bridges goes back many years to the late 1930’s in the United States. Over the years, integral bridges became more popular as more and more states built those bridges and more engineers became familiar with their design and construction. These bridges are being built in Europe since the 1980’s. An integral abutment bridge acts as a frame structure with a continuity connection between the superstructure and the substructure. The substructure is typically an integral cap supported on single row of piles that provides flexibility to accommodate thermal loads and displacements. The main advantage of integral abutment bridges is that they are built without expansion joints which eliminates maintenance costs and reduces construction costs. Because of the interaction between the soil and the integral abutment under the applied loads and the cyclic nature of thermal loads, the analysis and design of integral abutment bridges can be, in some cases, challenging especially when the designs falls outside the geometrical limits set by existing standards. This overview focus on field performance data reported in the literature and interpretation of this data. IT also highlights the needs for more test data during construction and for long term performance under cyclic thermal movements. Deck replacement requirements in integral abutments were investigated using analytical models and recommendations for deck replacement preparations are provided.
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Wu, Peng, Faye Hirshfield, and Jueyi Sui. "Further studies of incipient motion and shear stress on local scour around bridge abutment under ice cover." Canadian Journal of Civil Engineering 41, no. 10 (October 2014): 892–99. http://dx.doi.org/10.1139/cjce-2013-0552.
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An experimental study was conducted to investigate the scour development around bridge abutments under ice cover with non-uniform natural sands. Two abutments and three non-uniform sediments were used in the research. The mechanism of incipient motion for non-uniform sediments under ice cover was analyzed. By introducing scour angles around two abutments, a relationship between maximum scour depth and velocity was established for clear-water scour under ice cover. Dimensionless shear stress was also calculated and compared with shear Reynolds number for non-uniform sediments. The maximum scour depth and dimensionless shear stress were investigated under both open channel, smooth cover and rough covered conditions. Results show that around the square abutment, the scour angle is smaller than that of the semi-circular abutment. For clear water scour, the maximum scour depth increases due to the presence of ice cover.
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Bertok, J. "Settlement of embankments and structures at Vancouver International Airport." Canadian Geotechnical Journal 24, no. 1 (February 1, 1987): 72–80. http://dx.doi.org/10.1139/t87-007.
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This paper presents a case record of the settlement observations of road approach embankment and bridge and overpass abutments built on deep, soft, compressible, deltaic deposits at Vancouver International Airport. The field data are analysed, the observed settlements are compared with calculated predictions, and conclusions are presented. Key words: road embankment, bridge abutment, settlement, observation, prediction, interpretation.
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Liao, Li Ping, Ying Yan Zhu, D. H. Steve Zou, Zhi Quan Yang, Waseem Muhammad, Ji Ding Chen, Yun Wang, and Chen Yin Ye. "Key Point of Bridge Damage Caused by Glacial Debris Flows along International Karakorum Highway, Pakistan." Applied Mechanics and Materials 256-259 (December 2012): 2713–23. http://dx.doi.org/10.4028/www.scientific.net/amm.256-259.2713.
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Glacial debris flows along International Karakorum Highway (KKH) connecting northern Pakistan with China, are always causing so extreme threats to a majority of bridges built along KKH. So the improvement project of KKH has been being carried out by China Road & Bridge Corporation in 2008. However it is necessary to collect the detailed data about the damages to bridges and obtain the most dangerous key position. The series of field investigations from 2008 to 2011 demonstrate that the damages are classified into four categories: deposition under bridge, abrasive erosion, impact on piers or abutment and collapse due to buoyancy. Statistics indicate deposition under bridge is the most dominant damage whereas the most serious damage is the impact on piers or abutments. Therefore a case study on key point is made for the typical bridge subjected to impact from Ghulkin glacial debris flow. Finally prevention measures are given.
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Miller, R., T. M. Baseheart, and R. Sprague. "Use of High-Performance Concrete for Bridge Abutments: A Case Study." Transportation Research Record: Journal of the Transportation Research Board 1740, no. 1 (January 2000): 19–24. http://dx.doi.org/10.3141/1740-03.
