弹性模量缩减法分析杆系和板壳结构的极限承载力  

THE ELASTIC MODULUS REDUCTION METHOD FOR LOAD CARRYING CAPACITY EVALUATION OF FRAME,PLATE AND SHELL STRUCTURES

作　　者：杨绿峰[1] 余波[1] 张伟[1] 

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

出　　处：《工程力学》2009年第12期64-70,共7页Engineering Mechanics

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基金项目(NCET-04-0834);广西自然科学基金重点项目(北部湾海洋环境下建筑结构失效机理及整体安全性研究)(桂科自0991020Z)

摘　　要：根据广义屈服准则定义了杆系和板壳结构的单元承载比,建立了承载比均匀度和基准承载比的计算表达式,然后通过弹性有限元迭代分析系统地缩减高承载比单元的弹性模量,使得结构中的单元承载比逐渐缩减,进而求得极限荷载下限,从而建立了以单元承载比为控制参数的弹性模量缩减法,并应用于构件截面几何尺寸或材料性能不同的复杂结构的极限承载力分析中,扩大了弹性模量调整法的应用范围。利用该方法计算了梁、刚架、桁架、板和壳等结构的极限承载力,并分析了结构的失效模式和影响因素。通过和弹塑性增量法的比较,证明了弹性模量缩减法具有较强的适应性、较高的计算精度和计算效率。The Elastic Modulus Reduction Method for elastic modulus adjustment is proposed for load carrying capacity evaluation of frame, plate and shell structures based on the element bearing ratio （EBR） in this paper. The EBR is defined based on the generalized yield criterion, then the reference EBR are determined by introducing the extremums and the degree of uniformity of EBR in structure. The elastic modulus in the element with an EBR greater than the reference one is reduced based on the equilibrium of strain energy. The lower-bound ultimate loads are analyzed for structures by the proposed method and the results yielded are compared with those by the Elasto-plastic incremental method, which demonstrates the flexibility, accuracy and efficiency of the proposed method.

关 键 词：极限承载力 弹性模量缩减法 单元承载比 有限元 迭代分析 

分 类 号：TU313.3[建筑科学—结构工程]