Parametric study on the trench designing for X80 buried steel pipeline crossing oblique-reverse fault

• Published in: Soil dynamics and earthquake engineering (1984) 2021-11, Vol.150, p.106824, Article 106824
• Main Authors: Cheng, Xudong, Huang, Runkang, Xu, Lingyue, Ma, Chuan, Zhu, Xingji
• Format: Article
• Language: English
• Subjects: Backfill; Buckling; Buried pipes; Critical fault displacement; Design; Design parameters; Earthquakes; Failure; Gas pipelines; Gas transmission; High strength low alloy steels; Mathematical models; Natural gas; Numerical models; Oblique-reverse fault; Optimal scheme; Parametric statistics; Petroleum pipelines; Pipeline design; Pipeline trench design; Pipelines; Seismic activity; Seismic design; Soils; Steel pipes; Three dimensional models; X80 buried steel pipeline
• ISSN: 0267-7261; 1879-341X
• DOI: 10.1016/j.soildyn.2021.106824

The safety operation of buried long-distance oil and gas pipelines has long been threatened by the active fault movement due to earthquake. In this paper, a three-dimensional numerical model of X80 buried pipeline crossing oblique-reverse fault was established considering the existence of pipeline trench and backfill soil. The values of parameters were derived from the Third West-to-East Natural Gas Transmission Pipeline Project in China. The strain development and deformation features of pipeline for local buckling and tensile fracture were obtained. The influence of various trench design parameters (pipeline burial depth, trench slope inclination, backfill soil type and thickness) on the failure process was discussed. Meanwhile, based on the failure criterion of buried pipelines, the critical fault displacements corresponding to different trench design schemes were studied. It is shown that the failure of pipelines can be avoided by reasonable trench design in the areas of low seismic intensity. Finally, the optimal scheme was further given to provide a reference for the seismic design of buried pipelines at oblique-reverse fault crossings. •A 3-D numerical model considering the role of pipeline trench backfill is proposed.•The effects of pipeline trench geometric size and backfill soil properties on the strain development of buried pipeline subjecting to oblique-reverse faulting are studied.•The seismic performance of buried pipeline under different trench design schemes are obtained, and a optimal trench design scheme is further presented.