基于CDM的开口复合材料层合板结构损伤问题研究

为研究含开口复合材料层合板结构在面内载荷作用下的损伤破坏问题，基于CDM基本原理，从平面应力状态下的Gibbs自由能出发，建立描述复合材料层合板结构层内断裂破坏的二维渐进损伤关系；基于ABAQUS材料用户子程序，将上述渐进损伤关系与二维Hashin失效准则相结合，开发复合材料损伤本构模型，并对含开口复合材料层合板结构在拉伸载荷作用下的破坏过程进行数值模拟；通过与文献试验数据的对比，证明该模型在平面拉伸载荷状态下可以有效预测含开口层合板结构的损伤起始与扩展过程，对层合板强度的预测误差较小。应用上述模型对三种不同开口类型层合板结构在剪切载荷作用的下损伤、破坏分析，结果表明：对于相同面积的开口，不同的开口类型会导致层合板抗剪强度产生较大的差异；而在铺层相同情况下，椭圆形开口层合板的剪切强度相对较高。

Damage and failure study of composite laminates with reinforced cutout based on CDM

Based on the continuum damage mechanics theory and Gibbs free energy principle, a two dimensional progressive damage model is built to describe the damage and failure process of composite laminates under the plane stress state. This damage mode is combined with the Hashin damage criterion and coded by the ABAQUS user subroutine as a new damage constitutive model for composite laminates. To verify its capacity, a FE model with above damage constitutive is applied to analyze the damage onset and propagation of the composite laminates with centric cutout and compared with the experimental, and the comparable results shows the above damage constitutive has relative high capability in describing the laminates structural damage propagation processes. This material model is further used to study damage evolution in different layers for laminates with three different cutout-shapes under the shear load, and the results shows the cutout-shape has very sensitive influence in damage and failure processes of composite laminates.