A multiscale strategy for assessing the micro-scale stress distribution in the matrix of textile composites

In this work, a multiscale strategy for estimating the local stress fields in the matrix of woven composites is presented. This is a fundamental tool for predicting the static and fatigue bundle crack initiation. The strategy adopts first an analytical model to estimate the average stresses in the bundles at the meso-scale. These are used as an input for 2D Finite Element (FE) analyses on representative volume elements to calculate the local stress fields in the matrix at the micro-scale. In particular, the cumulative distribution function of the local stress components in the matrix are predicted. From that, the average stresses in a control volume of the matrix are obtained, to be used for assessing the crack initiation in off-axis bundles. The entire strategy is validated experimentally, in terms of elastic properties, and numerically, in terms of average bundle stresses and local stress fields obtained through full 3D FE analyses.