Bridge Structures最新文献_第3页

Design Optimization of PCI Girders: A Parametric Study PCI梁的优化设计:参数化研究

IF 0.6

Bridge Structures Pub Date : 2023-01-06 DOI: 10.3233/brs-220203

M. Jahjouh, S. Erhan

{"title":"Design Optimization of PCI Girders: A Parametric Study","authors":"M. Jahjouh, S. Erhan","doi":"10.3233/brs-220203","DOIUrl":"https://doi.org/10.3233/brs-220203","url":null,"abstract":" This study investigates the effect of superstructure configuration on the optimum design of slab on Precast I (PCI) girder bridges. For this purpose, more than 20,000 bridge cases of varying superstructure configurations are considered to investigate the effects of various superstructure parameters such as girder spacing, span length, slab thickness and girder types on the optimum design of slab on PCI girder bridges. PCI girders are designed conforming to the AASHTO LRFD for flexure using stress limits at the service limit state, then checked at ultimate for flexure and shear using factored loads at the strength limit state. A modified harmony search optimization algorithm is used to obtain optimum bridge design parameters using standard AASHTO PCI girders according to these AASHTO LRFD requirements. Those girders are designed taking into consideration geometrical constraints, stress constraints and constraints related to the conformity of the design with the AASHTO LRFD code. Various sensitivity analysis are performed to investigate the effect of different geometrical factors on the design of the girders, and easy-to-use design aids were developed. The outcomes of this study may facilitate the bridge engineers to choose optimum design parameters such as girder types and spacing as well as number strands for a certain span length before the design of slab on PCI girder bridges.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42721072","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Evaluation of hybrid NSM-CFRP technical bars and FRP sheets for seismic rehabilitation of a concrete bridge pier NSM-CFRP技术钢筋和FRP片材在混凝土桥墩抗震加固中的应用评价

IF 0.6

Bridge Structures Pub Date : 2023-01-06 DOI: 10.3233/brs-290180

Mohamad R. Shokrzadeh, F. Nateghi-Alahi

{"title":"Evaluation of hybrid NSM-CFRP technical bars and FRP sheets for seismic rehabilitation of a concrete bridge pier","authors":"Mohamad R. Shokrzadeh, F. Nateghi-Alahi","doi":"10.3233/brs-290180","DOIUrl":"https://doi.org/10.3233/brs-290180","url":null,"abstract":"Seismic retrofit is a cost-effective and sustainable solution for improving bridge structures in seismic zones. Fiber Reinforced Polymer (FRP) is commonly used to replace steel components in retrofit projects due to their light weight, high strength, and high corrosion resistance. The fabrication of novel hybrid structures from FRP and concrete is the next step researchers are addressing. In this context, the present study focuses on numerical modeling of the experimentally determined response of a hybrid FRP and concrete bridge pier subjected to quasi-static tests. The results from FEM showed strong agreement with the experimental response in terms of load-displacement curve and failure mode. After validating the model, alternative designs (changing the height of the CFRP slab, changing the height and compaction of the CFRP bar, and concrete encasement with and without CFRP slab) were numerically tested to investigate the effects of each model on the load capacity. With the conventional concrete encasement, the bearing capacity of the bridge pier can be rehabilitated, but with the CFRP plate in the above system, the bearing capacity of the bridge pier is increased by more than 60%. Therefore, it can be concluded that seismic strengthening techniques with CFRP sheets and mounted NSM-CFRP bars are suitable for concrete bridge piers.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2023-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48939721","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

An overview of integral abutments: Current practices, field monitoring and deck replacement measures 整体式桥台概述：当前做法、现场监测和桥面更换措施

IF 0.6

Bridge Structures Pub Date : 2022-09-28 DOI: 10.3233/brs-220196

R. Vasconez, Aliaksei Kustau, H. Najm

{"title":"An overview of integral abutments: Current practices, field monitoring and deck replacement measures","authors":"R. Vasconez, Aliaksei Kustau, H. Najm","doi":"10.3233/brs-220196","DOIUrl":"https://doi.org/10.3233/brs-220196","url":null,"abstract":"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.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48137357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Editorial Issue 18(1-2) 第十八期社论(1-2)

IF 0.6

Bridge Structures Pub Date : 2022-09-28 DOI: 10.3233/brs-220199

K. Mahmoud

引用次数: 0

Model calibration of a long-span concrete cable-stayed bridge based on structural health monitoring data: Influence of concrete variability 基于结构健康监测数据的大跨度混凝土斜拉桥模型标定:混凝土变异性的影响

