基于预插内聚力单元的混凝土模型生成方法与单轴拉伸细观模拟研究

Research on Concrete Model Generation Method and Uniaxial Tensile Meso Simulation Based on Pre-inserted Cohesive Element

基于MATLAB软件对已有的随机骨料投放算法进行优化,编写了一套更为简便高效的骨料生成与投放程序,建立了含随机凸多边形骨料的混凝土细观模型,利用C++自编代码,完成零厚度内聚力单元的批量插入,用于模拟混凝土内部单元的损伤与开裂。根据新建的基于预插内聚力单元的混凝土细观模型,选取合理的本构关系,以物理试验结果中抗拉强度和抗拉弹性模量为指标,开展混凝土单轴拉伸细观力学模拟研究,计算结果表明新建的预插内聚力模型生成算法具有可行性和有效性。

Based on MATLAB,the existing random aggregate placement algorithm is optimized,and a set of more simple and efficient aggregate generation and placement program is compiled.The meso model of concrete with random convex polygon aggregate is established and the batch insertion of zero thickness cohesive elements is completed by self-made C++code,which is used to simulate the damage and cracking of concrete internal elements.According to the proposed concrete meso model based on the pre-inserted cohesive element,the reasonable constitutive relationship is selected and the tensile strength and tensile elastic modulus obtained by physical experiments are taken as the index to carry out the meso mechanical simulation of concrete uniaxial tension.The calculation results show that the proposed generation algorithm of cohesive force model is feasible and effective.