Lateral soil restraint of a buried pipeline

Numerical analyses have been carried out to simulate in situ pipe loading tests. These can improve the understanding of the behaviour of buried pipelines subjected to differential ground displacements. The numerical method adopted uses a two stage analysis technique. Stage 1 uses a finite element program to predict the restraining effect of the soil as a function of pipe displacement. These predictions are then used in stage 2 which simulates the load tests, employing an elastic beam on elastic foundation program. Results from full-scale loading tests on a transmission pipeline provide field data for validating the results of the numerical analysis. The results show that a proposed elasto-plastic model can adequately simulate soil restraint. Using this model and a “no tension” criterion, reasonable agreement between analytical and field results was obtained.