Hybrid Optical-Fiber/Alkali-Activated Material Sensor for Structural Health Monitoring Structures: Preliminary Results

In this work, a system for detecting temperature within structures useful for monitoring structural health during fire was realized. The aim is to monitor the temperature inside building materials when their external surface is subjected to a heat wave. This is extrinsic sensing material whose self-sensing capability is realized through the incorporation of an optical fiber as an intelligent sensing element. Specifically, Fiber Bragg Grating (FBG) technology was implemented within an innovative fire resilient alkali-activated material (AAM) and within a traditional cement-based material (OPC) for comparison. The performance of the two monitoring systems was compared in a test where heat waves in the proximity of a fire were simulated. During the heat test, traditional K-thermocouples (TC) were exploited to validate FBG sensors response. The preliminary results have demonstrated the applicability of this new AAM-based detection system to structures in high fire probability areas.