A multiscale progressive damage analysis for laminated composite structures using the parametric HFGMC micromechanics

A nonlinear multiscale damage analysis is proposed based on the parametric High Fidelity Generalized Method of Cells (HFGMC) micromodel. Two repeating unit-cells (RUCs), square and hexagonal, for the composite microstructure are discretized into subcells which represents the fiber and matrix phases. Average traction and displacement continuities, periodicity conditions, and volumetric equilibrium are applied. The proposed modeling approach is implemented as a user material subroutine within displacement-based layered-shell FE models, where each layer can be represented with at least one RUC. The RUC through-thickness stress and stiffness contributions are eliminated in case of a failure. Two failure criteria, in conjunction with compressive strength equation, are applied to determine RUC failure. In the first, the Tsai-Wu failure criterion is used at the RUC level. The second employs the strain invariant failure theory (SIFT) within each subcell, leading to its extinction. The in-situ properties and damage parameters of the RUC are determined by calibration using axial, transverse, and shear data of unnoteched laminates. The accuracy of the proposed framework is demonstrated by a comparison with experimental results of open-hole laminates.