Progressive Failure of Composite Laminates; Analysis vs Experiments

The failure of composite structures divides into three stages; damage initiation, damage progression and final failure. A typical mechanism of damage initiation is matrix cracking in some layer of the laminate. Consequently, damage initiation is often referred to as the first ply failure (FPF). Damage progresses with several mechanisms that often occur interactively. Most important of these are additional matrix cracking and crack propagation, debonding of fibres and the matrix, and delamination of layers. The final failure typically takes place when the ultimate load carrying capability of the fibres is reached in some layer.