Abstract:This paper established analytical model of pipe-soil system under freezing-thawing, conducted thermo-mechanical coupling analysis of the system under fault movement, and investigated the strain developing law. Different soil stiffness at different temperatures, leads to different pipe-soil interaction and different strain development laws of the pipe under fault movement. By comparing the numerical results of the force field under the real temperature field and the simplified temperature field, it is found that the strain law corresponding to the two temperature fields is quite different, and the local buckling of the pipeline is obviously earlier than the tensile failure. It is recommended that for the buried pipeline across the frozen soil fault, it is necessary to obtain the true pipe-soil temperature field by finite element simulation considering the temperature of the soil ground and pipe fluid, and then adopt the strain under fault movement for the seismic design or checking computation.