Damage resistance analysis of composite laminates subjected to quasi-static indentation

A method of predicting the damage resistance of composite laminates subjected to quasi-static indentation was proposed. Damage variables were introduced to represent the matrix crack , delamination and fiber breakage , respectively , and stiffness degradation criteria were proposed for different damage modes. A progressive damage analysis was conducted for composite laminates under quasi-static transverse compressive loading by using a strain- based Hashin and Yeh failure criterion as well as the finite element method. The damage resistance was predicted. The numerical analysis was implemented with a commercial finite element code , ABAQUS/standard , via its user subroutine UMAT. The numerical results indicate that the onset and propagation of the delamination induce a discontinuity in the slope of the force-displacement curve , and the fiber breakages are induced once the contact force reaches its maximum. The numerical results agree well with the test data for the delamination onset load and the maximum contact force.