A methodology for time-varying resilience quantification of an offshore natural gas pipeline

Abstract

Many resilience definitions and metrics have been presented across various disciplines in recent times. However, from a design and operations perspective, a limited effort is focused on quantifying the resilience of oil and gas support structures. This study proposes a methodology for structural resilience quantification of an offshore hydrocarbon pipeline. Resilience is modelled as a function of the structure’s time-dependent reliability, adaptability, and maintainability. The proposed model is demonstrated on an internally corroded offshore natural gas pipeline segment with multiple initial defects; and considers disruptive events arising from the leak, burst, and rupture failure modes. The resilience index and sensitivity analysis are evaluated for the offshore pipeline. The pipeline sensitivity analysis indicates the apparent effect of pipe wall thickness and defect depth growth rate on resilience over its design life. The outcome of this study provides an insight into the resilience quantification of structural systems considering multiple disruptive events. The proposed model is expected to serve as an essential tool for resilience evaluation during the design and operations of oil and gas structures.