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As part of an FHWA program to use high-performance concrete (HPC) in bridges, the state of Ohio constructed an adjacent box girder HPC bridge. HPC was used both for the prestressed and precast girders and for the cast-in-place abutments. The abutment mix was primarily designed for durability by using a low water-to-cementitious material ratio and pozzolanic materials. Before construction, laboratory trial mixes were run by using the actual material that was to be used in the abutments. After verifying the suitability of the mix in the laboratory, a few large trial batches were made at the ready-mix concrete plant to verify the plastic and hardened properties of the mix. During construction of the bridge, several problems occurred. Just before construction began, the coarse aggregate failed the state inspection and a new source of coarse aggregate had to be found. Unfortunately, HPC is sensitive to changes in aggregate, but there was no time to create trial batches before construction began. As a result, the mix had to be adjusted during construction. Soon after the initial abutment pours were made, differential shrinkage cracking was found. This was due to problems with inadequate curing. After a few tries, the mix problems were corrected and proper curing eliminated most of the cracking. Specific recommendations for quality control are made on the basis of the experience gained.
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Arsoy, Sami, J. M. Duncan, and R. M. Barker. "Approach to Evaluating Damage from Thermal Bridge Displacements." Transportation Research Record: Journal of the Transportation Research Board 1936, no. 1 (January 2005): 124–29. http://dx.doi.org/10.1177/0361198105193600115.
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Bridges are subject to daily and seasonal thermal displacement cycles. In conventional bridges, expansion joints are used to accommodate these displacements. However, in integral bridges, the expansion joints are eliminated, and the superstructure, along with the bridge abutments, undergoes displacements during each temperature cycle. A practical approach to model both daily and seasonal temperature cycles was proposed. The effectiveness of the proposed approach was verified by conducting large-scale laboratory tests on segments of a bridge abutment supported by two different pile types: an H-pile and a prestressed reinforced concrete pile. The results of the tests have shown that the proposed method is practical and capable of detecting damage mechanisms induced by daily thermal displacement cycles. Test results also have shown that damage from daily thermal displacements is more pronounced in materials with nonlinear stress–strain properties.
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Lv, Dan, Da Jun Zhao, Long Li, and Chuan Feng Zheng. "Solving Internal Forces of Piles of Jointless Bridges under the Action of Temperature Using Ordinary Differential Systems." Advanced Materials Research 1082 (December 2014): 220–23. http://dx.doi.org/10.4028/www.scientific.net/amr.1082.220.
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Temperature effect has a great effect on the force and deformation of bridge abutments, piles and filling at back abutment of jointless bridges. It’s necessary to definitude calculation model when using the finite element method to analyze these matter, but there is still no scientific approach to design jointless bridges. A method that solving internal forces of piles of jointless bridges under the action of temperature using ordinary differential equations is advanced in this paper. Differential equation of each rod of jointless bridges is established based on material mechanic, and then all differential equations form a differential systems. The internal force and deformation of the bridge are getted by solving differential equations based on boundary conditions, deformation coordination of rod coupling points and internal force equilibrium conditions, which is clear and definite.
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Duncan, J. M., and Sami Arsoy. "Effect of Bridge-Soil Interaction on Behavior of Piles Supporting Integral Bridges." Transportation Research Record: Journal of the Transportation Research Board 1849, no. 1 (January 2003): 91–97. http://dx.doi.org/10.3141/1849-11.
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As the temperature of an integral bridge changes, the length of the bridge increases and decreases, so that the abutments are pushed against the approach fill and then pulled away, causing lateral deflections at the tops of the piles that support the bridge. As a result, complex interactions take place among the abutment, the approach fill, the foundation soil, and the piles supporting integral bridges. Finite element analyses were performed to investigate these complex interactions. The results of this study indicate that these interactions have a beneficial effect on the stresses in the piles supporting the bridges. Because of these interactions, the foundation soil acts as if it were softer, resulting in reduced shear and moment in the piles at a given amount of deflection at the tops of the piles and therefore reduced stresses in the piles.
