复合材料加筋板多失效模式可靠性分析

Reliability Analysis of stiffened composite plates with multiple failure modes

复合材料加筋板在轴向压缩的曲屈过程中,存在多种失效模式,对整体的可靠度有不同影响.本研究利用ABAQUS软件,建立由shell-solid单元组合的复合材料加筋板渐进失效模型,并基于Quads和Hanish失效判据,用Cohesive单元来模拟胶层,通过对模型轴向加位移的弯曲情况,确定刚心位置后,进行轴向加载仿真实验.通过有限元模拟方法,用均次一值二矩法计算可靠度,分析曲屈失效过程,影响可靠度的主要因素为静力.通过灵敏度分析,归一化计算,得到材料不同弹性模量对复合材料加筋板模型的基体失效、纤维失效、界面层失效和静力失效的贡献率.由失效判断指标可知,纤维失效是造成复合材料加筋板结构整体失效的主要因素,由灵敏度分析结果可知是影响基体失效、纤维失效、界面层失效的主要因素.

Composite stiffened plates under axial compression of a tortuous process, have many failure modes, and there are different impact on its entire reliability. By using Abaqus software to establish stiffened composite plates progressive failure model, the shell-solid elements to simulate the stiffened plates and beams, solid elements to simulate the layer , and cohesive unit to simulate the situation debonding layer.Through finite element simulation method using application of MFOSM to calculate reliability analysis under tortuous process, main factors influencing the reliability is static force. Through the sensitivity analysis, the normalized calculation, the rate of contribution was gotlen, with different elastic moduli of composite material model, that of substrate failure, fiber failure, interface layer failure and static of failure rate of contribution. The failure judgment index showed that fiber failure are the main factors causing failure of stiffened composite plates structure. The sensitivity analysis results show that the substrate failure, fibers failure, interface Layer failure, are the main factors.