From bi-dimensional discrete model to anisotropic damage model: a feasibility study

This study investigates using a discrete model (explicitly representing micro-cracking) as a "virtual test machine". Anisotropic damage models often require complex experiments to be formulated and identified. Discrete models could reduce the experimental cost of formulating an anisotropic damage model. A beam particle model represents a 2D square specimen of quasi-brittle material in this work. A damaging loading is applied to the specimen until the localization of micro-cracking. The evolution of the effective elasticity tensor is measured at each load step through elastic loadings. The measurement procedure is then illustrated with a tensile loading. Harmonic decomposition is used to analyze this evolution. The analysis of the evolution highlights the correlation between micro-cracking and stiffness loss. Additionally, calculating distances to symmetry classes allows quantifying anisotropy induced by micro-cracking. Eventually, it will provide a means to build an anisotropic damage model based on harmonic decomposition.