Ballast breakage analysis using FBG acoustic emission measurement system
Fibre Bragg grating (FBG) based acoustic emission (AE) measurement technique is utilized to monitor ballast breakage activities during uniaxial compressive loading. AE activity is recorded continuously using an FBG attached to the ballast sample and using a high speed FBG acoustic interrogation system. Crack induced AE events, amplitude, spectrograph of AE frequencies and strain induced by the cracks are obtained using the fibre optic system. This information can be crucial in analyzing ballast breakage, one of the key parameters that determine the permanent settlement of railway track. The successful implementation of the method underpins the potential of using fibre optic acoustic emission method to study ballast breakage with further investigation into the frequency analysis and modelling the spectrum of AE at microscopic level can shed light into a deeper understanding of railway track settlements.