基于改进点估计法的结构整体概率抗震能力分析

确定能力中位值和能力离差值是结构整体概率抗震能力分析的两个关键问题,文中分析了现有方法存在的缺点。在Zhao-Ono点估计法的基础上,引入基于随机向量边缘概率分布信息的Nataf变换,提出了改进的点估计法。将改进点估计法与Pushover分析相结合,提出了评估结构整体概率抗震能力统计矩的随机Pushover分析方法。以某五层三跨钢筋混凝土框架结构为例,应用本方法,进行结构整体概率抗震能力分析,得到了结构整体抗震能力的易损性曲线。分析表明,所提方法是一种具有较高效率和较好精度的结构整体概率抗震能力的分析方法。

Global probabilistic seismic capacity analysis based on an improved point estimation method

Determining the capacity median and evaluating the capacity dispersion are two key problems in global probabilistic seismic capacity analysis of structures,so the existing methods for the two problems are reviewed and analyzed.Based on Zhao-Ono point estimation method,an improved point estimation method is proposed by introducing Nataf transformation which can consider the marginal distribution information of the basic random variables.Combining the improved point estimation method with pushover analysis,a random pushover analysis method is put forward for assessing the statistical moments of global seismic capacities of structures.A five-storey RC frame structure with three-bay is taken as an example to run the probabilistic analysis of the global seismic capacities of the structures,so that the vulnerability curves of the global seismic capacities of the structures are derived.The results show that the method of this paper is a relatively highly efficient and exact method to analyze the global probabilistic seismic capacities of the structures.