Advancing pipe–soil interaction models in calcareous sand

The interpretation of geotechnical centrifuge experiments of a segment of pipe on calcareous sand is described. Results of 33 individual tests are used to advance a theoretical plasticity model that describes the load–displacement behaviour of a pipe when subjected to combined vertical and horizontal loading. A new model formulation is provided with all parameters calibrated from the experimental tests. It is shown that the modified model provides excellent agreement with the centrifuge data up to lateral displacement of two pipe diameters. This provides additional confidence in its use in the simulation of long pipeline events. The principal purpose of the model is illustrated in a numerical example calculation of the response of a 1245 m long pipeline. Integrating the model into a structural analysis program allows efficient modelling of the pipe–soil behaviour, as demonstrated for the partially buried pipe subjected to 3 h of storm loads.