平面框架结构的随机地震反应和抗震可靠度分析

地震地面加速度被模拟为均值为零的两次过滤高斯白噪声平稳过程，利用静力凝聚技术把结构简化为一维链状模型，在时域内推导出凝聚后的结构的协方差反应矩阵方程，采用一种简化的极限分析方法，通过纽马克能量等效准则把结构的非线性抗力值等效为线性抗力，给出结构极限状态概率的计算公式。

Stochastic earthquake responses and seismic reliability analysis of plane frame structures

A practical and simplified analysis method of random response and seismic reliability is de- veloped for earthquake-resistant structures in this paper. A static condensation technique is used to transform the frame structure into a stick model with lumped mass at each floor level. The earthquake ground acceleration is represented by a segment of stationary process of a twice filetered Gaussian white noise with mean zero, and a matrix equation of the covariance response of the condensed struc- ture is deduced by correlation method in time domain. The mean square displacement and velocity responses may be obtained directly by solving the matrix equation. A simplified limit analysis proce- dure is utilized to determine the failure mechanism, and the ultimate structural capacity is modified to the equivalent linear capacity by using Newmark's equal energy criterion. This procedure makes the structural random response evaluation linear so that difficulties of nonlinear random seismic response analysis will be eliminated. The limit state probability of the structure is measured in terms of every story limit state probabolity, and the frgility curve for the frame structure is generated by evaluating the limit state probabilities at different levels of peak ground acceleration. The annual limit state prob- ability of the frame structure can be also evaluated from the hazard curve for a site and the fragility curve for a structure.