MICROMECHANICAL MODELING OF DAMAGE DEVELOPMENT IN POLYMER COMPOSITES

Damage initiation and progression in long fibre unidirectional continuous polymer composites has been studied at the microscale considering a three dimensional repeating unit cell (3D-RUC) with square packing consisting of a single fibre in a polymer matrix. Three damage modes under static loading have been looked at, viz., matrix damage, fibre failure and fibre-matrix debonding. A progressive damage model for the matrix, fibre breakage model using maximum stress failure criterion and interface debonding using a traction-separation criterion via cohesive zone modelling (CZM) approach has been implemented. Homogenization of the said 3D-RUC has been conducted for various load cases that describes the averaged response of the microstructure under combined progressive damage modes