IF 0.6

Bridge Structures Pub Date : 2022-09-28 DOI: 10.3233/brs-220195

Cortney Natalicchio, H. Al-Khateeb, M. Chajes, Z. Wu, Harry W. Shenton III

{"title":"Model calibration of a long-span concrete cable-stayed bridge based on structural health monitoring data: Influence of concrete variability","authors":"Cortney Natalicchio, H. Al-Khateeb, M. Chajes, Z. Wu, Harry W. Shenton III","doi":"10.3233/brs-220195","DOIUrl":"https://doi.org/10.3233/brs-220195","url":null,"abstract":"Structural Health Monitoring (SHM) systems, in combination with controlled load tests, can provide valuable data for calibrating high fidelity bridge models, which can then be used for evaluating the long-term performance of the bridge, improved load ratings, and permit vehicle evaluation. The objective of this research was to calibrate a 3D model of the Indian River Inlet (IRIB) cable-stayed bridge, using strains recorded by the bridge SHM system during a controlled load test. The bridge was modeled in STAAD-Pro and calibrated using a pre-commercialized software platform that uses a Generic Algorithm to minimize the error between the measured and predicted strains. The calibration parameters were the elastic modulus of groups of the main longitudinal edge girder/deck elements, which once calibrated, could be related to the measured concrete strength of the members. Four different models were investigated, using 6, 10, 14, and 18 parameter element groups of the edge girder members. Of the different models, the 14 and 18 parameter models yielded the best results. The “design” model yielded errors as high as 42% when compared to the measured strains; the error was less than 10% for the majority of measurements for the 14-parameter model. Including the effect of the traffic barriers in the model, the weighted average concrete strength of the calibrated model was within 4% of the measured weighted strength. The calibration was shown to be insensitive to measurement noise and was validated using several unique single and multi-vehicle load cases that were heavier and more offset from the centerline of the bridge. The calibration procedure was able to capture the variability in flexural stiffness of the edge girders due to the variability of the concrete, resulting in significantly better agreement between the live load measured strains and the model predicted strains.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48124065","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Shear design of precast prestressed concrete NEXT beam bridges: A critical assessment 预制预应力混凝土NEXT梁桥的剪切设计:关键评估

IF 0.6

Bridge Structures Pub Date : 2022-09-28 DOI: 10.3233/brs-220198

Jianwei Huang

{"title":"Shear design of precast prestressed concrete NEXT beam bridges: A critical assessment","authors":"Jianwei Huang","doi":"10.3233/brs-220198","DOIUrl":"https://doi.org/10.3233/brs-220198","url":null,"abstract":"Northeast extreme tee (NEXT) precast prestressed concrete beams have recently emerged as a promising solution to accelerate bridge construction and enhance the sustainability of bridges. To date, several studies on the live load distribution factor (LLDF) for moment and shear in NEXT F beam bridges have been reported, which indicated that using the AASHTO LRFD LLDF for moment in NEXT F beam bridges could provide a sufficient safety margin; however, a 20% increase in the LRFD LLDF for shear was recommended for the safety of shear design. This paper intended to investigate the required transverse shear reinforcements in NEXT F beam bridges by using a factor of 1.2 for the LRFD LLDF for shear. A comprehensive study was carried out by considering various parameters, including concrete strength, beam section, bridge section, and span length. Results from this study showed that providing the minimum transverse shear reinforcement could offer a sufficient safety margin for the shear design of NEXT F beam bridges, even with an increase of 20% on the LRFD LLDF for shear. It is recommended that a factor of 1.2 be used for the LRFD LLDF for shear to ensure a safe design of NEXT F beam bridges, though the minimum transverse reinforcements will be likely to control the shear design.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2022-09-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46224069","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Stress change calculations in accidentally damaged prestressed bridge girders 意外损伤预应力桥梁主梁应力变化计算

IF 0.6

Bridge Structures Pub Date : 2022-09-28 DOI: 10.3233/brs-220197

H. Tabatabai, A. Nabizadeh

引用次数: 0

Dynamic amplification factors of girder and cables of extradosed bridges during sudden cable failure 拉索突然失效时矮塔主梁和拉索的动力放大系数

