多点激励下隔震桥梁非线性随机振动的时域显式迭代模拟法  

A SIMULATION METHOD BASED ON EXPLICIT TIME-DOMAIN ITERATION SCHEME FOR NONLINEAR RANDOM VIBRATION ANALYSIS OF ISOLATED BRIDGES UNDER MULTI-SUPPORT EXCITATION

作　　者：贾少敏[1] 王子琦 赵雷[1] 马海涛 JIA Shao-min;WANG Zi-qi;ZHAO Lei;MA Hai-tao(School of Civil Engineering,Southwest Jiaotong University,Chengdu,Sichuan 610031,China;Earthquake Engineering Research and Test Center,Guangzhou University,Guangzhou,Guangdong 510405,China)

机构地区：[1]西南交通大学土木工程学院,四川成都610031 [2]广州大学工程抗震研究中心,广东广州510405

出　　处：《工程力学》2018年第12期116-123,共8页Engineering Mechanics

基　　金：高性能计算重点专项项目(2016YFB0200605);国家自然科学基金青年科学基金项目(51808149);广东省自然科学基金项目(2018A030310067)

摘　　要：由于地震动的随机性与空间变异性、隔震支座的非线性特征及其安装数目少的特点,隔震桥梁地震响应分析是一典型的多输入局部非线性随机振动问题。采用Bouc-Wen模型描述隔震支座的非线性恢复力,建立多点地震激励下隔震桥梁结构的运动方程,并将得到的非线性运动方程改写为关于状态变量的拟线性方程,基于精细时程积分法和龙格-库塔法构造拟线性方程及隔震支座滞回位移方程的时域显式降维迭代求解格式。再以此高效算法为基础,应用随机模拟法计算多点激励下隔震桥梁随机地震响应的统计量。数值算例表明,所建立的方法计算速度快、精度高,可用于实际桥梁结构的抗震性能验算。Due to the randomness and the spatial variability of ground motion, the nonlinear behavior of isolation bearings and the limited number of isolation bearings installed in each bridge, the seismic response analysis of an isolated bridges is a typical multi-input locally nonlinear random vibration problem. The Bouc-Wen model is used to describe the nonlinear restoring force of isolation bearings, and then the nonlinear equation of motion of isolated bridges under multi-support seismic excitation is established. The nonlinear equation of motion is rewritten as a quasi-linear equation expressed in terms of state variables. Based on the precise time-integration method and the Range-Kutta method, an explicit time-domain dimension-reduced iteration scheme is established. Using this efficient scheme, the statistical characteristics of the random seismic responses of isolated bridges under multi-support seismic excitation are calculated by stochastic simulation. Numerical examples show the efficiency of the proposed approach and its application in the nonlinear random vibration analysis of isolated bridges under multi-support seismic excitation.

关 键 词：隔震桥梁 非线性随机振动 时域显式降维迭代 精细时程积分法 龙格-库塔法 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]