Service Life Prediction for Longspan Overhead Crossing Pipe Bridge Based on Reliability Analysis

Based on stressed characteristics of pipe bridge structure itself,adopting complex Monte-Carlo sampling method and combined with finite element as well as a secondary development tool APDL. index parameters in sensitivity and failure probability of overhead crossing pipeline are analyzed and calculated. On the basis of analysis model for corrosion rate, yearly failure rate of structure at coaction of random parameters is analyzed. Taking some in-service pipe bridge as an example, its refiability is entirely analyzed. Calculation results show that the parameters closer to reliability index are main cable cross area, external pipe diameter and density of oil medium. Service life of the pipe bridge is forecasted based on allowable failure probabilities at different risk areas. Safe life of a pipe bridge at low risk area is up to 39 years, safe life of a pipe bridge at high risk area is up to 26 years.