IF 0.6

Bridge Structures Pub Date : 2021-12-09 DOI: 10.3233/brs-210189

Homer Buelvas, J. Benjumea, Gustavo Chio

{"title":"Dynamic amplification factors of girder and cables of extradosed bridges during sudden cable failure","authors":"Homer Buelvas, J. Benjumea, Gustavo Chio","doi":"10.3233/brs-210189","DOIUrl":"https://doi.org/10.3233/brs-210189","url":null,"abstract":"The rupture of a cable in cable-supported bridges is an accidental condition that should be considered during the design phase due the impact that this situation could have on the structural safety of the bridge and users. For that reason, design guidelines suggest carrying out a pseudo-static analysis where the failing cable is replaced by a load of the same magnitude as the pre-rupture tension but applied in the opposite direction and multiplied by a dynamic amplification factor (DAF) between 1.5 and 2.0. Previous studies in cable-stayed bridges have shown that the pseudo-static approach may not be suitable. Due to the wide use of extradosed bridges in infrastructure projects around the world, a computational analysis was performed in this investigation to estimate the dynamic amplification factors of extradosed bridge girders and cables when sudden failure of an extradosed cable occurs. The main goal of the study is to determine whether the pseudo-static approach suggested in the guidelines is acceptable. Linear response history analyses were performed by using computational models of extradosed bridges in which the girder stiffness and the suspension (lateral or central) and cable layout (fan or harp) of the cables were modified. From the analysis, the DAFs were calculated and compared to those recommended in the design guidelines. The calculated DAFs for the axial forces and bending moment in the girder of the bridges and for the axial forces in the extradosed cables were smaller than 2.0. However, in some cases the DAF for shear forces were higher than 2.0, especially when the girder stiffness was relatively low. The results indicate that the recommendations of the design guidelines are adequate for extradosed bridges, which is a result of the relatively high stiffness of the girder and low inclination of extradosed cables. Despite this, response history analyses like the one performed in this study are recommended to assess the response of the bridge under cable breakage.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47152976","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparison of eigenanalysis and Ritz vector approaches for response spectrum analysis of soil-pile-bridge systems 土-桩-桥体系响应谱分析的特征分析法与Ritz向量法比较

IF 0.6

Bridge Structures Pub Date : 2021-12-09 DOI: 10.3233/brs-210192

M. Davidson, A. Patil, S. A. Rosenfeld, Z. Zhu

{"title":"Comparison of eigenanalysis and Ritz vector approaches for response spectrum analysis of soil-pile-bridge systems","authors":"M. Davidson, A. Patil, S. A. Rosenfeld, Z. Zhu","doi":"10.3233/brs-210192","DOIUrl":"https://doi.org/10.3233/brs-210192","url":null,"abstract":"Frequency-based analysis techniques such as response spectrum analysis (RSA) are widely used for designing bridges in seismically active regions. Two well-known analysis procedures that underlie RSA are the solution of the eigenproblem and the approximation of the solution to the eigenproblem (i.e., approximation of eigenvectors and eigenvalues) through use of force-dependent Ritz vectors. While frequency-based methods have achieved widespread adoption in practice, certain simplifications remain common, such as neglecting soil-structure interaction (SSI) due to a fixed-base assumption. In the present study, frequency-based techniques packaged within a research version of a design-oriented computational tool are employed to analyze, assess, and compare results obtained from RSA with use of the eigenanalysis, and separately, Ritz vector approaches. Importantly, for the bridge configurations analyzed, SSI is taken into account. As outcomes, the potential benefits of the Ritz vector approach (as well as modeling strategies) are demonstrated. The study outcomes are intended to aid practicing engineers when the need to account for SSI is recognized as pertinent to a given bridge seismic design application.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42450730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Shear live load analysis of NEXT beam bridges for accelerated bridge construction NEXT梁桥加速施工的剪切活载分析

IF 0.6

Bridge Structures Pub Date : 2021-12-09 DOI: 10.3233/brs-210191

Jianwei Huang

{"title":"Shear live load analysis of NEXT beam bridges for accelerated bridge construction","authors":"Jianwei Huang","doi":"10.3233/brs-210191","DOIUrl":"https://doi.org/10.3233/brs-210191","url":null,"abstract":"Using precast concrete elements in bridge structures has emerged as an economic and durable solution to enhance the sustainability of bridges. The northeast extreme tee (NEXT) beams were recently developed for accelerated bridge construction by the Precast/Prestressed Concrete Institute (PCI). To date, several studies on the live load distribution factor (LLDF) for moment in NEXT F beam bridges have been reported. However, the LLDFs for shear in NEXT F beam bridges are still unclear. In this paper, the lateral distributions of live load shear in NEXT F beam bridges were examined through a comprehensive parametric study. The parameters covered in this study included bridge section, span length, beam section, number of beams, and number of lanes loaded. A validated finite element (FE) modeling technique was employed to analyze the shear behavior of NEXT F beam bridges under the AASHTO HL-93 loading and to determine the LLDFs for shear in NEXT beam bridges. A method for computing the FE-LLDF for shear was proposed for NEXT beam bridges. Results from this study showed that the FE-LLDFs have a similar trend as the AASHTO LFRD-LLDFs. However, it was observed that some LRFD-LLDFs are lower than the FE-LLDFs by up to 14.1%, which implied using the LRFD-LLDFs for shear could result in an unsafe shear design for NEXT beam bridges. It is recommended that a factor of 1.2 be applied to the LRFD-LLDF for shear in NEXT F beam bridges for structural safety and design simplicity.","PeriodicalId":43279,"journal":{"name":"Bridge Structures","volume":null,"pages":null},"PeriodicalIF":0.6,"publicationDate":"2021-12-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48161320","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1