用弹性模量缩减法分析刚架结构的极限承载力  

Ultimate Load Bearing Capacity Evaluation of Frame Structures by an Elastic Modulus Reduction Method

作　　者：杨绿峰[1] 余波[1] 乔永平[1] 

机构地区：[1]广西大学土木建筑工程学院广西大学工程防灾与结构安全教育部及广西重点实验室,南宁530004

出　　处：《防灾减灾工程学报》2009年第3期306-312,共7页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(50768001);教育部新世纪优秀人才支持计划专项(NCET-04-0834);广西自然科学基金项目(桂科自0728026)资助

摘　　要：首先,综合考虑单元的内力和屈服强度,定义了单元承载比、承载比均匀度以及基准承载比等参数的概念和计算表达式;在此基础上,根据相邻迭代步变形能守恒关系,研究建立弹性模量的调整计算公式,建立了一种新型的弹性模量调整策略;进而提出了刚架结构极限承载力分析的弹性模量缩减法,即通过系统地调整高承载比单元的弹性模量来确定结构的极限荷载下限值。该方法对于结构的局部破坏模式及整体破坏模式分析均具有较好的适用性。算例分析表明,本文方法具有较高的计算精度和计算效率。An elastic modulus reduction method is proposed for the ultimate load bearing capacity evaluation of frame structures, based on the element bearing ratio （EBR） and the conservation of strain energy. The EBR is defined for discrete elements by either employing the generalized yield criteria or a dominant inner force. Then the reference EBR is selected according to the degree of uniformity as well as the extremum of EBRs in the structure. The elastic modulus in the element with a higher EBR, compared to the reference one, is reduced according to the linear elastic finite element analysis and the conservation of strain energy. A lower-hound of the ultimate load bearing capacity of the frame structure is determined finally. The numerical examples in this paper have demonstrated the flexibility, accuracy and efficiency of the proposed method.

关 键 词：刚架结构 极限承载力 弹性模量缩减法 单元承载比 动态模量调整因子 

分 类 号：TU313.3[建筑科学—结构工程]