Reliability assessment of the burst strength of corroded pipelines

Finite element simulations of intact and corroded pipes are carried out to derive an appropriate failure criterion considering the uncertainties of the input variables. The results are compared with the B31G and the modified B31G codes, which are used to assess the remaining strength of the pipes. The time dependent reliability is calculated for the three cases. A sensitivity analysis is performed to identify the influence of the various parameters on the probability of burst collapse of intact and corroded pipes. It is shown how the results of the reliability analysis can be used to ensure a constant reliability level throughout the life of the pipelines by decreasing appropriately the operating pressure as the corrosion level is increasing.