复杂应力状态下砌体匀质化RVE数值模拟分析

Numerical simulation of homogenized masonry RVE under complex stress states

针对无筋砌体力学性能研究,基于匀质化理论,利用二次开发的有限元分析软件,考虑砌体RVE各边的应变状态,建立周期性边界条件,对砌体RVE匀质化过程中RVE单轴、双轴、三轴以及剪压复杂应力条件下的力学响应进行了数值模拟分析,得到了各状态下的应力应变曲线.分析结果表明,在受压状态下,砌体RVE受压应力应变曲线表现出一定塑性,并且双轴、三轴受压状态下RVE强度高于单轴受压;拉-压状态下,砌体RVE受拉应力应变曲线表现出材料脆性特性;拉-压-剪状态下,砌体RVE强度受剪压比、拉剪比影响,这些都很好地反映了无筋砌体的细观力学特性.

According to homogenization theory, this article focuses a study on mechanical properties of brick masonry. Considering strain state on each side of the RVE, periodic boundary conditions are established, in which constraint equation in finite element analysis is discussed and set up. Element analysis software of redevelopment is applied and with which stress-strain curve of RVE under equivalent stress states of homotaxial, uniaxial, blaxial, shear-compression. The analysis result shows that stress-strain curve of RVE pres- ents plastic characteristic and compressive strength of RVE is higher under uniaxial or blaxi- al state than that of homotaxial state. It can refer from tension stress strain curve that RVE presents fragile characteristic under state of tension-compression. Strength of RVE is influ- enced by different shear-compression ratio and shear-tension ratio under tension-shear-com- pression condition. All the results reflect the mechanical properties of brick masonry accu- rately on meso-level.