Continuum damage mechanics based modeling progressive failure of woven-fabric composite laminate under low velocity impact

A continuum damage mechanics (CDM) meso-model was derived for both intraply and interply progressive failure behaviors of a 2D woven-fabric composite laminate under a transversely low velocity impact. An in-plane anisotropic damage constitutive model of a 2D woven composite ply was derived based on CDM within a thermodynamic framework, an elastic constitutive model with damage for the fibre directions and an elastic-plastic constitutive model with damage for the shear direction. The progressive failure behavior of a 2D woven composite ply is determined by the damage internal variables in different directions with appropriate damage evolution equations. The interface between two adjacent 2D woven composite plies with different ply orientations was modeled by a traction-separation law based interface element. An isotropic damage constitutive law with CDM properties was used for the interface element, and a damage surface which combines stress and fracture mechanics failure criteria was employed to derive the damage initiation and evolution for the mixed-mode delamination of the interface elements. Numerical analysis and experiments were both carried out on a 2D woven glass fibre/epoxy laminate. The simulation results are in agreement with the experimental counterparts, verifying the progressive failure model of a woven composite laminate. The proposed model will enhance the understanding of dynamic deformation and progressive failure behavior of composite laminate structures in the low velocity impact process.