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

作　　者：苏伟 李晓波 王雨权 国巍[3] 管仲国[4] SU Wei;LI Xiaobo;WANG Yuquan;GUO Wei;GUAN Zhongguo(School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China;China Railway Design Corporation,Tianjin 300308,China;School of Civil Engineering,Central South University,Changsha 410075,China;State key Laboratory of Disaster Reduction in Civil Engineering,Tongji University,Shanghai 200092,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]中国铁路设计集团有限公司,天津300308 [3]中南大学土木工程学院,湖南长沙410075 [4]同济大学土木工程防灾全国重点实验室,上海200092

出　　处：《铁道科学与工程学报》2025年第2期712-722,共11页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(52278527);中国国家铁路集团有限公司科技研究开发计划(K2022G009)。

摘　　要：高烈度区铁路桥梁减隔震设计广泛使用位移依赖型的摩擦摆支座与钢阻尼器组合减震体系,设计时采用非线性时域分析方法费时费力,而国内外减隔震设计规范中推荐的基于等效线性化原理的解析方法由于是隐式求解过程,需要迭代计算。结合铁路桥梁的结构受力特点,针对等效线性化解析方法,提出了高精度等代显式计算方法。通过减隔震系统设计参数全面系统的参数抽样分析,检验了该方法的计算误差。结果显示:组合减震体系的支座位移响应可以很好地表征为1 s周期的反应谱值的幂函数,由此建立的显式计算方法在常用的设计参数界限范围内,即摩擦摆支座等效回转半径3~6 m、摩擦因数0.03~0.06,钢阻尼器屈服力与梁恒载总重之比0~0.2、钢阻尼器屈服位移0.01~0.03 m、屈后与屈前刚度比0.01~0.03范围内,误差均少于3%。进一步基于典型高速铁路桥梁建立有限元基准分析模型,开展了大量的减隔震设计方案参数抽样,每个工况进行了12条地震波作用下的非线性时程分析,结果证实基于等效线性化原理的解析方法与非线性时域分析的平均结果之间具有较好的一致性,但非线性时程方法的分析结果受具体地震波的影响较大,即使对应同一目标谱,与之相协调的不同地震波仍会产生较大的离散性,建议在设计实践中优先选择等效线性化解析方法或者综合考虑2种算法的结果。此外,建议阻尼调整系数采用我国公路抗震设计规范的建议公式。The isolation system in combination with displacement-dependent friction pendulum bearings 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 sig

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 

分 类 号：P315.9[天文地球—地震学]