Lemaitre损伤模型的两种数值算法及其对比

基于Lemaitre损伤模型,采用2种简化的本构积分算法,对三维应力状态下各向同性塑性损伤问题进行计算。利用MATLAB语言编写相应的求解程序,分析不同应力状态下材料的损伤破坏过程,对比2种算法的计算精度与计算效率。结果表明:2种本构积分算法的计算结果均与理论解一致,能够适用于复杂应力状态下三维结构损伤与破坏分析;相比于应力与损伤耦合更新的算法,在增量步内将应力与损伤解耦更新的弱耦合算法可以更好地提高计算效率。

Two numerical algorithms of Lemaitre damage model and the comparison

In this paper, two kinds of simplified constitutive integral algorithm are adopted to solve the problem of isotropic plastic damage under three-dimensional stress state based on the Lemaitre damage model. The solving program compiled by the MATLAB was applied to analyze the failure process of materials under different stress states, and then, the accuracy and efficiency of two algorithms were compared. The numerical simulation shows that both the results of two integral algorithms agree well with theoretical solutions, and are capable to the analysis of damage and fracture of a three-dimensional structure under complex stress state. Compared to the updating algorithm that couples the stress and damage, the weak coupling algorithm that decoupling stress updating and damage in incremental step can better improve the computational efficiency.