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Shreya Shetty, Karunakar Shetty, Raghad Tayeb, Jumana Abdou, Badariya Fetaihi, and Khamrunissa Hussain Sheikh. "Comparative Evaluation of Esthetic Materials Used for Fixed Partial Prosthesis Placed On Vital Abutments on The Periodontal Status: A One Year Retrospective Follow-Up." International Healthcare Research Journal 3, no. 5 (August 24, 2019): 179–84. http://dx.doi.org/10.26440/ihrj/0305.08271.
Full textAbstract:
BACKGROUND: The replacement of missing teeth with fixed partial dentures is largely dependent upon the health and stability of the surrounding periodontal structures. FPDs are often prepared on vital teeth as abutments. Esthetic materials have become popular in fixed prosthodontics today.
AIM: The present study aimed to assess the long term effect and tissue responses of various types of fixed partial prosthesis placed on vital abutment teeth on the periodontal parameters both clinically and radiographically.
MATERIALS AND METHOD: Following ethical committee approval, the study group comprised of 87 abutment teeth in 41 systemically healthy patients (24 males and 17 females) aged between 18 – 45 years who had received 3 unit fixed prosthesis(IPS empress, PFM or zirconia), having equigingival margins using vital teeth as abutments. The following parameters were assessed at the time of bridge placement and 1 year follow up – CAL, Probing depth, Distance between CEJ/ cervical crown margin and alveolar crest of the abutment teeth(radiograph).
RESULTS: Statistical analysis carried out by SPSSV22 software revealed significant changes in clinical parameters with IPS empress and radiographic parameters with PFM and Zirconia from time of bridge placement till the 1 year follow up.(P<0.05).
CONCLUSION: There seemed to be favorable responses of the periodontal tissues to the various esthetic materials used on vital abutments of FPDs.
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Lawver, Andrew, Catherine French, and Carol K. Shield. "Field Performance of Integral Abutment Bridge." Transportation Research Record: Journal of the Transportation Research Board 1740, no. 1 (January 2000): 108–17. http://dx.doi.org/10.3141/1740-14.
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The behavior of an integral abutment bridge near Rochester, Minnesota, was investigated from the beginning of construction through several years of service by monitoring more than 180 instruments that were installed in the bridge during construction. The instrumentation was used to measure abutment horizontal movement, abutment rotation, abutment pile strains, earth pressure behind abutments, pier pile strains, prestressed girder strains, concrete deck strains, thermal gradients, steel reinforcement strains, girder displacements, approach panel settlement, frost depth, and weather. In addition to determining the seasonal and daily trends of bridge behavior, live-load tests were conducted. All of the bridge components performed within the design parameters. The effects from the environmental loading of solar radiation and changing ambient temperature were found to be as large as or larger than live-load effects. The abutment was found to accommodate superstructure expansion and contraction through horizontal translation instead of rotation. The abutment piles appeared to be deforming in double curvature, with measured pile strains on the approach panel side of the piles indicating the onset of yielding.
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Long, James H., Scott M. Olson, Timothy D. Stark, and Emile A. Samara. "Differential Movement at Embankment-Bridge Structure Interface in Illinois." Transportation Research Record: Journal of the Transportation Research Board 1633, no. 1 (January 1998): 53–60. http://dx.doi.org/10.3141/1633-07.
Full textAbstract:
Settlement of roadway pavement surfaces near highway bridge abutments often leads to abrupt grade differences at the abutments. These grade differences subject vehicles to a bump, which may lead to driver discomfort and potentially unsafe driving conditions. Furthermore, differential movement requires costly and repeated maintenance work that usually impedes the flow of traffic. The sources of differential movement in Illinois can be divided into six major categories: ( a) compression or erosion of materials at the approach embankment-abutment interface, ( b) a broken approach slab, ( c) compression of foundation soils, ( d) compression or internal erosion of embankment soils, ( e) poor construction grade control, and ( f) areal distortion of foundation soils. An approach gradient equal to or greater than 1/100 to 1/125 appears to cause rider discomfort and therefore is proposed as a criterion for initiating remedial measures.
