Buried pipelines can be subjected to differential ground movement events. The ground displacement field imposes geotechnical loads on the buried pipeline and may initiate pipeline deformation mechanisms that exceed design acceptance criteria with respect to serviceability requirements or ultimate limit states.The conventional engineering approach to define the mechanical performance of pipelines has been based on combined loading events for "in-air" conditions. This methodology is assumed to be overly conservative and ignores soil effects that imposes geotechnical loads and also provides restraint, on buried pipelines. The importance of pipeline/soil interaction and load transfer mechanisms that may affect local buckling of buried pipelines is not well understood.In this study a three-dimensional continuum finite element (FE) model, using the software package ABAQUS/Standard, was developed and calibrated based on large-scale tests on the local buckling of linepipe segments for in-air and buried conditions. The effects of geotechnical boundary conditions on pipeline deformation mechanism and load carrying capacity were examined for a single small diameter pipeline with average diameter to thickness ratio and deep buried condition. The calibrated model successfully reproduced the large-scale buried test results in terms of the local buckling location, pipeline carrying load capacity, soil deformation and soil failure mechanism.
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