Reliability analysis of steel pipe with longitudinal corrosion damage considering elastoplastic fracture behaviour

Reliability assessment on fracture failure of pipes due to corrosion has recently stimulated great interest in academia. However, a review of the literature suggests that little research has been conducted on prediction of steel pipe failure considering the ductile fracture characteristics. In this paper, a methodology is presented for predicting the time to corrosion-induced fracture failure of steel pipes with longitudinal damage based on elastoplastic fracture mechanics and the first passage method. The concept of J-integral and a generic form of stochastic model are employed to establish the load effect for the pipe with longitudinal corrosion damage. To facilitate practical application of the proposed methodology, a worked example is presented with sensitivity analysis to identify the most influential factors for fracture failure. It is found in the paper that fracture failure contributes to the probability of pipe failure more than leakage failure mode. It is also found that reference stress in the J-integral model, the diameter of the pipe, the fracture resistance of steel and the corrosion growth rate are the dominant factors for fracture failure. The methodology presented in this paper can serve as a rational tool for pipeline engineers to develop rehabilitation or maintenance strategies.