摘要
采用光滑函数技术,对拉压不同弹性模量问题的应力应变关系进行光滑处理,可避免迭代中应力状态的判断,方便计算。同时建立了相应的基于初应力技术的有限元计算模式,仅需对刚度阵三角化一次,避免了考虑剪切刚度带来的不便。文中通过不同算例,对所提算法进行了数值验证,与解析解相比有很好符合。此外,对不同拉压模量的热应力分析进行了初步探讨。
Constitutive non-linearity and discontinuity are dominant difficulties in solving elastic himodular problems either analytically or numerically. In this paper, maximum/mimimum functions are utilized to describe the non-linear relationship of stress and strain, and smoothly approximated by a set of entropy principle based smoothing functions. The smoothed constitutive equation is combined with an initial stress scheme to set up a FEM based numerical model that may lead to a higher computing efficiency since the stiffness matrix needs to be triangularized one time only in the whole computing process, and can avoid the inconvenience induced by choosing shear modulus. 8-node iso-parameteric finite element is adopted in the computing. A number of numerical examples are presented to verify the proposed algorithm, and compared satisfactorily with other solutions. Additionally, A bi-modular thermal stress analysis is given.
出处
《计算力学学报》
EI
CAS
CSCD
北大核心
2006年第1期19-23,共5页
Chinese Journal of Computational Mechanics
基金
国家自然科学基金(101720241042100210472019)
973项目(2005CB321704)
辽宁省中青年学术带头人基金资助项目
关键词
不同弹性模量
光滑函数
初应力法
有限元
热应力
dual extension-compression modulus
smooth function
initial stress
finite element
thermal stress
