Influence processes freezing and thawing of permafrost soils on underground pipeline’s stress-strain state

Abstract

The positions of the underground routing pipeline under conditions of the effect of the freeze-thaw processes in the permafrost soils are simulated in the paper. The change in seasonal temperatures leads to the emergence of thermokarsts, heaving and soil failures along the oil pipeline route, which negatively affects the performance of the object. The paper presents the calculation of 520 mm outer diameter (355 JR steel), 30 m length oil pipeline of underground routing (1.5 m depth of burial) in the permafrost soil conditions, which runs 25 ⁰C temperature oil under 5 MPa pressure, with 0 ⁰C temperature pipe casing. Modeling carried out in SolidWorks software using Simulation package. The stress-strain state and travels occurred during the seasonal changes in the soil are determined. According to the results of the study, the methods of reducing the influence of freezing and thawing processes to prevent the negative impact of mm soils on the oil pipeline are proposed.