非协调元在温度应力场数值计算中的尝试  

Test of incompatible element in numerical calculation for thermal stress field

作　　者：何勇[1] 张南南 杨锐[3] 郭晓娜[4] 强晟[3] 

机构地区：[1]杭州市南排工程建设管理处,杭州310000 [2]浙江省水利水电勘测设计院,杭州310002 [3]河海大学水利水电学院,南京210098 [4]南水北调中线干线工程建设管理局,北京100038

出　　处：《南水北调与水利科技》2015年第B02期12-14,25,共4页South-to-North Water Transfers and Water Science & Technology

基　　金：国家自然科学基金“快速浇筑条件下混凝土坝施工期应力特性和防裂方法研究”（51109071）;浙江省水利厅科技重点项目“大型斜轴泵流道结构商品混凝土施工防裂方法研究”（2010105）

摘　　要：在计算结构的温度应力时，采用普通的8节点协调元会产生较大的误差，其中一个重要原因是应变的精度与温度的精度不匹配。为此，引入非协调元理论，在位移插值函数中补充了不协调位移项，虽然在相邻单元边界上位移函数出现了不连续，但是可以使得单元位移函数中的2次项或3次项趋于完全，从而提高其精度。针对温度应力场计算的特点，采用8节点非协调单元的位移插值函数，并用Fortran语言编成程序。算例验证结果表明：仿真计算中采用协调元计算温度场，采用非协调元计算应力场，其计算结果更接近理论值，是一种较好的匹配方案。When calculating the structure temperature stresses, the application of ordinary 8-node compatible element sometimes produces large error. One of the important reasons is that the accuracy of strain and temperature accuracy does not match. Therefore, the paper introduced the incompatible element theory, and incompatible displacement is added in the displacement interpolation function. Although discontinuous displace- ment function appears on the adjacent element boundaries, it can make the quadratic term and the cubic term become unbroken in the element displacement interpolation function,which can improve the accuracy. According to the characteristics of temperature stresses field calculation, the 8-node displacement interpolation function of incompatible element is employed and a Fortran language code is compiled. The example verifi- cation results show that it＇s a better matching scheme to obtain the temperature field by compatible element and to calculate the stress field by incompatible element in the simulation calculation, the result of which is closer to the theoretical value.

关 键 词：温度应力 协调元 非协调元 内部自由度 

分 类 号：TV3[水利工程—水工结构工程]