Reliability evaluation of local corrosion of X80 pipeline subjected to accidental earthquake considering geotechnical discontinuities

Highlights: • Establish nonlinear FE dynamic model about typical spatiotemporal evolution of X80 corrosion pipelines. • Investigation of the performance-based failure pressure of corrosion pipelines subjected to earthquake. • Embed the ILI-based corrosion stochastic model into FEA model to infer future possible SDLS. • Developed discreted spatiotemporal analysis to evaluate system reliability. Local corrosion poses a big threat to the integrity and safety of steel pipelines. Investigation of the failure pressure of buried pipelines containing multiple corrosion defects subjected to earthquakes is vital for pipeline safety. In-line inspection (ILI) data is introduced to estimate and update the 3D random corrosion growth model, embedded in the development of a nonlinear finite element analysis (FEA) model of the X80 pressure pipeline. The novelty of this work lies in the development of a nonlinear FE dynamic model for the typical spatiotemporal evolution of corroded pipelines considering vertical heterogeneous soil structure, which further implements performance-based reliability assessment. The system reliability is estimated by combining the improved equivalent component approach (IECA) and extreme value theory (EVT). Numerical studies illustrate that the proposed model is feasible for corroded pipelines under an earthquake to execute a multi-failure mode reliability assessment to find the possible failure pressure.