Centrifuge and numerical modeling of moving traffic surface loads on pipelines buried in cohesionless soil

The main aim of this research was to investigate the mechanism of deformation of buried pipe under traffic moving load and the suitability of the modified Spangler-Iowa formula, coupled with the Boussinesq theory of load transmission through elastic media in predicting the deformation of these buried structures. This study employed reduced-scale physical model tests in a geotechnical centrifuge, numerical back-analysis using ABAQUS software and a numerical prediction for a hypothetical case. The hypothetical case consisted of a steel pipe buried in cohesionless soil under moving surface loads. Nine centrifuge tests were carried out for three different embedment ratios in dense, medium and loose sand. The tests results demonstrated that the formulas used for pipeline projects, the modified Spangler-Iowa formula together with the Boussinesq theory, are somewhat conservative for all densities analyzed and that the degree of conservatism increases with both embedment ratio and with the stiffness of the soil the pipe rests.