Optimum and Minimum Acceptable Reliability Indexes for Mooring Lines Design in FPSO Systems

Authors

Roberto Montes-Iturrizaga, Ernesto Heredia-Zavoni, Daniel Straub and Michel H. Faber

Abstract

We present a risk-based methodology to define optimum and minimum acceptable reliability indexes for mooring line design for FPSO systems. The ultimate limit state (ULS) under extreme environmental events is considered. A Bayesian Network (BN) is employed for computing the expected failure costs given failure of a single mooring line, taking into account all possible scenarios with respect to the mooring system and the entire FPSO. The optimum reliability is then determined by minimizing the total expected cost. The minimum acceptable reliability index is established from a criterion based on the Life Quality Index (LQI) and the cost of mitigating risks to personnel.

Published in/by

Proceedings, IFIP'08 WG7.5 Working Conference, Mexico City, Mexico, August 6-9, 2008.