Predict the pipeline buckling using the broadening factor of Brillouin spectrum width

We monitored the distributed strain during the pipeline buckling process using distributed Brillouin sensor, which allows us to predict the buckling or crack location according to the sequence and location of the deformation for the first time using the broadening factor of Brillouin spectrum width. Two pipelines were designed and instrumented with polymer and carbon/polyimide coated fibers, and then the pipelines were subjected to internal pressure, axial tensile force and bending moment. We show that 1) the localized buckling occurred at the top, median and bottom of the pipeline, where the maximum broaden factors were obtained; 2) the deformation sequence can be measured using the nonlinearity of the broadening factor, 3) a high strength carbon/polyimide-coated fiber can detect higher stress accurately than standard telecom fibers. Our results strengthen the distributed Brillouin fiber sensor position as a nervous system to identify the potential problem in early stage for structural health monitoring.