Smart Monitoring of Movement and Internal Temperature Changes Within Polymer Modified Concrete Repair Patches
Polymer modified concrete repair materials (PMCRMs) offer significant protection to concrete reinforcement, if the PMCRM is compatible with the concrete substrate, and the instructions given by the manufacturer are followed. However, if the PMCRM is not compatible with the concrete substrate, or the manufacturer’s instructions are not followed, volume changes within concrete repair materials (CRMs) caused by shrinkage may result in the repair system failing by means of delamination or cracking. This paper demonstrates the use of an optical fibre strain and temperature sensor to provide valuable information regarding the movement and internal temperature changes which occur within concrete repairs, which may help extend the service life and provide a better understanding of PMCRMs. A strain measuring (fibre Bragg grating) FBG sensor was implemented to measure strain within a polymer modified concrete repair patch (PMCRP). The optical fibre monitoring system consisted of an internal temperature measuring FBG sensor and a strain measuring FBG sensor, which monitored the temperature and movement changes within a PMCRP. The device allowed for easy installation of the strain measuring FBG, and allowed for the optical fibre sensor to be reused, thus it was possible to measure both the internal temperature and the movement of the PMCRP soon after placement of the repair material.
This work was supported by Telkom, CBI, NLC and the URC of UJ.
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