Underground main pipeline behaviour under a travelling impulse in the form of a triangle

Barna Rakhmankulova,Saparboy Khusainov,Rakhmatjon Khusainov,Sayibdjan Mirzaev,D Bazarov

doi:10.1051/e3sconf/202126401006

Abstract

The article presents an analysis of the dynamic response of an underground main pipeline under the action of a longitudinal wave, propagating in soil along the pipe. It is assumed that the elastic pipe has a finite length. A linear viscoelastic model of the "pipe-soil" system interaction is considered. The influence of a pulse in the form of a triangle on the deformed state of an underground main pipeline is investigated. The article presents a comparative analysis of the results obtained for some values of the coefficients of elastic and viscous interaction, the propagation velocity, and the duration of the pulse. In the case of elastic interaction of the "pipe-soil" system, the reflection of the wave propagating in the underground pipeline on the boundaries of the pipeline when it coincides with the wave propagating in the soil leads to an increase in the maximum deformation of the underground pipeline, the value of deformation can double. The viscosity coefficient of interaction at the pipe-soil system contact leads to the wave front attenuation in the underground pipeline. For soils with the coefficient of viscous interaction higher than 100 kN∙s/m2, this leads to complete attenuation of the bursts at the wave front in the pipeline. The influence of the wave propagation in soil on the deformation values at the wave front was also studied.

Highlights

Underground pipelines are a key component of critical life support systems such as water supply, gas and liquid fuels, sewerage, electricity, telecommunications
The interaction with the soil structure caused by seismic waves has an important effect on the pipeline behaviour, and the integration across the entire pipeline network affects the performance of the entire system [1, 2]
The wave propagation velocity in a steel pipeline is assumed 5120 m/s, and in the ground, this velocity depends on the soil type

Summary

Introduction

Underground pipelines are a key component of critical life support systems such as water supply, gas and liquid fuels, sewerage, electricity, telecommunications. The exceptional damage caused by the 1985 Michoacán (Mexico) earthquake prompted researchers to develop sophisticated tools for assessing ground motion in the Michoacán Valley (Mexico City) during earthquakes along the Pacific coast, including important effects observed in the city. These tools have helped to better understand how earthquakes affect buildings and other structures (including pipeline systems). Serious damage to underground pipelines caused by the effect of surface wave propagation was observed during the 1985 Michoacán earthquake in Mexico City [3]. Analysis of the soil structure interaction with surface waves propagating along underground pipelines is of practical importance for assessing pipe damage and the response of a life support system. Observations of previous earthquakes show that the axial thrust in joints is the main type of destruction of segmented pipelines [2,3]

Methods

Results

Conclusion