ANISOTROPIC DAMAGE IN COMPOSITE SHELL STRUCTURES

Abstract

CONTINUUM DAMAGE MECHANICS (CDM) HAD IMPORTANT DEVELOPMENTS SINCE THE INITIAL WORKS OF KACHANOV AND RABOTNOV, AND CONSTITUTES NOW A PRACTICAL TOOL TO ACCOUNT FOR MACROCOSPIC DAMAGE IN MATERIALS AND STRUCTURES. IN THIS WORK, AN APPLICATION OF THE ANISOTROPIC DAMAGE THEORY BASED IN MURAKAMI WORK IS PRESENTED. IN THE PRESENTED FORMULATION, THE FOURTH ORDER DAMAGE TENSOR M (THAT RELATES CAUCHY AND EFFECTIVE STRESS TENSORS) IS DETERMINED ON THE BASIS OF THE TENSOR ­ (THREE-DIMENSIONAL AREA DENSITY OF DAMAGE) THAT, IN TURN, CAN BE DETERMINED THROUGH EXPERIMENTAL DATA. THE ANALYTICAL FORMULATION IS SET IN INCREMENTAL FORM AND IMPLEMENTED INTO A ¯NITE ELEMENT PROGRAM (FOR PLATES AND SHELL STRUCTURES IN COMPOSITE MATERIAL) TAKING ACCOUNT OF GEOMETRICALLY NON-LINEAR EFFECTS. IN ORDER TO VERIFY AND VALIDATE THE NUMERICAL MODEL, COMPARISONS BETWEEN ANALYTICAL AND EXPERIMENTAL RESULTS FOR SIMPLE SITUATIONS ARE PRESENTED.