铁道科学与工程学报2025，Vol.22Issue(2)：712-722,11.DOI:10.19713/j.cnki.43-1423/u.T20240565
铁路桥梁典型减隔震设计显式计算方法
Explicit analytical method for typical isolated system of railway bridges
摘要
Abstract
The isolation system in combination with displacement-dependent friction pendulum bearings(FPBs)and mild steel dampers is widely utilized for railway bridges in high seismic zones.However,using nonlinear time history analysis for the seismic design is very complicated and time-consuming,and the equivalent linear analytical method that has been proposed in many native and abroad seismic design codes and specifications is an implicit process and requires iterative analyses.An alternative explicit analytical method with high estimation precision was presented based on the equivalent linear analytical method and the structural characteristics of railway bridges.A comprehensive sampling analysis with variation for all design parameters of the isolation system was carried out for error analysis of the presented explicit analytical method.The results show that the seismic response of the bearing of the combined isolation system can be well expressed as a power function of the spectrum acceleration at 1 second.Therefore,a prediction based on such power functions can reach a satisfactory estimation with errors no larger than 3%for the commonly used cases with an equivalent radius of the FPB from 3 m to 6 m and friction coefficient from 0.03 to 0.06,a ratio of the yield strength to the weight of the girder from 0 to 0.2,yield displacement from 0.01 m to 0.03 m and a ratio of post-yield stiffness to elastic stiffness from 0.01 to 0.03 of the steel damper,respectively.Furthermore,a benchmark finite element model for a typical high-speed railway bridge was built and a comprehensive sampling for various isolation design projects was conducted and nonlinear time history analysis was carried out under 12 ground motions for each case.The results show that the seismic responses predicted with the equivalent linear analytical method are consistent with the average results from time history analyses.However,individual ground motion has a significant influence on the seismic response and the results from the twelve ground motions show significant dispersion even though they all well matched the target spectrum.It is suggested to take the prediction based on the analytical method preferentially for the seismic isolation design or to use a comprehensive result from the two types of methods.In addition,the equation for the calculation of the damping coefficient in the seismic design code of highway bridges led to better prediction and thus is proposed.关键词
铁路桥梁/减隔震设计/等效线性化原理/显式计算方法/阻尼调整系数Key words
railway bridges/isolation design/equivalent linear analysis/explicit analytical method/damping coefficient分类
天文与地球科学引用本文复制引用
苏伟,李晓波,王雨权,国巍,管仲国..铁路桥梁典型减隔震设计显式计算方法[J].铁道科学与工程学报,2025,22(2):712-722,11.基金项目
国家自然科学基金资助项目(52278527) （52278527）
中国国家铁路集团有限公司科技研究开发计划(K2022G009) （K2022G009）
