ABSTRACT
Damage stress analysis of composite structures is based on the stress state around the damaged area. The stress state analysis will include the influential aspects, such as stress concentration development, environmental degradation of mechanical properties, damage location, damage orientation and damage complexity. The estimated stress state is then compared with the component’s ultimate strength or the first ply failure strength or the design limit stress state to determine the severity of the damage. This approach to damage stress state estimation is typically conservative, especially when considering the current material load performance requirements. However, the damage stress state estimation will provide the engineer with an indication of what type of repair scheme needs to be designed. For example, there is a cosmetic repair scheme for environmental exclusion, or a semi-structure repair scheme for damage tolerance restoration, or a structural repair scheme for restoration of structural integrity, if needed.
