Monitoring of reinforced concrete structures by distributed optical fiber sensors

Abstract

Distributed Optical Fiber Sensors (DOFS) are modern-day cutting-edge monitoring tools that are quickly acquiring relevance in the Structural Health Monitoring engineering. Their most ambitious use is embedded inside plain or reinforced concrete (RC) structures with the scope of comprehending their inner-workings and long-term performance. Yet, multiple studies have shown that the bonding technique with which the DOFS are bonded to the reinforcement bars has a significant role on the quality of the extracted strain data. Whilst this influence has been studied for externally bonded DOFS, it hasn’t been done for embedded ones. The present work is set on performing such study by monitoring the strain measurement quality as sampled by DOFS bonded to multiple rebars with different techniques and adhesives. These instrumented rebars are used to produce differently sized RC ties later tested in tension. The discussion of the test outputs highlights the quasi-optimal performance of a DOFS/rebar bonding technique.