Mechanical Behavior Analysis of the Buried Steel Pipeline Crossing Landslide Area

Abstract

Landslide movement is one of the threats for the structural integrity of buried pipelines that are the main ways to transport oil and gas. In order to offer a theoretical basis for the design, safety evaluation, and maintenance of pipelines, mechanical behavior of the buried steel pipeline crossing landslide area was investigated by finite-element method, considering pipeline-soil interaction. Effects of landslide soil parameters, pipeline parameters, and landslide scale on the mechanical behavior of the buried pipeline were discussed. The results show that there are three high stress areas on the buried pipeline sections where the bending deformation are bigger. High stress area of the compression side is bigger than it on the tensile side, and the tensile strain is bigger than the compression strain in the deformation process. Buried pipeline in the landslide bed with hard soil is prone to fracture. Bigger deformations appear on the pipeline sections that the inside and outside lengths of the interface are 30 m and 10 m, respectively. The maximum displacement of the pipeline is smaller than the landslide displacement for the surrounding soil deformation. Bending deformations and tensile strain of the pipeline increase with the increase in landslide displacement. Bending deformation and the maximum tensile strain of the pipeline increase with increasing of the soil's elasticity modulus, cohesion, and pipeline's diameter–thickness ratio. Soil's Poisson's ratio has a great effect on the displacement of the middle part, but it has a little effect on other sections' displacement.

Mechanical behavior analysis of gas pipeline with defects under lateral landslide

“…However, due to technical reasons, this research adopts the method of force driven pipeline offset, but in the actual landslide process, the interaction between soil and pipeline will be very complex, so the results obtained by this method are quite different from the actual. Zhang et al 10 used the finite element method to study the mechanical behavior of buried steel pipeline crossing landslide area, considering the pipe soil interaction. The effects of landslide soil parameters, pipeline parameters and landslide scale on the mechanical properties of buried pipelines are discussed.…”

Detection and Numerical Simulation of Potential Hazard in Oil Pipeline Areas Based on UAV Surveys

“…Establishing a slope-pipe coupling finite element model to analyze slope stability and pipeline stress and deformation is a widely used method in current research (Han et al, 2012;Li et al, 2016;Zhang et al, 2016;Mamuzo Edeki, 2020). As the UAV monitoring data cannot directly and quantitatively analyze the influence of unstable slope on the deformation of the pipeline body, this study is based on the strength reduction method and adopts the slope-pipe fully coupled finite element model to carry out multi-scenario simulation from stable state to unstable state.…”

“…By assuming that the pipeline is a buried beam model, a soil spring model, or an inelastic contact model to consider the interaction between the pipe and the soil, the displacement and stress distribution characteristics of the pipeline under different crossing modes (such as transverse, longitudinal, and diagonal) have been fully explained (Di Frisco et al, 2004;Cocchetti et al, 2009a,b). On this basis, considering the influence of slope structure parameters (slope width, slope, and displacement) and pipeline process parameters (burial depth, diameter-thickness ratio, internal pressure) on the mechanical characteristics of the pipeline, and expanding the multi-condition finite element method simulation, the effect of slopes on pipelines has been discussed in a more comprehensive and detailed manner (Lollino et al, 2010;Zhang et al, 2016Zhang et al, , 2018. After mastering the law of pipe mechanics response, the research work gradually turned to the prediction of pipeline safety, such as: discussing the maximum safe length of the pipeline under the above-mentioned multiple working conditions, proposing a prediction formula for the maximum stress of the pipeline, and using actual monitoring data to verify related reliability of conclusions (Ishii et al, 2012;Luo et al, 2014;Li et al, 2016;Vasseghi et al, 2021).…”

Response analysis of the nodes of pipe networks under seismic load

“…The study into the mechanical research methods of an underground pipe during an earthquake includes numerical analysis, theoretical calculation and experimental research currently. For numerical analysis, most scholars use the finite element method [14][15][16][17][18][19][20][21][22]. One common point of these studies is that scholars only focus on a single type of straight pipe, but not on elbows and tees of the pipe network.…”