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Ettema, Robert, Bart S. Bergendahl, Atsuhiro Yorozuya, and Pelin Idil-Bektur. "Breaching of Bridge Abutments and Scour at Exposed Abutment Columns." Journal of Hydraulic Engineering 142, no. 10 (October 2016): 06016010. http://dx.doi.org/10.1061/(asce)hy.1943-7900.0001159.
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Fausett, Robert W., Paul J. Barr, and Marvin W. Halling. "Live-Load Testing Application Using a Wireless Sensor System and Finite-Element Model Analysis of an Integral Abutment Concrete Girder Bridge." Journal of Sensors 2014 (2014): 1–11. http://dx.doi.org/10.1155/2014/859486.
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As part of an investigation on the performance of integral abutment bridges, a single-span, integral abutment, prestressed concrete girder bridge near Perry, Utah was instrumented for live-load testing. The live-load test included driving trucks at 2.24 m/s (5 mph) along predetermined load paths and measuring the corresponding strain and deflection. The measured data was used to validate a finite-element model (FEM) of the bridge. The model showed that the integral abutments were behaving as 94% of a fixed-fixed support. Live-load distribution factors were obtained using this validated model and compared to those calculated in accordance to recommended procedures provided in the AASHTO LRFD Bridge Design Specifications (2010). The results indicated that if the bridge was considered simply supported, the AASHTO LRFD Specification distribution factors were conservative (in comparison to the FEM results). These conservative distribution factors, along with the initial simply supported design assumption resulted in a very conservative bridge design. In addition, a parametric study was conducted by modifying various bridge properties of the validated bridge model, one at a time, in order to investigate the influence that individual changes in span length, deck thickness, edge distance, skew, and fixity had on live-load distribution. The results showed that the bridge properties with the largest influence on bridge live-load distribution were fixity, skew, and changes in edge distance.
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Lugas, Andrea T., Mara Terzini, Elisabetta M. Zanetti, Gianmario Schierano, Carlo Manzella, Domenico Baldi, Cristina Bignardi, and Alberto L. Audenino. "In Vitro Simulation of Dental Implant Bridges Removal: Influence of Luting Agent and Abutments Geometry on Retrievability." Materials 13, no. 12 (June 21, 2020): 2797. http://dx.doi.org/10.3390/ma13122797.
Full textAbstract:
Implant fixed dental prostheses are widely used for the treatment of edentulism, often preferred over the screw-retained ones. However, one of the main features of an implant-supported prosthesis is retrievability, which could be necessary in the case of implant complications. In this study, the retrievability of implant-fixed dental prostheses was investigated considering two of the main factors dental practitioners have to deal with: the abutments geometry and the luting agent. Impulsive forces were applied to dental bridge models to simulate crowns’ retrievability in clinical conditions. The number of impulses and the impulsive force delivered during each test were recorded and used as retrievability indexes. One-hundred-and-five tests were conducted on 21 combinations of bridges and luting agents, and a Kruskal-Wallis test was performed on the results. The abutment geometry significantly influenced the number of impulses needed for retrieval (p < 0.05), and a cement-dependent trend was observed as well. On the other hand, the forces measured during tests showed no clear correlation with bridge retrievability. The best retrievability was obtained with long, slightly tapered abutments and a temporary luting agent.
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Tian, Wei, and Xue Dong Guo. "Finite Element Analysis and Reinforcement of Gravity Abutments Cracking." Applied Mechanics and Materials 405-408 (September 2013): 771–74. http://dx.doi.org/10.4028/www.scientific.net/amm.405-408.771.
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Cracking is a common problem existing in highway bridge abutments. Combing with projects, cracking reasons of one oblique U-type gravity abutment are analyzed by using a large and commonly used finite element software-FEM in this paper; in addition, preventive methods are put forward which can act as references for designing and constructions.
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Ghobarah, A. "Seismic behaviour of highway bridges with base isolation." Canadian Journal of Civil Engineering 15, no. 1 (February 1, 1988): 72–78. http://dx.doi.org/10.1139/l88-008.
