双面贴补层合板压缩屈曲渐进损伤分析

Progressive damage analysis of double-strap bonding repaired laminates under buckling compression

贴补复合材料层合板在压缩载荷作用下的屈曲破坏强度及其损伤演化过程对于复合材料结构修理具有重要意义。本文基于应变和黏聚区模型(CZM)建立了贴补复合材料层合板的渐进损伤分析模型,引入复合材料与胶层的损伤判据和刚度退化方案,计算了结构屈曲强度。数值仿真结果和实验数据吻合较好,验证了模型的有效性。基于该模型,采用非线性有限元方法研究了压缩载荷下双面贴补复合材料层合板的屈曲损伤演化过程,并讨论了补片参数对结构屈曲强度的影响。研究结果表明:双面贴补复合材料层合板屈曲后,处于拉伸和压缩状态下的铺层中的损伤程度存在差异;增大补片直径与厚度可以在一定程度上提高双面贴补复合材料层合板的屈曲强度。

Failure strength and damage evolution process of double-strap bonding repaired composite laminates under buckling compression are of great significance for composite structures repair.A progressive damage model based on strain as well as cohesive zone model（CZM）is developed for bonding repaired composite laminates.Failure criteria coupled with stiffness degradation schemes of composites and adhesive is used for damage initiation and propagation in order to predict the buckling failure strength.The numerical results show the consistency between the numerical results and experimental ones,which indicates that the proposed damage model is validated.Based on this model,the damage evolution process of repaired structures under buckling compression is studied using nonlinear finite element method.The influences of patch parameters on buckling strength are also discussed.The results indicate that damage status during loading on the tensile layers of laminates is different from that on the compressive layers;buckling strength of double-strap bonding repaired composite laminates can be improved with increasing patch diameter and thickness.