集中塑性铰在网壳弹塑性地震响应中的应用  

Study on dynamic elastoplastic responses of single-layer reticulated shell structures under earthquake

作　　者：宋夏芸 李海旺[1] 张建媛[1] 

机构地区：[1]太原理工大学建筑与土木工程学院,山西太原030024

出　　处：《地震工程与工程振动》2015年第1期118-125,共8页Earthquake Engineering and Engineering Dynamics

基　　金：国家自然科学基金项目(50878137);山西省科技攻关项目(20080321086);山西省回国留学人员科研资助项目(2009-26)

摘　　要：运用SAP2000分析设计软件和集中塑性铰理论,对现有振动台试验模型进行弹塑性时程模拟分析,通过试验与模拟分析对比,验证集中塑性铰理论在空间网格结构弹塑性地震响应分析中的适用性。分析中考虑几何和材料双重非线性影响,获得了节点位移响应、杆件塑性铰的分布特征、结构的整体变形及失效形态。振动台试验与模拟分析均表明:单层网壳试验模型在地震作用下的破坏始于支座附近及靠近肋杆的斜杆杆件端部,最终破坏是由网壳模型底部第一圈、第二圈结构杆件动力失稳破坏引起的,模型底部第一圈、第二圈大部分杆件经历了失稳或较大塑性变形,部分杆件达到极限强度与节点拉脱,使结构整体向下凹陷;采用集中塑性铰方法模拟杆系结构的动力弹塑性性能与振动台试验结果基本吻合,较适用于空间杆系结构地震下的弹塑性性能评定,且易被工程师掌握。With SAP2000 software and concentrated plastic hinge theory, elastic-plastic time histoPy analysis is car- ried out for the existing test model on shaking table. By comparison with test and simulation analysis, the applica- bility of concentrated plastic hinge theory in the elastic-plastic seismic response analysis of spacial grid structure is verified. The node displacement responses, its plastic hinge distributions, the deformation mode and failure pat- terns and structural ductility coefficient are obtained. Shaking table test and simulation analysis have shown that, under the action of earthquake, the first damage occurs in the bearing and diagonal bars near the ribbed bar ends and the final damage caused by bar instability is at the bottom of the first lap and the second ring structure in net shell. Most of the bar at the bottom of the first lap and the second ring structure experience instability or larger plas- tic deformation. Part of the bars reachs ultimate strength and the node is pulled off, and the structure is overall col- lapsed down. With concentrated plastic hinge method to simulate dynamic elastic-plastic pertbrmance of the truss structure is basically consistent with the seismic test results and suitable for the elastic-plastic performance evalua- tion of the large-span spacial truss structure under earthquake and is easy to master by engineers.

关 键 词：单层网壳结构 弹塑性时程分析 集中塑性铰 动力失稳破坏 模拟试验分析 

分 类 号：TU393.3[建筑科学—结构工程] P315.92[天文地球—地震学]