Continuum description of damage and failure of composite laminates based on viscous regularization

Purpose - The purpose of the paper is to improve the calculability of a continuum damage failure model of composite laminates based on Tsai-Wu criteria. Design/methodology/approach - A technique based on viscous regularization, a characteristic element length and fracture energies of fiber and matrix are used in the model. Findings - The calculability of the material model is improved. The modified model can predict the behavior of composite structure better. Originality/value - The convergence problem and the mesh softening problem are main concern in the calculability of numerical model. In order to improve the convergence, a technique based on viscous regularization of damage variable is used. Meanwhile, characteristic element length and fracture energies of fiber and matrix are added into the damage constitutive equation to reduce the mesh sensitivity of numerical results. Finally, a laminated structure with damages is implemented using a User Material Subroutine in ABAQUS/Standard. Mesh sensitivity and value of viscosity are discussed.