Effect of Ground Stack for Additional Internal Force and Deformation of Underground Pipeline

Abstract

Based on a three-dimensional finite element model of an underground pipeline, the influence of additional ground loads on the stress characteristics of the pipeline was studied. Furthermore, the effects of different soil properties, load locations, and varying burial depths on the pipeline’s stress characteristics were analyzed. The research results show that as the distance between the load center and the pipeline axis increases, the positions of the pipe’s maximum displacement, bending moment, and shear force along the axis decrease significantly. However, when this distance reaches a certain value, the pipeline’s maximum vertical displacement and internal forces approach zero. Different pipelines exhibit minimum values of maximum axial displacement and vertical displacement in soft soil, while maximum axial displacement occurs in clay, and the largest vertical displacement is observed in sandy soil. The maximum axial displacement of UPVC pipes in clay is twice that of soft soil. The vertical displacement of pipes made from different materials increases with burial depth, but for concrete and steel pipes, the maximum axial tension increases significantly with depth, whereas the change in UPVC pipes is more gradual.