大坝有限元分析应力取值的研究  

STRESS EVALUATION IN FINITE ELEMENT ANALYSIS OF DAMS

作　　者：杨强[1] 吴浩[1] 周维垣[1] 

机构地区：[1]清华大学水利系,北京100084

出　　处：《工程力学》2006年第1期69-73,共5页Engineering Mechanics

基　　金：国家自然科学基金(50279016);973课题(2002cb412708)资助项目

摘　　要：提出了基于误差控制下的自适应网格的有限元应力取值标准:即给定一全局误差限作为自适应有限元网格剖分的准则,以此网格计算所得应力即为有限元应力取值。应用适用于工程计算的Z2后验误差估计方法以及h-型自适应策略,对一个典型的重力坝剖面进行了线弹性自适应有限元计算。计算结果表明:给定一个全局误差限,网格剖分调整若干次后即可满足误差要求,不会出现因角缘应力集中出现剖分不收敛的情况;存在一个全局误差限,使得当继续降低误差限时,坝踵和坝趾的角缘应力趋于稳定值。The stress evaluation based on adaptive finite element method is discussed. An optimized mesh, which is generated under control of a given global error limit, is used to evaluate stresses. The Zienkiewicz-Zhu a posteriori error estimator and corresponding h-version adaptive strategy are employed. The linear elastic adaptive finite element analysis is applied to a typical gravity dam. Results indicate that error limit is satisfied after several mesh adaptation. There exists a global error limit, which make the stresses at dam heel and toe asymptotically keep stabilization rather than increase without limit. As a global error limit 3% is suggested.

关 键 词：水工结构 大坝应力取值 自适应有限元 后验误差估计 容许误差限 

分 类 号：TV31[水利工程—水工结构工程]