Journal Article

Dynamics of Steel Gas Pipelines: Finite Element Simulation of Damaged Sections Reinforced with Composite Linings

Moldagaliyev, Arman, Zhangabay, Nurlan, Bonopera, Marco, Ristavletov, Raimberdi, Ibraimova, Ulzhan, Yeshimbetov, Shairbek

2025

Overview

Based on a reduced model of a linear section of a steel gas pipeline between four supports and with a crack-like through defect, ANSYS FE software is used in this study to develop numerical approaches regarding three key parameters of a composite bandage in the form of a circular lining: the type of composite material and the length and thickness of the composite lining. The approach for assessing the static strength of a damaged section of a steel pipeline with a composite lining that is subjected to internal pressure allows for the determination of the optimal thickness of the composite lining itself, which is equal to the indicator “50.0% to 62.5%” of the pipe thickness. Furthermore, the approach for assessing the dynamic strength and analyzing the possible destruction of the reinforced damaged section of a pipeline experiencing an increase in internal pressure allows for the determination of the optimal length of the composite lining, which, in turn, should be at least 241.2 mm. This work also considers cases when there is no internal pressure and the steel pipeline is subjected to critical pressure. It is found that the frequency spectrum of pipeline oscillations without a composite lining is higher than that with a composite lining. The difference between the corresponding dynamic oscillations increases with the thickness or the length of the composite lining. In the absence of internal pressure, all frequencies of the steel pipeline with a crack closed by a composite lining are paired. This pairing is disrupted when the pipeline is subjected to critical internal pressure, and the difference between its oscillation frequency spectrum without and with a composite lining increases. In this case, the oscillation modes significantly differ from those of the same pipeline structure when unloaded. The results ensure the optimal stress distribution in the defect area of a steel pipeline wall and improve the reliability and safety of pipelines under seismic actions. The approach for increasing dynamic strength and eliminating defects can be applied to pipelines with a large diameter regardless of the causes and geometric dimensions of the defects. Moreover, this approach to increasing the strength can be used by various industries and/or institutes which work on the design of new, earthquake-resistant, reinforced pipelines.

• Publisher: MDPI AG
• Subject: Analysis / Carbon fibers / composite lining / Composite materials / Cracks / Critical pressure / Defects / Dynamics / Earthquake damage / Earthquake resistance / finite element / Finite element method / Frequency spectrum / Gas pipelines / Internal pressure / Linings / Mechanical properties / numerical simulation / oscillation frequency / oscillation mode shape / Oscillation modes / Pipelines / pressure / Seismic engineering / Steel pipe / Steel pipes / Stress concentration / Stress distribution / Thickness