Corrosion failure probability simulation of directly buried heating pipeline

To analyse failure probability of heating pipeline, according to the force analysis of directly buried heating pipeline, based on generalized stress-strength interference theory, establishes the limit state equations of four failure modes for pipeline which are strength failure, vertical instability, radial instability and local buckling.Studies the failure probability of heating pipeline caused by corrosion using power function corrosion rate model. According to the stochastic characteristics of the relevant factors, simulates the stress state of heating pipeline by the Monte Carlo method.Determines the safe and failure states of the pipeline by the limit state equation. Obtains the failure probability by dividing the total number of failure events with the total simulation times.The simulation results of DN1000 heating pipeline show that the strength failure is the main failure mode of the directly buried heating pipeline, the growth rate of pipeline failure probability accelerates at first and then slowdowns in severe corrosion environment, and when water temperature exceeds 120 ℃, the pipeline failure probability rises quickly and the average growth rate reaches 5.21×10-2/℃.