A SEMI-ANALYTICAL CONTINUUM DAMAGE MECHANICS MODEL FOR VARIABLE ANGLE TOW COMPOSITE LAMINATES

In this work, a Ritz formulation for the analysis of damage initiation and evolution in variable angle tow composite plates under progressive loading is presented. The formulation is based on the first order shear deformation theory with von Kármán assumptions and includes the effects of material damage and energy dissipation. The onset of damage is predicted using Hashin's criteria, and a linear softening law is used to describe the degradation of the constitutive relations. The governing equations are obtained by applying the principle of minimum potential energy and using orthogonal polynomials for the approximation of the primary variables. An adaptive multi-domain discretization is introduced to avoid the Gibbs effect and to represent the global response of the structure as a piecewise continuous function. Numerical results are presented to demonstrate the effectiveness of the proposed method in predicting the response of composite structures under different loading conditions and highlight some issues to be addressed by suitable developments of the method.