EXPERIMENTAL AND NUMERICAL INVESTIGATION ON UPHEAVAL BUCKLING OF FREE-SPAN SUBMARINE PIPELINE

Submarine pipeline is widely used for the transportation of oil and gas in offshore exploration and production. The free span of pipeline is inevitable because of the complex seabed conditions, which may result in the upheaval buckling failure under the service conditions. In this paper, several experimental tests on scale models of submarine pipelines was carried out. The test results show that the length of the free span is closely related with the buckling of the pipeline. The upheaval buckling of pipelines is induced by the high compressive stress due to thermal action and triggered by the initial curvature due to self-weight. Thus, the traditional analysis and design method with effective length method cannot be used. Based on the experimental results, a simple and effective finite element model is developed and verified for parametric study. The numerical simulation results show that the diameter, length of free span and the self-weight of the pipeline will influence the buckling resistance of the pipeline system. The proposed finite element model can be used for the practical design of submarine pipelines. Copyright (C) 2019 by The Hong Kong Institute of Steel Construction. All rights reserved.