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A study is made on the seismic behaviour of highway bridges with lead–rubber base isolation. The system of base isolation is considered as a bilinear spring. Single- and two-span highway bridges subjected to representative strong earthquake ground motion records were analyzed. The effect of various parameters such as the isolator's stiffness, pier stiffness, and pier eccentricity on the system response was evaluated.It was found that the use of base isolation shifts the fundamental frequency of the bridge system towards the longer period. Proper design of the base isolation tends to reduce the design forces on the bridge piers and is accompanied by larger displacements. Simplified design guidelines are adequate as long as the bridge system can be represented by a single degree of freedom model. The reduction in pier stiffness of a two-span bridge may increase the displacement and the force transmitted to the abutment. The increased forces at the abutments are accompanied by reduction in the shear force transmitted to the pier. Increased displacements and forces may also result when the location of the pier departs from the centre and unequal spans are created. In this case, the maximum displacements and forces occur at the abutment adjacent to the long span. Key words: dynamic, seismic, response, highway, bridges, earthquake, base isolation, design.
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HUSAIN, D., A. QURAISHI, and A. ALIBRAHIM. "Local Scour at Bridge Abutments." Journal of King Abdulaziz University-Engineering Sciences 10, no. 1 (1998): 141–53. http://dx.doi.org/10.4197/eng.10-1.10.
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Noè Gorini, Davide, Luigi Callisto, and Andrew J. Whittle. "Dominant responses of bridge abutments." Soil Dynamics and Earthquake Engineering 148 (September 2021): 106723. http://dx.doi.org/10.1016/j.soildyn.2021.106723.
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Melville, B. W. "Local Scour at Bridge Abutments." Journal of Hydraulic Engineering 118, no. 4 (April 1992): 615–31. http://dx.doi.org/10.1061/(asce)0733-9429(1992)118:4(615).
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Muzzammil, Mohammad. "ANFIS approach to the scour depth prediction at a bridge abutment." Journal of Hydroinformatics 12, no. 4 (March 26, 2010): 474–85. http://dx.doi.org/10.2166/hydro.2010.004.
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An accurate estimation of the maximum possible scour depth at bridge abutments is of paramount importance in decision-making for the safe abutment foundation depth and also for the degree of scour counter-measure to be implemented against excessive scouring. Despite analysis of innumerable prototype and hydraulic model studies in the past, the scour depth prediction at the bridge abutments has remained inconclusive. This paper presents an alternative to the conventional regression model (RM) in the form of an adaptive network-based fuzzy inference system (ANFIS) modelling. The performance of ANFIS over RM and artificial neural networks (ANNs) is assessed here. It was found that the ANFIS model performed best among of these methods. The causative variables in raw form result in a more accurate prediction of the scour depth than that of their grouped form.
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Matia, Santu, and Diptesh Das. "Non-Linear Visco-elastic Pounding in Multi-span Simply Supported Isolated Bridges." Proceedings of the 12th Structural Engineering Convention, SEC 2022: Themes 1-2 1, no. 1 (December 19, 2022): 529–36. http://dx.doi.org/10.38208/acp.v1.544.
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The pounding phenomena in multi-span, simply supported, isolated bridges under earthquake ground motion is investigated. The piers are considered as elastic members and the abutments as rigid ones. An isolated bridge, taken from literature, is modeled as a multi-degree of freedom system by using Matlab program and Simulink. State-of-the-art reveals that study on non-linear visco-elastic pounding in seismically isolated, simply supported bridges is limited. The present paper explores this problem of pounding in bridges by considering the bearing isolations. Results show that pounding occurs more prominently at the locations where there are changes in structural properties such as the changes in height of pier or the presence of abutment.
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Hruštinec, Luboš. "ANALYSIS OF THE TIME COURSE OF A BRIDGE ABUTMENTS SETTLEMENT." Acta Polytechnica CTU Proceedings 16 (June 19, 2018): 11. http://dx.doi.org/10.14311/app.2018.16.0011.
