三维杂交应力元性能分析的基本变形模式方法  

PERFORMANCE ANALYSIS OF 3D HYBRID STRESS ELEMENTS WITH A BASIC DEFORMATION-BASED APPROACH

作　　者：张灿辉[1] 王东东[1] 张建霖[1] 

机构地区：[1]厦门大学土木工程系,福建厦门361005

出　　处：《工程力学》2009年第8期44-49,共6页Engineering Mechanics

基　　金：福建省科技项目(2007F3096);厦门市科技项目(3502Z20073012);国家自然科学基金项目(10602049)

摘　　要：通过分离杂交元各阶模态所对应应力场求得单元基本变形模式,从而提出一种直接分析杂交元任意变形性能的基本变形模式方法。单元模态不仅和假设应力场有关而且是多种简单变形耦合而成的复杂变形,该文采用应力参数直接考察杂交元振型所对应的应力场,有效地把复杂的耦合应力场分离成一系列简单应力场的组合,进而在此基础上求得杂交元基本变形模式,克服了直接分离复杂振型的困难,可以对杂交元对于基本变形模式的变形刚度即单元性能进行简便有效的分析。通过对多种杂交元进行分析研究和数值计算,综合评价和对比了它们对于各种变形的性能,指出某些假设应力场只适用于特定问题的求解但不能用以形成通用的杂交元。The basic deformation modes of a hybrid stress element are obtained by separating the stress modes corresponding to the different deformation modes of a hybrid stress element. Consequently a basic deformation-based approach is presented to investigate the performance for a given hybrid stress element. It is shown that the element deformation modes generally depend upon the assumed stress fields and thus are complex and coupled. In the proposed approach, the coupled stress fields are expressed with the stress parameters such that they can be easily decoupled into the linear combination of a series of basic stress fields. The relevant basic deformation modes are derived and the rigidity of hybrid element for arbitrary deformation modes, namely the element performance can be directly studied. The difficulty associated with the decoupling of various deformation modes is completely avoided. Investigations show that some of these assumed stress fields can not be used to the general hybrid elements.

关 键 词：杂交应力元 基本变形模式 变形刚度 假设应力场 应力参数 

分 类 号：O242.21[理学—计算数学]