LRB基础隔震结构非线性动力响应的非迭代时程计算方法  

NON-ITERATIVE COMPUTATIONAL METHOD FOR NONLINEAR TIME-HISTORY RESPONSE OF LBR BASE-ISOLATED STRUCTURES

作　　者：叶昆[1,2] 李黎[1,2] 龙晓鸿[1,2] 

机构地区：[1]华中科技大学土木工程与力学学院,武汉430074 [2]华中科技大学控制结构湖北省重点实验室,武汉430074

出　　处：《振动与冲击》2008年第11期46-50,共5页Journal of Vibration and Shock

基　　金：湖北省建设厅科技项目(K200553)

摘　　要：提出了一种求解使用铅芯橡胶支座(LRB)的基础隔震结构非线性动力响应的非迭代时程计算方法。该方法首先将层间剪力向量作为非线性二阶运动微分方程的参量,引入状态变量将非线性二阶运动微分方程降阶为一阶状态空间方程,通过使用描述非线性滞回模型的Masing准则确定隔震层剪力并给出了计算隔震层剪力的流程图,利用经典的Runge-Kutta方法进行求解。这样本文所提出的非迭代算法可以避免繁琐的迭代运算,方便编制程序。在数值试验中,利用本文提出的非迭代算法与传统的Newton-Raphson迭代算法进行了比较,结果表明:利用本文提出的非迭代算法得到的时程结果与使用Newton-Raphson迭代算法得到的时程结果十分接近并且峰值的相对误差比较小,能够满足工程计算的精度要求。Non-iterative computational method for the nonlinear time-history response of base-isolated structures e- quipped with lead-rubber hearings (LRB) was presented.In the method proposed,the base-isolated structure was mod- eled as inter-story shear model with bilinear hysteresis at the isolation level,and the inter-story shear force vector was used as variable in the nonlinear second-order differential equation of motion.By introducing state variables,the equation was reduced to first-order state-space differential equation.The shear force at the isolation level was determined by use of Mas- ing criteria,which is suitable for the nonlinear hysteretic model.The flow chart to calculate the shear force at the isolation level was provided.Classical Runge-Kutta method was used to solve the first-order state-space differential equation.The non-iterative computational method proposed can avoid the iterative operation and make programming easier.In the nu- merical experiment,comparison between the method proposed and the conventional Newton-Raphson iterative method was carried out,which shows that time-history results obtained by both methods are very close to each other.The relative er- rors are small and accuracy demand of engineering computation can be satisfied.

关 键 词：基础隔震结构 Masing规则 层间剪切模型 非线性地震反应 非迭代算法 

分 类 号：TU352.1[建筑科学—结构工程]