Multi-scale modelling of the damage behavior for 3D woven composites with variant structure

In the process of fabricating a three-dimensional (3 D) woven perform, the variant structures introduced during adding and reducing tows, lead to changes of local tow orientation and woven pattern, which affects the mechanical response of 3 D woven composite. In this study, specimens with variant structure were manufactured by adding and reducing tow techniques, and representative unit cells of normal and variant structure were established by topological method. A multi-scale damage model was proposed to analyze the damage behaviors and predict the strength of 3 D woven composites with the user subroutine UMAT of ABAQUS/Standard. The results show that the variation of tensile modulus and strength between the experimental and simulation value were less than 4%. In addition, it is proved that the damage propagation of the macro-scale model with variant structure can be successfully captured.