Interaction of a rigid underground pipeline with elastic-viscous-plastic soil

Abstract

The results of numerical solutions of an axisymmetric two-dimensional problem of a rigid underground pipeline interaction with elastic-viscous-plastic soil are presented. The pipe-soil interaction begins when the underground pipeline moves in an axial (longitudinal) direction. The changes in velocity, displacement, shear stress, shear strains in the direction of the pipeline axis for fixed points of soil along the radial axis are obtained at a linear change in the given longitudinal velocity of the pipeline from zero to a certain constant value. An analysis of numerical results showed that the changes in the interaction force on the contact soil layer occur according to a two-link law with the manifestation of the peak value of shear stresses. When the pipeline moves at a constant velocity, the values of displacement over time increase, and the shear stress values remain constant. Obviously, at this stage, the Coulomb law is fulfilled. This result agrees with the results of known experiments. The obtained theoretical dependences of shear stresses on soil displacement relative to the underground pipeline reveal the formation mechanisms of the conditions for the underground pipelines - soil interaction. This result could not be obtained within the framework of the one-dimensional problem of the pipe - soil interaction.