复合材料T型接头疲劳分层损伤数值仿真研究

Numerical simulation study on delamination damage of composite T-joint under fatigue load

基于内聚力单元方法,开发自定义材料子程序,结合损伤判据和疲劳损伤演化准则,建立复合材料层间疲劳损伤计算模型,并通过有限元对复合材料T型接头层合结构在疲劳载荷下的分层扩展行为进行数值仿真研究,结果表明位移控制下裂纹初期扩展较快,之后裂纹长度增长载荷降低,扩展速率逐渐缓慢,载荷控制相反,裂纹因长度增长而加速扩展。

Based on the cohesive element method, a user-defined material subroutine is developed. Combined with the damage criterion and fatigue damage evolution criterion, the calculation model of interlaminar fatigue damage of composite materials is established. The delamination propagation behavior of T-joint laminated structure under fatigue load is numerically simulated by finite element method. The results show that under the control of displacement, the crack propagates rapidly at the initial stage. When the crack length increases and the load decreases, the propagation rate gradually slows down.On the contrary, the crack accelerates under the control of load due to the growth of length.