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The paper deals with the time course of the bridge abutments settlement (consolidation of the subsoil) on the motorway D4 in Stupava, Slovakia. The bridge abutments are founded on an earth embankment 5.5 meters in height and a group of piles. Over 6 years of geotechnical monitoring after the construction of bridge abutments, there were measured settlements from 102 to 106 mm. The measured settlement of intermediate bridge piers was only up to 16 mm. Geotechnical calculations and analysis are focused on the comparison of the final settlements prognosis and its time course with the real measured values.
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Shahsavari, Hamed, Manouchehr Heidarpour, and Mohammad Mohammadalizadeh. "Simultaneous Effect of Collar and Roughness on Reducing and Controlling the Local Scour around Bridge Abutment." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 65, no. 2 (2017): 491–99. http://dx.doi.org/10.11118/actaun201765020491.
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Investigation of local scour around hydraulic structures particularly bridges is of crucial importance in river engineering. Bridge destruction mostly occurs as a result of scour phenomenon around piers and abutments, not because of structural weaknesses. Hence, finding a solution to reduce scour depth is momentous. In this study which was conducted in the conditions of clear water scour, the effect of local roughness and collar and also impact of using them simultaneously around bridge abutment were evaluated. The results demonstrated that the existence of roughness causes a reduction in the severity of scouring process and its final depth and the use of collar leads to a delay in the scouring process in addition to the ultimate reduction in the scour depth, which in case of using them simultaneously, scour depth decreases by about 83%.
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Huang, Jian Wei, and Jonathan Davis. "Skew Reduction Factors for Moment in NEXT Beam Bridges with Integral Abutments." Applied Mechanics and Materials 878 (February 2018): 49–53. http://dx.doi.org/10.4028/www.scientific.net/amm.878.49.
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Northeast Extreme Tee (NEXT) beams have been recently developed for the accelerated bridge construction. The skew effect on live load distribution in a NEXT beam bridge, especially with integral abutments, is not clear and shall be assessed. In this paper, various skew NEXT beam bridges are evaluated through validated finite element (FE) analyses with solid brick elements. Parameters as studied include beam section, span length, and skew angle. Per AASHTO LRFD specifications, one- and two-lane loaded cases are examined to obtain the maximum tensile strains in beam stems under the design live loading (HL-93). Unskewed bridges are used as control specimens to compute skew reduction factors (SRF) for moment from the obtained FE strains. The FE- and LRFD-SRFs for moment are compared in terms of figures, which indicate the LRFD-SRFs have good agreements with the FE-SRFs at large. For the majority of the bridges, LRFD-SFRs govern the FE-SRFs. The research findings from this paper are useful for practicing engineers to safely design a skew NEXT beam bridge with integral abutments.
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KORI, JAGADISH G., and R. S. JANGID. "SEMIACTIVE CONTROL OF SEISMICALLY ISOLATED BRIDGES." International Journal of Structural Stability and Dynamics 08, no. 04 (December 2008): 547–68. http://dx.doi.org/10.1142/s021945540800279x.
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This paper describes the application of semiactive devices for controlling the earthquake response of two highway bridges of different cross sections and pier heights. Each of the bridges consists of a three-span continuous deck supported on the piers and abutments. Semiactive devices such as the magnetorheological damper, the variable friction damper and the variable stiffness device are considered as the control devices. These devices are inserted between the deck and piers or abutments of the isolated bridge. The semiactive device changes its properties according to the structural response and adds control forces to the system. Each pier supporting the bridge is modeled as a linear lumped mass system. The optimum parametric values of the semiactive dampers are evaluated and considered in analysis of the bridge. A comparative study is performed for different semi-active devices installed on the bridges under different seismic loadings in the longitudinal direction. The behaviors of the bridges with different semiactive isolation devices are compared with the corresponding nonisolated ones. The semiactive dampers are observed as an effective protective device in reducing the displacements of the isolation bridges as well as the base shear of the piers.
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Sadek, Sherif A., and Dina Elawady. "Impact of Removable Partial Denture Type on Patient Satisfaction and Abutment Survival Rate-RCT." Open Access Macedonian Journal of Medical Sciences 7, no. 15 (August 14, 2019): 2513–19. http://dx.doi.org/10.3889/oamjms.2019.668.
