Research of conditions of supporting underground pipeline and loads on protective coating

Abstract

During the construction and operation of underground pipelines, there is a need to develop projects for the engineering protection of insulation coatings from the mechanical effects of coarse soil. The task is most relevant with significant variability of the laying conditions along the length of the route. In particular, the difficult laying conditions include the passage of the route in the areas of distribution of rocky, gravelly and permafrost soils. The appropriateness of applying the methods of engineering protection of the insulation coating from mechanical stress should be justified both economically and in terms of technical and operational indicators. Therefore, the task of analyzing the conditions of support of the underground pipeline and the study of the created forces in the supporting part of the pipeline is very relevant and characterized by insufficient knowledge. The article analyzes the effect of bedding soil and backfill on the amount of force arising in the protective coating of the supporting part of the pipeline in the presence of unevenness of the base and its particle size distribution. The results of modeling the contact problem using models of a discrete (granular) medium at the base of the pipeline are presented. The wall thickness of the pipes affects the change in created force in the supporting part of the pipeline (for pipes are 1 420 mm the maximum difference is 22 %). In the presence of unevenness of the base, the force in the supporting part can increase by 3–5 times.