A multidirectional damage model based on continuum damage mechanics for fiber-reinforced composite laminates is proposed in this paper. The influence of three main damage mechanisms, including transverse matrix cracking, local delamination, and fiber breakage, on the multidirectional stiffness properties of composite laminates is analyzed by introducing macro phenomenological damage variables. Then the mechanical behavior of elementary ply in laminates is modeled based on these damage variables. Besides, relations between micro-level damage variables and macro-level damage variables are established. Damage evolution laws of the three damage mechanisms are proposed to predict the degradation of multidirectional stiffness and failure strength of composite laminates under quasi-static loading. The experiment of cross-ply glass fiber-reinforced plastic laminates is carried out, and the prediction results show good agreement with the experimental results.

中文翻译：

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纤维增强塑料层压板在静载荷下的多向损伤模型

提出了一种基于连续损伤力学的纤维增强复合材料层合板多向损伤模型。通过引入宏观现象学损伤变量，分析了横向基体开裂、局部分层和纤维断裂三种主要损伤机制对复合材料层合板多向刚度特性的影响。然后基于这些损伤变量对层压板中基本层的机械行为进行建模。此外，建立了微观损伤变量与宏观损伤变量之间的关系。提出了三种损伤机制的损伤演化规律，以预测准静态载荷下复合材料层合板多向刚度和破坏强度的退化。