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BACKGROUND: Patient’s satisfaction and the preservation of abutments is the most important outcomes that the clinician seeks during fabrication of any dental treatment, especially when it is concerned with removable prosthodontic rehabilitation.
AIM: The present study evaluates three different Removable Partial Denture (RPD) types restoring mandibular class II modification I edentulous cases with regards to patient’s satisfaction and abutments survival.
METHODS: Forty-two partially edentulous patients were divided into three groups (Group I rehabilitated with Vitallium RPD, Group II rehabilitated with Vitallium RPD where the modification area restored with the surveyed bridge, Group III rehabilitated with Thermopress RPD). The patients were followed up for twenty-four months. Using a questionnaire, prosthodontic maintenance required was documented at the delivery and after 3 months.
RESULTS: There was a significant difference regarding patient satisfaction for group III (P-value <0.05) while for groups I and II there was a non-significant difference (P-value >0.05). Regarding the survival rate, there was a non-significant difference between the three groups (P-value >0.05) at the end of twenty-four months of follow up.
CONCLUSION: Patient satisfaction and abutment survival were better with Thermopress RPD than conventional Vitallium RPD or Vitallium RPD with a surveyed bridge restoring the modification area. Although a non-statistically significant difference was found in the survival rate of abutments between groups, a clinically important result was revealed as no abutments failures were reported in the Thermopress group.
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Gorini, Davide Noè, Andrew John Whittle, and Luigi Callisto. "Ultimate Limit States of Bridge Abutments." Journal of Geotechnical and Geoenvironmental Engineering 146, no. 7 (July 2020): 04020054. http://dx.doi.org/10.1061/(asce)gt.1943-5606.0002283.
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Najafzadeh, Mohammad, Gholam-Abbas Barani, and Masoud Reza Hessami Kermani. "Abutment scour in clear-water and live-bed conditions by GMDH network." Water Science and Technology 67, no. 5 (March 1, 2013): 1121–28. http://dx.doi.org/10.2166/wst.2013.670.
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In the present study, the Group Method of Data Handling (GMDH) network has been utilized to predict abutments scour depth for both clear-water and live-bed conditions. The GMDH network was developed using a Back Propagation algorithm (BP). Input parameters that were considered as effective variables on abutment scour depth included properties of sediment size, geometry of bridge abutments, and properties of approaching flow. Training and testing performances of the GMDH network were carried out using dimensionless parameters that were collected from the literature. The testing results were compared with those obtained using the Support Vector Machines (SVM) model and the traditional equations. The GMDH network predicted the abutment scour depth with lower error (RMSE (root mean square error) = 0.29 and MAPE (mean absolute percentage of error) = 0.99) and higher (R = 0.98) accuracy than those performed using the SVM model and the traditional equations.
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Forcellini, Davide. "Assessment of the Seismic Vulnerability of Bridge Abutments with 3D Numerical Simulations." Geosciences 12, no. 9 (August 25, 2022): 316. http://dx.doi.org/10.3390/geosciences12090316.
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The role of abutments on the seismic vulnerability of bridges has been relatively little studied in geotechnical literature. To cover this gap, 3D numerical simulations were herein performed, by studying the seismic performance of three single-span bridge configurations. The numerical models used OpenSees to account the effects due to soil structure interaction between the deck and the abutments. In particular, advanced materials were implemented to model the non-linear hysteresis and plasticity that are responsible for soil deformations and, thus, structural damage. A probabilistic-based approach was considered and analytical fragility curves were developed to account modeling uncertainties. The role of bridge deformability was investigated by considering several limit states based on the calculation of the longitudinal displacements of the deck.
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Bois, Axel-Pierre, Mohamed Lachemi, and Gérard Ballivy. "Auscultation d'une culée du pont de Portneuf à l'aide d'une inclusion de béton instrumentée (CIUS)." Canadian Journal of Civil Engineering 23, no. 5 (October 1, 1996): 1129–36. http://dx.doi.org/10.1139/l96-920.
