A simplified micromechanics model for predicting the stiffness degradation in symmetric composite laminates

Recently, the authors of this paper have developed a new micromechanics approach to evaluate the stress fields and material properties of an orthotropic composite ply containing specified matrix cracking density under multi-axial loading condition. In this study, more complementary details of approach are obtained, and a closed form solution for evaluating the stress fields and stiffness degradation of a damaged ply will be presented and applied for analysing several composite laminate with general symmetric lay-ups. The obtained results will be compared with the available experimental results. The major advantage of the mentioned micromechanics approach is its capability for analysing an arbitrary composite ply containing specified matrix crack independent of its adjacent plies. This preference can be applied for bridging the proposed micromechanics model into the finite element analysis for progressive modelling of matrix cracking in general symmetric laminates with the least computational effort and the most accuracy.