Abstract: The failure load, failure mode, and progressive damage processes of carbon-glass hybrid composite bolted connection structures were studied by using the method of experiments and numerical simulations. Based on the ABAQUS platform, the finite element models of 36 different types of connection structures with various width to diameter ratios(W/D) and end to diameter ratios(E/D) were established. According to the three-dimensional Hashin failure criterion and Chang-Chang failure criterion, the effects of structural dimensions E/D and W/D on the failure load and failure mode were analyzed, combined with the findings of the tensile tests. The impacts of E/D and W/D on the failure load and failure mode of the connection structures and the progressive damage processes of the connection structures under various failure modes were discussed. The results show that the failure modes of the carbon-glass hybrid composite bolted connection structures with a specific hybrid ratio include bearing failure, shear-bearing failure, and tensile failure. The structural dimensions E/D and W/D have a greater impact on the failure load and failure mode. The bearing failure mode of the connection structures is that the matrix of the laminated plates are damaged at the axis position on the extruding side of the bolt holes, and the failure extends outward in a sector shape along the axis to the structure failure. The shear-bearing failure mode is that a large number of fiber and matrix tensile damage occur from the bolt holes to the end face of the laminated plates, with the matrix bearing damage at the compression side of the bolt holes, generating a notch to the structural failure. The tensile failure mode is that the fiber and matrix tensile damage occurs at the upper and lower positions of the bolt holes of the laminates, and extends laterally to the upper and lower sides of the laminates, resulting in structural failure.

Key words:  , hybrid composite, mechanical connection, failure load, failure mode, progressive damage analysis

摘要： 采用试验和数值模拟相结合的方法，研究碳玻混杂复合材料螺栓连接结构的失效载荷、失效模式及其渐进损伤过程。基于ABAQUS平台建立了36种不同宽径比（W/D）、端径比（E/D）连接结构的有限元模型。根据三维Hashin失效准则和三维Chang-Chang失效准则，结合连接结构的拉伸试验，分析了结构尺寸E/D、W/D对失效载荷和失效模式的影响，探讨了不同失效模式下的渐进损伤过程。研究结果表明，一定混杂比的碳玻复合材料螺栓连接结构的失效主要有挤压失效、剪切挤压混合失效、拉伸失效三种模式;连接结构的结构尺寸E/D、W/D对结构的失效载荷和失效模式影响较大;连接结构的挤压失效模式是层合板在螺栓孔挤压边轴线位置发生基体挤压损伤，并沿轴线方向呈扇形向外扩展至结构失效；剪切挤压破坏模式是层合板在螺栓孔至端面处发生大量纤维和基体的拉伸损伤，伴随螺栓孔受压边基体挤压损伤，形成豁口至结构失效；拉伸失效模式是层合板在螺栓孔上下位置发生纤维和基体拉伸损伤，并沿横向扩展至层合板上下边缘至结构失效。 

关键词: 混杂复合材料, 机械连接, 失效载荷, 失效模式, 渐进损伤分析