OPTIMAL INSPECTION SCHEDULE FOR FATIGUE CRACKS IN OFFSHORE STRUCTURES

In this paper a criteria for optimal fatigue inspection scheduling is proposed and applied to an offshore platform in Mexico. The formulation includes the estimation of structural reliability and life-cycle costs associated to a particular inspection schedule. Both estimations are performed considering the potential occurrence of fatigue cracks on the whole platform not just for a particular joint. The structural reliability is based on a fracture mechanics model and the costs correspond to the failure and inspection and repair events as they may occur during the life of the structure. The application involves the specific costs, structural properties, environmental loading and inspection and repair practices as used in Mexico