Studies on the Performance of Pipelines Subjected to Differential Settlements: Numerical Study

Abstract

AbstractThis paper details the mechanical behaviour of buried steel pipelines crossing differential settlement zones. The investigation is based on numerical simulation of the non-linear response of the pipeline-soil system, through the finite element method. The numerical simulation considers geometric (large strain and displacement), material (non-linear material behaviour of soil and pipeline) and boundary (interaction between buried pipeline and the surrounding soil) non-linearities. The effects of parameters, like diameter to thickness ratio, embedment depth and internal pressure, friction coefficient, settlement rate and soil properties on pipeline behaviour, are investigated in terms of cross-sectional distortion, axial tensile and compressive strain. The results show that the maximum strain appears on both side of the settlement section in the pipeline. In ground settlement zone, the axial strain on the top of the pipeline is compressive strain and axial strain on the bottom of the pipeline is tensile strain, reverse behaviour is observed in the no settlement zone of pipeline. The results from the present study can be used for the development of a performance envelope, which can be used for better design of pipelines.KeywordsPipelineSoil settlementNumerical modellingDifferential settlements