Substantiated Risk Assessment of Jacket Structure

Abstract

We demonstrate a rational approach to structural reliability based on state‐of‐the‐art models. The risk of failure was calculated for a jacket structure in the Gulf of Mexico subjected to environmental loading. This was done both for one particular extreme hurricane that the structure survived and also for long‐term loading. Statistics of extreme loads were generated from a hindcast study. The fluid loading was calculated using well‐validated theories for the kinematics of extreme random waves and currents. Nonlinear pushover analysis was used to evaluate the ultimate strength of the structure. The likelihood of structural failure was predicted by calculating the probability that the environmental load would exceed the resistance of the structure. Physical uncertainty in the extreme environmental load and the resistance of the structure were included. These results and those from a previous analysis of a damaged structure match well with observations, corroborating the approach and its wider application.