Abstract:
The soil-pipeline interactions in sand under lateral and upward movements are investigated with particular attention to the ultimate forces exerted on the pipe. The analytical solutions for estimating the ultimate forces are summarized and it is shown for the deep embedment condition that there is large uncertainty in the true values since the bounds established by the analytical solutions are large. In order to find the solution for the ultimate force and to investigate its transition from the shallow to deep failure mechanism, the finite element analysis of lateral and upward pipe movements is performed at different embedment ratios. Two different soil models are used for the simulations, i. e. Mohr-coulomb model and Nor-sand model. The accuracy of the analysis is first examined by simulating the experimental tank tests by trautmann & O'Rourke. The analysis is further extended to deeper embedment ratios of up to 100. The obtained FE results are used to construct a design chart for pipelines at deep embedment.