Congress on Civil Fragility Surface Assessment to Evaluate Corrosion Defects Interaction Effect on Offshore Pipelines Reliability

Internal corrosion significantly threatens the structural integrity of offshore pipelines. This study employs the Finite Element Method (FEM) to evaluate the reliability of internally corroded offshore pipelines by considering the interaction of multiple corrosion defects. The FEM analysis was conducted using ABAQUS software, with Python scripts facilitating large-scale modeling, and the input database was generated using Latin Hypercube Sampling (LHS). The reliability of ۳۲-inch oil and gas offshore pipelines has been assessed through fragility surface evaluation. Four two-parameter probability density functions— normal, lognormal, Weibull, and gamma-were fitted to the Maximum Von Mises Stress (MVMS) data at varying internal pressures (IP) and longitudinal spacing (SI) levels. Fragility surfaces, developed using lognormal cumulative distribution functions (CDFs), illustrate the probability of MVMS exceeding critical thresholds at different IP and Sl levels. The findings reveal that defect interaction can significantly increase the probable MVMS, affecting pipeline reliability. The fragility surface representation provides valuable insights into the probabilistic behavior of corroded offshore pipelines, aiding in integrity management and risk assessment.

کلیدواژه ها:

Pipeline ، Reliability ، Random Sampling ، LHS ، Fragility