In this paper a reliability analysis of a Mono-tower platform is presented. The failure modes, considered, are yelding in the tube cross-sections, and fatigue failure in the butt welds. The fatigue failure mode is investigated with a fatigue model, where the fatigue strength is expressed through SN relations. In determining the cumulative fatigue damage, Palmgren-Miner's rule is applied. Element reliability as well as systems reliability is estimated using first-order reliability methods(FORM). The sensitivity of the systems reliability to various parameters is investigated. It is shown for the fatigue limit state is a significant failure mode for the Mono.tower platform. Further, it is shown for the fatigue failure mode the the largest contributions to the overall uncertainty are due to the damping ratio, the inertia coefficient, the stress concentration factor, the model uncertainties and the parameters describing the fatigue strength.
|Series||Fracture and Dynamics|
PDF for print: 20 pp.
- Fatigue Failure
- Fatigue Damage