反力墙实验系统的静力有限元分析

Static Finite Element Method(FEM) Analysis of Reacting-Force Wall System

对某校土木工程实验中心的反力墙实验系统进行了静力有限元分析。讨论了有限元单元类型,材料参数的计算和混凝土破坏准则的参数选择。通过计算机仿真加载试验,得到考虑加载孔削弱后等效的混凝土单轴抗拉强度,从而对有加载孔的反力墙和台座模型进行了简化。因主要关注的是预应力反力墙结构的整体性能,故选择了分离式等效载荷法作为预应力施加方法,以分析预应力对结构的整体效应。对荷载步进行了设计,以清楚显现预应力大小对结构变形和应力的影响。计算结果表明,预应力的施加能减少位移,减小拉应力;反力墙系统能满足变形、强度和抗裂度要求。

The experimental system of reacting-force wall and test-bed was analyzed by static finite element method.Selection of element types, calculation of material parameters and selection of parameters of yield criteria were discussed.Equivalent tensile strength of concrete allowing for loading holes was obtained by computer loading experiment.So the model of the reacting-force wall and test-bed with loading holes was simplified.For the whole performance of the prestress system was prinicipally concerned, an equivalent loading method was adopted as prestressing method, which was used to analyze the whole effect of prestress on the structure.Load steps are designed to clearly show the influence of prestress on deform and stress of the system.The result shows that prestress can reduce the deform and tensile stress.The reacting-force wall system can meet the demands of deform, strength and anti-crack.