Elastoplastic Analysis of Mechanical Response of Buried Pipelines under Strike-Slip Faults

Abstract

A two-dimensional elastoplastic analytical model of stress–strain analysis of the pipeline under strike-slip faults was established based on the plastic flow theory and elastoplastic-beam theory, considering the effects of service loads and the nonlinearities of the pipeline and the pipe–soil interaction. According to the plastic flow theory, the axial, radial, and hoop plastic strains were derived, and the stress–strain relation was established under the plane stress state. The axial stress and strain of the pipeline induced by fault displacements were analyzed based on the elastoplastic beam theory. Additionally, the axial stresses, hoop stresses, and strains induced by the service loads (i.e., the internal pressure and the temperature variation) were also considered. The proposed model was verified by comparing the analytical results and the finite-element results. The results show that the proposed model can predict accurately the mechanical response of the pipeline subjected to strike-slip fault displacements, with minor deviations of within 10%.