剪弯梁宏细观多尺度非线性有限元分析

为深入研究细观粗骨料粒径对混凝土宏观构件非线性力学性能的影响,通过生成满足Fuller级配的骨料粒径,以放置区域像素的RGB(红绿蓝)值判断骨料重叠情况,实现骨料在混凝土内部的随机分布.在此基础上,运用均匀化方法求解二维细观随机多边形骨料模型的等效弹性模量及刚度矩阵,并引入混凝土材料损伤因子模拟剪弯梁裂缝展开,由此构建...

Macro and Meso Multi-Scale Nonlinear Finite Element Analysis of Shear-Flexural Beam

In order to further study the influence of the mesoscopic coarse aggregate gradation on the nonlinear mechanical properties of concrete macroscopic components, the aggregate size satisfying Fuller grading was generated, and the aggregate overlap was judged by the RGB (red, green, bule) value of the placement area pixels, so as to realize the random distribution of aggregate in concrete. On this basis, the equivalent elastic modulus and stiffness matrix of two-dimensional mesoscopic random polygonal aggregate model were solved by homogenization method, and the damage factor of concrete material was introduced to simulate the crack expansion of shear-flexural beam, so a multi-scale nonlinear mechanical model of concrete was established. The results show that when the concrete enters the plastic stage, the correlation between the maximum aggregate size and the damage factor under tension and compression can not be ignored, which directly affects the crack development and the maximum plastic strain of the macroscopic shear-flexural beam. It may also change the failure mode of shear-flexural beam.