地震下某三心圆双向钢桁架结构体系动力弹塑性失效分析  

Study on Dynamic Elastic-plastic Failure Analysis of Bi-directional Three Centered Steel Pipe Arch Truss Structure System under Seismic Action

作　　者：宋夏芸 李海旺[1] 吴鹏程[1] 

机构地区：[1]太原理工大学建筑与土木工程学院,太原030024

出　　处：《防灾减灾工程学报》2015年第3期398-403,共6页Journal of Disaster Prevention and Mitigation Engineering

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项目(2009-26)资助

摘　　要：运用SAP2000结构分析软件与塑性铰理论,对某兼具地震避难所功能的三心圆双向钢管拱桁架结构的大跨公共建筑进行了地震波作用下的动力弹塑性性能分析,考虑了几何和材料双重非线性影响,获得了结构的变形形态、失效类型、塑性发展程度和延性性能,并基于其失效形态对强震下的抗震性能进行了评定。结果表明:该结构在强震作用下的失效模式是,三心圆拱桁架在变曲率处和支座处的关键弦杆、腹杆陆续进入不同阶段的塑性铰并形成局部塑性铰集中区域,导致结构沦为机构而失效;该结构在地震波下的失效界限地震加速度峰值为595gal,最大竖向变形为跨度的1/207,结构各方向延性系数均大于4,具有较好的塑性变形能力,可满足8度抗震设防区在罕遇地震作用下的安全性能要求。Using SAP2000 software and plastic hinge theory,the dynamic elastic-plastic performance analysis of a long-span public structure is carried out under different earthquake ground motions.In the analysis both geometric and material nonlinear effects are taken into consideration.The plastic hinge distributions,and the deformation mode and failure patterns,and the ductility performance are obtained.Based on the failure forms the seismic performance under strong seismic action is evaluated.The results show that：the structure failure type is that the key chords and webs in the curvature change position and near the bearings gradually enter different stages of the plastic hinge and form a local plastic hinge concentrated area,and finally lead to the structure failure;Under seismic ground motion,the assessed failure peak value of the earthquake acceleration is 595 gal and its corresponding maximum vertical displacement is 1/207 of the span,the structural ductility coefficients in each direction is greater than 4,the plastic deformation ability is great,which could meet the requirements of the safe work performance of earthquake refuge in the area with seismic intensity Ⅷ.

关 键 词：双向钢管拱桁架 动力弹塑性分析 塑性铰 失效分析 地震避难所 

分 类 号：TU998.1[建筑科学—市政工程]