Utilising hydraulic transient excitation for fatigue crack monitoring of a cast iron pipeline using optical distributed sensing

Abstract

Summary Corrosion‐induced failures are common in cast iron pipes used in water supply networks. Over times, cracks may initiate from the corroded pits and grow when subjected to fatigue internal loading. When the particular region of the pipe loses its structural capacity, it will eventually lead to leakage or even pipe burst. Thus, it is important to perform permanent and real‐time integrity monitoring on these pipelines. Distributed optical fibre sensors (DOFS) have been proposed to monitor the structural health of water pipelines for the last few decades. Most of the previous studies have shown that DOFS is effective in monitoring the condition of a pipeline subjected to static operating pressure. This paper aims to experimentally demonstrate the ability of distributed optical fibre strain sensor to monitor the fatigue crack growth along the cast iron pipeline subjected to pressure transient. The fatigue test was conducted using a large‐scale cyclic internal pressure loading facility. The DOFS was instrumented on the pipe to monitor the condition of the pipe when subjected to internal pressure loading approximation of water pressure loading (operating pressure and pressure transient) experienced in the field. The measured response will show the potential application of DOFS for crack detection, as well as monitoring the fatigue crack growth along the pipe. The results confirmed that DOFS is able to enhance the detection of cracks along the pipe subjected to pressure transient.

Research on Adaptive TSSA-HKRVM Model for Regression Prediction of Crane Load Spectrum

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Condition monitoring and temporal‐spatial assessment of composite pipeline transporting potable water

“…Therefore, fiber optic sensing, with its superior properties including exemption of electricity supply and cumbersome wiring, immunity to electromagnetic interference, lightweight, long‐distance transmission, anti‐corrosion, and strong applicability in inferior environments, 18–20 is considered as an ideal candidate. Optical fiber sensors, mainly inclusive of the fiber Bragg grating (FBG) and distributed optical fiber sensors, have proved their potential applicability in pipeline monitoring 21–26 . Over the past years, FBG sensors emerge as a cost‐effective and reliable choice in this area.…”

“…Optical fiber sensors, mainly inclusive of the fiber Bragg grating (FBG) and distributed optical fiber sensors, have proved their potential applicability in pipeline monitoring. [21][22][23][24][25][26] Over the past years, FBG sensors emerge as a cost-effective and reliable choice in this area. They already find wide applications in the monitoring of pipelines for transporting riskier hydrocarbon liquids (e.g., fossil fuels, gases, and chemicals) and in harsh environmental conditions (e.g., subsea pipelines).…”

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“…According to the mathematical model of the pipeline and the changes of the measured parameters, the pipeline leakage can be detected. There are mainly negative pressure wave method, 19 pressure gradient method, 20 water balance method, 21 and transient analysis method 22,23 . These methods can be used for real‐time monitoring.…”