Reliability analysis of a load-out support frame in offshore installations

Abstract

When an offshore platform topside is constructed in a yard, it should be loaded-out onto a transportation vessel. The load-out operations, however, involves many uncertainties, such as changing the load (weight of the topside platform) on the LSF or possible structural failures. The load on the LSF should be evaluated, as even a small failure in a structural member or a welding connection can lead to structural instability, or even catastrophic structural collapse. This study presents a newly developed method for analyzing the structural reliability of the LSF. The probability of failure is calculated by using AFOSM method assessment along with response surface methods. This proposed approach can provide a better understanding of safety requirements, so that the over-design of structures can be avoided. Furthermore, it can provide the coordinators of load-out operations with a better set of guidelines for determining the probability of failure during the load-out process.