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为了揭示轴向压缩载荷与径向冲击载荷共同作用下复合材料壳体开孔处裂纹的产生机理,开展了含圆孔复合材料圆柱壳冲击试验,并对冲击试验进行了有限元仿真分析。提出复杂冲击载荷作用下的动态响应分析方法,运用LS-DYNA对冲击载荷作用下含圆孔复合材料圆柱壳动态响应过程进行了模拟,采用含刚度退化的Chang-Chang失效准则预测复合材料圆柱壳破坏过程,得到的冲击加速度响应曲线及破坏区域与试验结果一致,验证了本文方法的正确性。对有限元模型进行动力学及静力学破坏分析,结果表明,径向冲击引起的环向拉应力是圆孔边缘破坏区域90°铺层纤维断裂与基体开裂的主要原因,而拉应力只引起0°铺层基体开裂。由破坏起始分析可知,将复合材料圆柱壳90°铺层含量由20%提高至50%,可使结构承载能力增加56%。
In order to reveal the mechanism of the cracking of composite shell under the action of axial compression load and radial impact load, the impact test of cylindrical shell with round hole composite was carried out, and the impact test was simulated by finite element method. The dynamic response analysis method under complex impact load is proposed. The dynamic response of circular cylindrical composite shell with impact load is simulated by using LS-DYNA. The Chang-Chang failure criterion with stiffness degradation is used to predict the dynamic response of composite cylindrical shell The damage process, the obtained impact acceleration response curve and the damage area are consistent with the experimental results, which verify the correctness of the proposed method. The results of dynamic and static failure analysis of the finite element model show that the circumferential tensile stress caused by radial impact is the main reason for the fiber breakage and matrix cracking in the 90 ° ductile region at the edge of the circular hole, ° Layered substrate cracked. From the initial analysis of failure, it can be seen that increasing the 90 ° ply content of the composite cylindrical shell from 20% to 50% can increase the structural carrying capacity by 56%.