Simulation of Composite Laminate with Cohesive Interface Elements Under Low-Velocity Impact Loading

In this paper, numerical model based on continuum damage mechanics is presented to predict the damage behavior in quasi-isotropic composite laminates under low-velocity impact conditions. Hashin criterion and a gradual degradation scheme are employed to trigger the intra-laminar damage initiation and growth. Additionally, an interface cohesive element is incorporated in the model to predict the inter-laminar delamination damages. A user-defined subroutine VUMAT comprising these constitutive models of intra-laminar and inter-laminar damage is written in FORTRAN and implemented into explicit finite element package ABAQUS. Parametric analysis is performed on quasi-isotropic composite model with different impact energy levels to study the impact velocity-time, velocity-displacement, acceleration-time and acceleration-displacement curves of full and reduced models as well as the damage development of intra-laminar matrix cracking and inter-laminar delamination. Reasonable accord between the numerical simulations and experimental test indicates good prediction of impact damage behavior of the proposed model at low-velocity impact conditions.