Smart textile embedded with distributed fiber optic sensors for railway bridge long term monitoring

Abstract

The Structural Health Monitoring (SHM) of large civil infrastructures has become a priority due to economic advantages and early detection of structural failure. Distributed Fiber Optics (DFO) sensors are becoming widely used for SHM due to their immunity to Electromagnetic interference and the ability to collect multiple data points from a single fiber cable. However, its reliability for a long monitoring period is still an area of interest. This paper studied the long-term performance of DFO embedded into textiles for faster installation procedures. The aim was to understand if the textile distributed fiber sensor experience any signal degradation after multiple weather seasons. To perform this investigation a railway bridge was used as a case study. The data was collected using Brillouin Optical Time Domain Reflectometry (BOTDR) and Brillouin Optical Time Domain Amplification (BOTDA). Additionally, a temperature compensation technique was investigated to remove the cross-relation between temperature and strain. The final results show the sensor’s effectiveness for long-term monitoring, where the data quality remained constant with an average standard deviation of 0.455 for the BOTDR and 0.208 for the BOTDA approaches.