Effects of Oblique Incident P-Waves on the Seismic Response of a Buried Pipeline With Double Corrosion Defects in Permafrost Regions

Abstract

Abstract. This study focuses on X80 pipelines and establishes a three-dimensional pipe–soil interaction model in abaqus. Based on wave theory, the loading of obliquely incident P-waves in the finite element model was implemented, and the effects of temperature, corrosion spacing, and incident angle on the stress, acceleration, and displacement responses of the pipeline were analyzed. The results indicate that at +0 °C, the stress response of the pipeline increases significantly due to the reduction in seismic wave velocity caused by the decrease in soil elastic modulus. When the axial spacing between double corrosion defects exceeds 4 times the wall thickness, the interaction between them becomes negligible. The stress response of the pipeline first increases and then decreases with the increase of the incident inclination angle (θi), while it continuously increases with the increase of the incident azimuth angle (θv). The most severe stress response and the highest safety risk occur when θi = 60 deg and θv = 90 deg. Additionally, the incident azimuth angle has a minor impact on the vertical acceleration and velocity of the pipeline but significantly affects the lateral and axial responses. In contrast, the incident inclination angle noticeably influences the acceleration and velocity responses in all three directions of the pipeline, with the most pronounced effect observed at θi = 60 deg.