铁路简支梁桥墩抗震简化算法与有限元法对比研究  

Comparative Study on Seismic Simplified Algorithm and Finite Element Method for Simply Supported Girder Bridge Pier Railway

作　　者：李晓波 LI Xiaobo(China Railway Design Corporation,Tianjin 300308,China)

机构地区：[1]中国铁路设计集团有限公司,天津300308

出　　处：《铁道标准设计》2021年第8期77-82,共6页Railway Standard Design

基　　金：中国铁路设计集团有限公司科技开发课题(2020YY340641)。

摘　　要：为了明确铁路简支梁桥墩抗震简化算法与全桥有限元法结果的差异,以铁路常用标准32 m跨度简支箱梁为研究对象,在纵、横向多遇地震输入下,研究不同墩高、场地类别、基础刚度下简化算法与有限元法计算差值的规律,分析造成两种方法误差的原因。结果表明:简支梁桥墩抗震简化算法在纵向的适用性要优于横向,但纵、横向均有有限元法结果大于简化算法结果的情况,纵向主要是受场地周期的影响,而横向主要是高阶振型的影响;当场地条件较好时,可以直接采用简化算法结果设计桥墩,当场地条件较差且基础刚度较大时,为保证结构安全,桥墩简化算法结果应在纵、横向分别考虑1.1、1.2的安全系数。In order to clarify the differenced between the seismic simplified algorithm and the finite element method of railway simply supported girder pier,the railway standard of 32 m span simply supported box beam is taken as the research object.With the input of longitudinal and transverse earthquakes,the law of calculation differenced between the simplified algorithm and the finite element method under different pier height,site classification and foundation stiffness are studied,and causes of the errors of the two methods are analyzed.The results show that the applicability of seismic simplified algorithm in longitudinal direction is better than that in transverse direction,but there are the cases that the results of finite element method are larger than that of simplified ones in both directions.The longitudinal is mainly affected by site cycle,while the transverse is mainly influenced by higher modes of vibration.When site conditions are good,the simplified algorithm can be directly used to design piers.When the site conditions are poor and the foundation stiffness is large,the application of the simplified algorithm should consider the safety factors of 1.1 and 1.2 in the longitudinal and transverse directions respectively in order to ensure structural safety.

关 键 词：铁路桥 简支箱梁 桥墩 抗震计算 简化算法 有限元法 场地类别 

分 类 号：U442.55[建筑科学—桥梁与隧道工程] U448.217[交通运输工程—道路与铁道工程]