Effect Of Soil Resistance On Vertical Buckling Of Buried Pipelines

With the vigorous development of offshore oil industry, the application of the offshore pipeline is more and more widely. Those problems, which caused by the destruction of the pipeline, have caused great attention. Pipeline in operation process are commonly affected by ground motion and temperature load. Enough amount of temperature change, which can cause great axial stress to make the buckle of the pipeline. Eventually the pipeline will be destroyed. So first of all, this article has carried on the model test for loose sand under different embedment depth of pull-out force-displacement curve. Based on the experimental results, we has carried on the numerical calculation about the pipeline under different density of different buried depth of vertical buckling. The main content of the paper points the following parts:(1) The uplift experiment of pipelines buried in loose sand, which were divided into monotonous pull and circulation pull. In the process of drawing on, we observed the flow of sand soil and the process of the damage mechanism under monotonic load and circulation load by using PIV image recognition technology.(2) In this paper, we built a two dimensional numerical model of pipeline, using the finite element method, to analyze the influence of different soil binding on buried pipelines under the action of temperature vertical buckling. The pipeline model is able to simulate the elastic plastic and isotropic beam element, and the updated Lagrange equation is used. Based on the interaction between the pipeline and sand, the vertical buckling of buried pipeline under high temperature was studied. In the analysis of the pipeline buckling type, the submarine pipeline with some initial defects is discussed. The focus of this article is to focus on the effects of different types of soil springs on the buckling of pipelines subjected to temperature load.