A multi-scale rate dependent crack model for quasi-brittle heterogeneous materials
A multi-scale rate dependent crack model for quasi-brittle heterogeneous materials
复制标题
DOI：
10.1016/j.engfracmech.2013.03.009
复制
发表时间：
2013-05
影响因子：
5.4
通讯作者：
A. Karamnejad;Vinh Phu Nguyen;L. Sluys
中科院分区：
文献类型：
--
作者：
A. Karamnejad;Vinh Phu Nguyen;L. Sluys
提出了非均质准脆性材料在动载荷作用下开裂的多尺度数值模拟方法。该模型在宏观尺度上采用不连续裂纹模型模拟断裂，在细观尺度上采用梯度增强损伤模型模拟弥漫性损伤。通过不连续计算均质化方法，从中尺度得到了宏观黏结区模型的牵引-分离规律。采用隐式时间积分法在宏观尺度上求解动态问题，而将中尺度模型求解为准静态问题。通过将细观尺度模型的材料特性与宏观裂纹打开率联系起来，考虑裂纹打开率对宏观黏结规律的影响。对于波传播问题，模型响应相对于代表性体元尺寸的客观性得到了证明。通过与直接数值模拟的对比，验证了模型的正确性。
A multi-scale numerical approach for modeling cracking in heterogeneous quasi-brittle materials under dynamic loading is presented. In the model, a discontinuous crack model is used at macro-scale to simulate fracture and a gradient-enhanced damage model has been used at meso-scale to simulate diffuse damage. The traction-separation law for the cohesive zone model at macro-scale is obtained from the meso-scale through the discontinuous computational homogenization method. An implicit time integration is used to solve the dynamic problem at the macro-scale while the meso-scale model is solved as a quasi-static problem. The effect of crack opening rate on the macro cohesive law is taken into account by relating the material properties of the meso-scale model to the macro crack opening rate. The objectivity of the model response with respect to the representative volume element size is demonstrated for wave propagation problems. The model is verified by comparison with a direct numerical simulation.