Damage tolerance of laminated tee joints in FRP structures

Abstract

This paper is concerned with the damage tolerance of laminated tee connections in large fibre reinforced plastic (FRP) structures found in marine construction. Such connections represent a potential zone of weakness in ships and it is essential that their mechanical behaviour is well characterised. Previous work has focused on static as well as fatigue behaviour. There is growing evidence that delamination induced damage in the root of the tee is a potential source of catastrophic failure as well as being expensive in repair terms. The paper briefly outlines the load transfer mechanisms in single skin tee joints under representative boundary conditions and establishes the failure inception and damage progression under static loading. Numerical analyses are then presented to link the observed failure scenarios to stress levels in different parts of the tee. Lastly, a fracture mechanics approach is used to identify the seriousness of a particular delamination vis-a-vis ultimate failure.