墩底设置无黏结钢筋的铁路重力式桥墩在静力作用下的抗震性能分析  

Seismic performance analysis of railway gravity piers with unbonded reinforcement at the bottom of piers under static load

作　　者：鲁锦华 陈兴冲[1] 丁明波[1] 马华军[1] LU Jinhua;CHEN Xingchong;DING Mingbo;MA Huajun(School of Civil Engineering Lanzhou Jiaotong University,730070 Lanzhou,China)

机构地区：[1]兰州交通大学土木工程学院,兰州730070

出　　处：《应用力学学报》2023年第5期1078-1084,共7页Chinese Journal of Applied Mechanics

基　　金：国家自然科学基金资助项目(No.51768036,51968039);甘肃省教育科技创新基金项目(No.2022A-033)。

摘　　要：为了提高铁路重力式桥墩的延性性能,提出了在墩底局部设置无黏结钢筋的设计方法。设计5个不同无黏结钢筋类型的桥墩,采用数值分析方法研究无黏结钢筋数量及无黏结高度对桥墩抗震性能的影响。研究结果表明:墩底设置无黏结钢筋可有效改善铁路重力式桥墩的延性性能,且对桥墩的承载能力和刚度影响较小,但是会增加桥墩滞回曲线形状的“捏缩”效应;无黏结钢筋比例越大,桥墩的延性性能越好,钢筋无黏结高度在一定范围内对桥墩延性性能的影响较大;数值分析验证了在墩底布置无黏结钢筋的方法提高延性抗震性能的可行性。本研究成果可应用于铁路重力式桥墩抗震设计研究领域。In order to improve the ductility performance of railway gravity piers,the design method of local unbonded reinforcement at the bottom of piers is proposed.Five piers with different types of unbonded steel bars are designed.Numerical analysis is used to study the influence of the amount and height of unbonded reinforcement on the seismic performance of railway gravity piers.It is found that the unbonded reinforcement at the bottom of the pier can effectively improve the ductility performance of the railway gravity pier,and it has little influence on the bearing capacity and stiffness of the pier,but it will increase the“pin-ching”effect of the shape of the hysteresis curve of the pier.The ductility performance of piers gets better with the increase of the amount of unbonded reinforcement.The unbonded height of reinforcement has a great influence on the ductility of pier in a certain range.The feasibility of improving ductile seismic performance by installing unbonded reinforcement at the bottom of pier is verified by numerical analysis.The research results can be applied in the research field of seismic design of railway gravity piers.

关 键 词：无黏结钢筋 铁路重力式桥墩 数值分析 抗震性能 延性性能 

分 类 号：U24[交通运输工程—道路与铁道工程]