两种改进虚拟激励法比较及大跨结构的行波效应分析  

Comparison Between Two Improved Pseudo-Excitation Methods and Analysis of Long-Span Structural Travelling Wave Effects

作　　者：张婷[1] 陈清军[1] 杨永胜[1] 

机构地区：[1]同济大学土木工程防灾国家重点实验室,上海200092

出　　处：《力学季刊》2012年第4期612-619,共8页Chinese Quarterly of Mechanics

基　　金：国家自然科学基金资助(90915011);科技部国家重点实验室基础研究资助项目(SLDRCE08-B-03)

摘　　要：选择高效且易实现的分析方法是实现大跨度结构多点随机地震反应分析的关键步骤之一。首先,对两种改进的虚拟激励法(即直接位移求解法和大质量法)做了简要比较;然后,通过对ANSYS程序的二次开发,实现了直接位移求解法和大质量法的通用有限元计算,进行了这两种改进虚拟激励法的数值精度比较。在此基础上,选择高精度的直接位移求解的虚拟激励法,以能较好模拟长周期地震动特性的杜修力陈厚群功率谱模型作为输入,对某悬索桥结构进行了多点随机地震反应分析,探讨了大跨度结构的响应峰值随地面视波速变化、以及行波效应对结构不同部位反应的影响。Selection of analysis methods with high efficiency and easy operation is a key step to carry out the analysis of multi-support random seismic response of long-span structures. Firstly, the paper makes a brief comparison was presented between two improved pseudo-excitation methods（e, g. direct displace- ment method and large mass method） ; secondly,through the secondary development of ANSYS program, the finite element calculation of direct displacement method and large mass method are both achieved, and the comparison between the numerical accuracy of such two improved pseudo-excitation methods is carried out. Furthermore,direct displacement pseudo-excitation method with high-precision was chosen in order to better simulate the long-period ground motion characteristics of the Du Xiuli-Chen Houqun power spec-trum model as the input,and the multi-point random earthquake response analysis on a suspension bridge structure was made. Then the peak response of long-span structure with the varying wave velocity and the traveling wave effects on different parts of the structure were discussed.

关 键 词：改进虚拟激励法 大跨度结构 多点随机地震反应 通用程序二次开发 数值对比分析 

分 类 号：TU311.3[建筑科学—结构工程]