Vectorial dislocation monitoring of pipelines by use of Brillouin-based fiber-optics sensors

Abstract

In this paper, we propose and experimentally validate the use of a distributed optical fiber sensor for monitoring pipeline dislocation. The proposed technique is based on the measurement of the normal strain, by use of stimulated Brillouin scattering, along three longitudinal directions running along the pipeline. We demonstrate that, by choosing three lines reciprocally displaced by 120 • around the circumference of the pipeline, it is possible to measure the amount and direction of pipeline dislocation. The longitudinal position at which the deformation occurs is also evaluated. The measurements achieved by using the proposed technique can be directly used to monitor the structural integrity of the pipeline, as well as to monitor the deformations of the rock/soil surrounding the pipeline. This can be of importance to monitor geological events. Numerical simulations carried out by the finite-element method have been employed to evaluate the accuracy of the measurements.

Distributed fiber optic sensors for monitoring pressure and stiffness changes in out-of-round pipes

“…Specifically for pipes, it has been shown that Brillouin Optical Time Domain Analysis (BOTDA)‐based distributed fiber optic sensors instrumented on and around a buried pipe can be accurately used to detect changes in its strain profile caused by pipe bending induced by ground movement . Vectorial dislocations of a pipe displaced in any direction can also be detected using BOTDA sensors installed 120° apart along the axial length of the pipe . Changes in internal pressure along with changes in the wall thickness of a pipe, whether due to corrosion or manual removal of material, were also able to be monitored with the use of BOTDA sensors .…”

Long-Term Monitoring of a Tunnel in a Landslide Prone Area by Brillouin-Based Distributed Optical Fiber Sensors

“…The optical fiber technology has also been applied for the realization of fiber-optic inclinometers, where the fiber is glued along parallel directions of the tube. It has also been shown that, by processing the acquired deformations, a three-dimensional reconstruction of the displacement distribution can be obtained [19,20]. Compared to conventional inclinometers, fiber-optic inclinometers provide a continuous deformation profile and measure a larger deformation of the tube before getting out of use.…”

Numerical Simulation of The Response of An Underground Pipeline Connector With a Super-Large Section Under Complex Geological Conditions

“…Stajanca et al 11 studied the impact of pipeline vibration response on gas leakage. Different methods exist for conducting experimental research on the mechanical conditions of gas pipelines: vibration sensors 12,13 ; strain gauge applications 14 ; checking the capabilities of optical fiber sensors 15,16 ; and acoustic and ultrasonic detection methods 17,18 .…”