Assessment model of pipe soil interaction during large-amplitude lateral displacements for deep-water pipelines

The controlled buckling design of deep-water pipelines requires comprehensive understanding of pipe-soil interactions subject to large-amplitude lateral displacements. This paper explores this issue using a large displacement sequential limit analysis (SLA) method. The elevation of the pipe invert is kept constant during the lateral displacement to consider the situation when strong constraints from adjacent sections (e.g. intermittent rock dampers, anchors, etc.) are present and the validity of the numerical model is demonstrated by comparisons with five published high-quality centrifuge tests. Parametric studies on the effects of pipe embedment and strength profile are performed, leading to the development of analytical models to predict both lateral and vertical soil resistances during lateral displacement. The evolution of V-H yield envelopes, if presented in a normalised form, is found to be independent on the lateral displacement and can be satisfactorily captured by a binomial equation model.