An investigation into pipelines subjected to lateral soil loading

• Main Author: Paulin, Michael J.
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 1998
• Subjects: permafrost
• Online Access: https://research.library.mun.ca/8587/; https://research.library.mun.ca/8587/1/Paulin_MichaelJ.pdf

With the increased use of pipelines for carrying gas, oil, water, and electrical cables, the response of the pipeline to soil movements in the vicinity of the pipeline needs to be understood. These movements may be due to adjacent earth works, landslides, thaw settlement of permafrost, frost heave or a variety of other causes. These soil movements set up stresses within the pipeline and, depending upon the magnitude of these stresses and the nature of the pipeline, may cause damage to or failure of the line. Several consequences may be associated with pipeline failure and include loss of life, damage to the environment, and economic costs. The stresses which are generated by the soil movements are dependent upon a number of parameters, which include the nature of the soil, the properties of the pipeline, and the geometry of the pipeline/soil/backfill system. -- The state-of-practice (SOP) for pipeline design for areas where soil may move relative to the pipeline involves discretizing the pipeline into elastic-plastic segments which are connected to sets of springs/sliders which simulate the soil. As the springs replace the soil, their force-displacement characteristics should correspond to the actual soil response if a meaningful analysis is to be conducted. Much of the theory behind the interaction parameters used in the SOP are derived from theories developed for other geotechnical applications such as pile/soil or anchor plate/soil interaction; there is little or no verification of the mechanisms or the magnitude of forces which arise during pipeline displacement. This thesis presents a research program conducted to examine one aspect of pipeline/soil interaction; that of lateral pipeline/soil interaction. -- The objectives of the research program outlined in this thesis were to: (1) conduct physical model testing of lateral pipeline/soil interaction in cohesive soil to ascertain the effects of trench width, burial depth, interaction rate, backfill properties, and stress history of the soil on the interaction ...