铁路桥梁摩擦摆减隔震体系简化分析方法  

Simplified analysis method for friction pendulum seismic reduction and isolation system of railway bridge

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 Co,Ltd,Tianjin 300308,China;School of Civil Engineering,Central South University,Changsha 410075,China;State Key Lab of Disaster Prevention 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,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,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：《振动与冲击》2025年第7期124-131,共8页Journal of Vibration and Shock

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

摘　　要：高烈度铁路桥梁减隔震设计广泛使用摩擦摆支座,采用非线性时域分析方法费时费力,等效线性化分析方法是个隐式求解过程,不仅需要迭代计算,而且由于铁路桥墩下部结构体量很大,仅基于首阶振型可能显著低估桥墩的地震响应。结合铁路桥梁的结构受力特点,基于等效线性化原理,提出高精度等代显式计算方法,用于求解摩擦摆减隔震支座的地震响应,提出考虑首阶振型与墩身自振振型组合的简化求解方法,用于求解桥墩地震响应。参数分析结果显示,减隔震支座的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,由此建立的简化显式计算方法在常用的设计参数范围内,即摩擦摆支座等效回转半径3~6 m、摩擦因数0.03~0.06,误差小于3%。进一步基于典型高速铁路桥梁,建立结构分析基准模型,通过变化墩高和基础刚度、摩擦摆支座回转半径和摩擦因数、地震作用强度,开展了200个参数抽样,对每个抽样又进行了12条地震波作用的非线性时程分析。结果显示:简化显式计算方法与非线性时域分析的平均结果之间具有很好的一致性,考虑首阶振型与墩身自振振型组合的简化求解方法也能很好地估计各样本的墩底剪力和弯矩响应,而仅考虑首阶振型平均偏低估计墩底剪力和弯矩分别约为40%和30%。Friction pendulum pedestals are widely used in seismic reduction and isolation design of railway bridges in high-intensity earthquake zones.Nonlinear time-domain analysis methods are time-consuming and laborious,while equivalent linearization analysis method is an implicit solving process requiring iterative calculations,due to large volume of lower structure of railway bridge piers,only using the first-order vibration mode may significantly underestimate seismic responses of piers.Here,based on structural stress characteristics of railway bridges and the principle of equivalent linearization,a high-precision equivalent explicit calculation method was proposed to solve seismic responses of friction pendulum seismic reduction and isolation pedestals.A simplified solving method considering combination of first-order vibration mode and pier body natural vibration modes was proposed to solve seismic responses of bridge piers.The parametric analysis results showed that displacement responses of seismic reduction and isolation pedestal can be well characterized as a power function of response spectrum value with a 1-second period,the simplified explicit calculation method established from this can be used within the commonly used design parameter ranges,i.e.,equivalent rotary radius of friction pendulum pedestal is 3-6 m and friction coefficient is 0.03-0.06,error is less than 3%.Further based on typical high-speed railway bridges,a structural analysis benchmark model was established.By changing pier height and foundation stiffness,friction pendulum pedestal rotary radius and friction coefficient as well as seismic intensity,200 parametric samples were made,for each sample,nonlinear time history analyses were performed under 12 seismic wave actions.The results showed that there is good consistency between the results of the simplified explicit calculation method and the average results of nonlinear time-domain analyses;the simplified solving method considering combination of the first-order mode and natural vibration m

关 键 词：铁路桥梁 摩擦摆减隔震支座 桥墩 等效线性化原理 简化分析方法 

分 类 号：U24[交通运输工程—道路与铁道工程]