中文摘要：

采用细观力学方法以及虚拟裂纹闭合法（VCCT）对含有Z-pin增强复合材料双悬臂梁（DCB）结构Ⅰ型断裂韧性进行了研究。利用有限元法建立了结构模型,采用实体单元模拟复合材料层压板结构和非线性弹簧元模拟Z-pin。通过计算应变能释放率对含有不同体积分数Z-pin的复合材料层压板Ⅰ型断裂韧性与不含Z-pin的复合材料层压板Ⅰ型断裂韧性进行了对比分析。研究表明,含有Z-pin增强复合材料双悬臂梁（DCB）结构Ⅰ型断裂韧性在裂纹扩展过程中受到Z-pin桥联作用的影响而显著增强,且其增强效果与Z-pin的体积分数、处在桥联区的Z-pin数目均相关,这表明Z-pin增强方法能够有效提高复合材料层压板的分层扩展阻力。

英文摘要：

The mode Ⅰ fracture toughness of Z-pin reinforced double cantilever beam configuration laminates was studied based on mesomechanics and virtual crack closure technique（VCCT）. A finite element model was built using solid elements to model the composite laminates and non- linear combined elements to simulate the Z- pin reinforcement. The numerical results of the strain energy release rate were compared between the fracture toughness of the mode Ⅰ composite laminate reinforced with the Z-pin and that of the mode Ⅰ composit＇e laminate without the Z-pin. The study demonstrates that Z-pin reinforcement can increase the composite delaminated resistance and reinforce the fracture toughness of the mode Ⅰ composite laminate aggressively. The influence of design parameters such as the number of Z-pin in the bridging area, the Z-pin density and some other parameters on the toughness enhancement of Z-pinned laminates was investigated.