设计地震下铁路简支梁桥支座水平地震力计算方法研究  

Calculation methods for horizontal seismic force of the bearing of a railway simply-supported girder bridge under design ground motions

作　　者：王春阳 刘正楠[1] 张永亮[1] 李晓钟[1] WANG Chunyang;LIU Zhengnan;ZHANG Yongliang;LI Xiaozhong(College of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730070, Gansu, China)

机构地区：[1]兰州交通大学土木工程学院,甘肃兰州730070

出　　处：《地震工程学报》2022年第2期270-275,284,共7页China Earthquake Engineering Journal

基　　金：国家自然科学基金(52168018,52162043)。

摘　　要：为研究设计地震作用下铁路梁桥支座水平地震力按静力法计算的准确性和适用性,以一墩高为5~20 m、跨径为32 m的简支梁桥圆端形重力式桥墩为研究对象,建立单墩抗震模型,采用反应谱法分析不同场地条件下支座的水平地震力,探讨设计地震作用下桥墩截面的合理刚度取值。分析结果表明设计地震下桥墩均处于开裂状态,应以开裂截面刚度作为反应谱计算的截面刚度;静力法计算支座水平地震力会造成设计值偏大或偏小;桥墩越矮,场地条件越差,动力效应越明显,建议支座水平地震力采用动力法进行分析。The accuracy and applicability of horizontal seismic force of the railway girder bridge’s bearings under design earthquakes,which was calculated with the static method,were studied in this paper.The round-ended gravity piers of a railway simply-supported girder bridge with a pier height of 5-20 m and a span of 32 m was taken to established a single pier seismic model.The response spectrum method was used to analyze the horizontal seismic force of the bearings under different site conditions,and the reasonable stiffness value of pier section under design earthquake was discussed.The analysis results showed that the piers are cracked under design earthquake,so the stiffness of cracking section should be selected as the section stiffness when calculating with the response spectrum method.The design value will be too large or too small if using the static method to calculate the horizontal seismic force of bearing.With the decreasing height of pier,the site conditions become worse and the dynamic effect become more obvious.It is suggested that the horizontal seismic force of the bearing should be calculated by the dynamic method.

关 键 词：铁路简支梁桥 支座水平地震力 设计地震 静力法 反应谱法 

分 类 号：U24[交通运输工程—道路与铁道工程]