A nonlocal treatment technique based on the background cell concept for micro-mechanical damage modeling
A nonlocal treatment technique based on the background cell concept for micro-mechanical damage modeling
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DOI：
10.1007/s00707-014-1268-0
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发表时间：
2014-12
期刊：
影响因子：
2.7
通讯作者：
Huan Li;Xiaofei Pan;Huang Yuan
中科院分区：
文献类型：
--
作者：
Huan Li;Xiaofei Pan;Huang Yuan
基于背景元的概念，提出了一种新的用于细观损伤建模的非局部处理方法。在修正的GTN损伤模型中，非局部损伤变量被定义为加权孔隙率，类似于无网格Galerkin方法。损伤变量的演化与积分点周围的支撑域有关。该算法是从规则的背景单元中提取的，并通过用户界面UMAT在商业有限元程序ABAQUS中实现，用于二维和三维问题。为了验证非局部损伤模型，对二维、三维裂纹试件和孔洞试件进行了大量的计算模拟，结果表明非局部损伤克服了网格敏感性，计算效率高于其他非局部处理方法。紧凑拉伸剪切试件的计算模拟表明，非局部损伤模型能够独立于单元取向来预测复合型裂纹的扩展。
In the present paper, a new nonlocal treatment for micro-mechanical damage modeling is introduced based on the background cell concept. The nonlocal damage variable in the modified GTN damage model is defined as the weighted porosity in analogy to the element-free Galerkin method. The evolution of the damage variable is related to the support domain surrounds the integration point. The efficient computational algorithm is taken from the regular background cell and implemented into the commercial finite element code ABAQUS via the user interface UMAT for both two-dimensional and three-dimensional problems. To verify the nonlocal damage model, extensive computational simulations of 2D and 3D cracked as well as holed specimens are presented and confirmed that the nonlocal damage overcomes mesh sensitivity and is computationally more efficient than other nonlocal treatment methods. The computational simulation of a compact-tension shear specimen reveals that the nonlocal damage model is able to predict mixed-mode crack growth independently of the element orientation.