Behavior Of Buried Pipes Exposed To Longitudinal Permanent Ground Deformations In Earthquakes

Abstract

Observations from past earthquakes have shown that pipes are more adversely affected and damaged by ground movements, particularly in the direction of their long axis. Based on this observation, the present study evaluates buried continuous pipelines exposed to ground movement in the direction of the pipe due to earthquakes. Numerical analysis was conducted using the finite element method. Commonly used types of steel pipes in natural gas lines were selected for the analysis, with pipe diameter, mechanical properties of the pipe, burial depth, soil-pipe friction, and ground movement values considered as variable parameters. Additionally, eight different geometrical layouts of the pipes, depending on the condition of the roads and existing structures, were evaluated. The behavior of these pipelines under the influence of permanent ground movements (ranging from 0.01 to 4 meters) was determined for different pipe placement situations. The analysis yielded results for displacements, tensile and compressive deformations, and tensile and compressive stresses in the pipeline. The effects of the varying parameters on the pipe were also determined. The study's results illustrate the behavior of buried steel pipes under different permanent ground movements caused by earthquakes and contribute to the design and preliminary evaluations of buried pipelines by the operating institutions. © 2025 Gazi Universitesi. All rights reserved.