Time-dependent reliability analysis of corroded pipelines using a hybrid successive Pareto simulation and importance sampling approach

Resumo

The present study introduces a methodology for time-dependent structural reliability analysis of corroded pipelines by integrating the successive Pareto simulation (SPS) method with importance sampling (IS). This paper extends the application of SPS to assess the probability of failure evolution over time due to corrosion defects. First, the methodology is validated against results from the literature, where the DNV RP-F101 equation is applied. Then, the pipeline is modeled using a 2D axisymmetric finite element mesh automatically generated by using the PIPEFLAW software. Structural non-linear analysis is performed using the HYPLAS finite element code, considering failures due to small leak and burst. The reduction in the number of evaluations, compared to IS, is up to 34.52%. The hybrid SPS-IS approach improves the efficiency of reliability analysis for corroded pipelines by combining the lower number of function evaluations achieved by SPS with the variance reduction of IS.