基于渐进损伤模型的复合材料斜接接头的拉伸强度

Parametric Study on the Tensile Strength of the Composites' Scarf Joint Using Progressive Damage Model

本文首先以斜接角度、搭接长度以及搭接厚度为参数分别建立了复合材料单边斜接接头和双边斜接接头在拉伸载荷下的参数化有限元模型,采用abaqus软件中UMAT子程序功能编写了材料损伤本构模型,并利用cohesive单元模拟胶接界面损伤。通过渐进损伤分析,模拟出斜接接头的三种破坏模式,最终得到了各参数变化对斜接接头拉伸强度的影响,其中母板最终破坏模式对应最大拉伸强度,并对单边斜接接头和双边斜接接头结果进行了对比分析,得出双边斜接接头强度大于单边斜接接头强度的结论。

Parametric models were proposed for both unilateral and bilateral scarf joints of the composites under tensile load,in which the parameters were scarf angle,overlap length and overlap thickness.The damage constitutive equation for the composites was established by the UMAT subroutine.The damage of the bonded interface was simulated by the cohesive element method.Through the progressive damage analysis,the three failure modes of the scarf joint were simulated,and the impact on the tensile strength was accessed by changing various parameters,in which ultimate failure mode of the parent structure was determinative to the tensile strength.By the comparison,it is concluded that the bilateral scarf joint has higher strength than the unilateral scarf joint.