接头局部增强的复合材料层合板螺栓连接试验与数值模拟

采用真空辅助成型工艺（VARI）制备了四种局部增强的复合材料层合板螺栓连接试件，通过试验及数值模拟对其力学性能进行了研究。数值研究中将复合材料层合板连接件的拉伸作为一个准静态问题，运用ABAQUS的显示分析算法及所编写用户材料子程序VUMAT对连接件进行了三维渐进失效模拟，同时在有限元模型中采用内聚力单元模拟了层合板与所设增强层的界面分层失效。数值计算结果与试验结果取得了较好的一致，验证了本文中数值方法的有效性。研究结果表明，不同的局部增强方案对复合材料螺栓连接性能的影响较大，设置0/90/0/90]_S铺层的内置纤维增强层能显著提高层合板的螺栓连接性能。

Experimental and numerical simulation of composite laminates bolted joints with local reinforcement

Four different composite laminates specimens of bolted joints with local reinforcement were prepared by vacuum assisted resin injection molding (VARI). The mechanical behavior of the composite bolted joints specimens was experimental and numerical investigated. In the numerical study, the bolted of static tensile was deemed to a quasi static problem. An explicit dynamic solver and ABAQUS user subroutine VUMAT were implemented to simulate the 3D progressive failure process of composite bolted joints. Interface delamination was simulationed using a cohesive element layer between laminates and reinforcement layer. The numerical results are in good correlation with the experimental results, which demonstrate that the simulation is feasible. The research results show that bolted joints with different local reinforcement methods affect connection properties of laminates obviously, and the connection properties of laminates are significantly improved by 0/90/0/90]_S internal fiber layer reinforcement.