地震作用下铁路桥墩设计参数对抗剪性能的影响  

Study on Influence of Design Parameters of Railway Piers on Shear Performance under Earthquake

作　　者：许敏[1] 陈克坚[1] 罗立洋 程志宝[2] XU Min;CHEN Kejian;LUO Liyang;CHENG Zhibao(China Railway Eryuan Engineering Group Co.,Ltd.,Chengdu 610031,China;Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031 [2]北京交通大学,北京100044

出　　处：《高速铁路技术》2020年第1期41-46,共6页High Speed Railway Technology

摘　　要：为研究地震作用下铁路桥墩设计参数对抗剪性能的影响,本文建立了用于钢筋混凝土桥墩抗剪性能分析的有限元模型,通过与桥墩拟静力试验结果的对比,验证了该有限元模型的准确性和可靠性。并基于所建立的有限元模型,计算研究了轴压比、剪跨比、纵筋率、宽高比等参数对铁路桥墩抗剪性能的影响规律。研究结果表明:(1)轴压比的增加会使混凝土桥墩的极限抗剪承载力提高,但会降低位移延性系数;(2)剪跨比的增加会降低桥墩的极限抗剪承载力,但随着剪跨比的增大,抗弯开始趋于控制桥墩设计;(3)宽高比对桥墩的抗剪性能影响不大;(4)提高纵筋率并不能显著提高桥墩的抗剪能力,同时有可能导致位移延性系数的降低,因此在桥墩抗震设计时,不宜盲目的提高纵筋率,应综合考虑桥墩强度和延性要求合理确定。In order to study the influence of the design parameters of railway piers on the shear performance under earthquake,a finite element model is established for the shear performance analysis of the reinforced concrete piers and the accuracy and reliability of this finite element model are verified by comparison with the results of the quasi-static test of piers in the paper.Based on the finite element model established in this paper,the influence of such parameters as axial compression ratio,shear span ratio,longitudinal reinforcement ratio and ratio of width to height on the shear performance of reinforced concrete bridge piers is studied.The results show that(1)the increase of axial compression ratio will increase the ultimate shear capacity of concrete piers,but reduce the displacement ductility coefficient;(2)the increase of shear span ratio will reduce the ultimate shear capacity of piers,but with the increase of shear span ratio,the bending resistance tends to control the piers design;(3)the ratio of width to height has little influence on the shear performance of piers;(4)the increase of the longitudinal reinforcement rate does not significantly improve the shear capacity of piers,and may result in the reduction of the displacement ductility coefficient,therefore,in the seismic design of the pier,it is not suitable to blindly increase the longitudinal reinforcement rate.The longitudinal reinforcement rate of the pier should be reasonably determined by considering the strength and ductility requirements of piers.

关 键 词：抗剪性能 有限元 抗剪承载力 位移延性 

分 类 号：U441.5[建筑科学—桥梁与隧道工程]