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The Portneuf Bridge, built in 1992, is the first air-entrained high-performance concrete bridge in North America. To understand its short and long term behaviour, an auscultation program has been set. Hence, a cylindrical concrete inclusion of the Université de Sherbrooke was installed in one of the abutments of the bridge. The aim of this study is to present the first results thus acquired. The analysis of the results allowed to calculate the coefficient of thermal expansion of the concrete and to assess deformation variations due to shrinkage and creep and the effects of rebar–concrete interaction in the upper abutment region. Moreover, the presence of thermal gradients, which creates nonisotropic deformations, has been established. Key words: high-performance concrete, deformations, thermal gradients, instrumentation, bridge, monitoring. [Journal translation]
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Bukowski, M., P. Łysiak, R. Oleszek, and W. Trochymiak. "Modeling and Analysis of Ground Settlement Between a Flyover and Reinforced Soil Embankment." Archives of Civil Engineering 64, no. 4 (December 1, 2018): 77–100. http://dx.doi.org/10.2478/ace-2018-0064.
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AbstractDevelopment of the transport infrastructure in Poland has contributed to the implementation of various technologies of construction of bridges and their components. Use of reinforced soil for construction of embankments, retaining structures (RSS walls) and abutments is one of the solutions which has been frequently used for the past twenty years. Shortly after its development, the technology proposed by Henri Vidal in 1966 also gained appreciation in Poland [4]. Reinforced soil bridge abutments started to be widely used in Poland at the turn of the 20th century. The bridge facilities at the junction of Trasa Siekierkowska route and Wał Miedzeszyński Street in Warsaw, which were built in the years 2000÷2002, are an example of structures from that period. The authors of this paper have been particularly interested in the outermost supports of the reinforced concrete flyovers which were constructed in the form of intermediate reinforced soil abutments. Offsets – the vertical displacements, in the range of 15÷25mm, emerging between the level of the road surface and the steel elements of the expansion joints which separate the flyover’s structure from the embankment – were observed in 2015, in the course of regular inspections. While accounting for the observations which have been made, the surveying measurements and the ground investigation, the paper diagnoses and describes the mechanism which led to the emergence of the offsets. Potential patterns of the occurrence of additional settlements, as the reason for emergence of the offsets, were identified and analyzed. The settlement of the outermost support (abutment), as a result of increase of relative density of alluvial sands due to the dynamic interaction of the roadways of Wał Miedzeszyński Street, was analyzed. Analytical and numeric approaches were used in the course of analysis while relying on PLAXIS and MIDAS software.
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Raikar, Rajkumar V., Jian-Hao Hong, Anandrao R. Deshmukh, and Wen-Dar Guo. "Parametric Study on Abutment Scour under Unsteady Flow." Water 14, no. 11 (June 6, 2022): 1820. http://dx.doi.org/10.3390/w14111820.
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Experimental results on scour at abutments under unsteady clear water flow condition are presented. Three shapes of short abutments (abutment length/upstream flow depth < 1) were tested, namely, rectangular/vertical wall, semi-circular, and trapezoidal/45° wing-wall abutments embedded in uniform sands of two sizes having d50 = 0.52 mm and 0.712 mm. The unsteadiness of the flow is considered in the form flood hydrographs of three forms, namely: advanced flood hydrograph (Type I), symmetrical flood hydrograph (Type II), and delayed flood hydrograph (Type III) with the flow maintained at clear water condition in all cases. The experimental findings are used to represent the influence of various parameters on scour depth at bridge abutments. It was observed that the scour depth at rectangular abutments is greater than that at trapezoidal and semi-circular abutments. The scour depths at abutments embedded in finer sediments are greater than those in coarser sediments. In addition, based on the study of effect of three flood hydrographs, it was noticed that the delayed flood hydrograph yields greater scour depth as compared to the other two cases. Further, based on the method of superposition and the correction of shape factor, a semi-empirical model using dimensionless parameters is proposed to compute the temporal evolution of scour depth at abutments under unsteady clear water conditions. The parameters used in this model include flow shallowness, flow intensity, sediment coarseness, and time factor. It was found that the proposed model corresponds well with the data of time-dependent scour depth in uniform sediments obtained from the present experiments (unsteady flows) and reported by different investigators (steady flows).