Feasibility of Using Resin-Jacketed Piezo Sensors for Monitoring of Concrete Strength using Electro-Mechanical Impedance Technique

The present study is on the feasibility of the effectiveness of the embedded resin-jacketed piezo (RJP) sensor for monitoring concrete strength using electromechanical impedance (EMI) technique. In this study, first resonant peak frequency in the EMI signature is preferred over other quantitative indices, including ischolar_main-mean-square-deviation (RMSD) and equivalent stiffness parameter as they are based on frequency ranges chosen by a particular user’s judgement. The piezo sensors used are lead zirconate titanate (PZT) based thick (1 mm), circular patches of diameter 10 mm coated with epoxy resin. The protective resin coating imparts robustness to the sensor against the rough conditions during concrete casting. The ease in fabrication and utilization of the proposed embedded configuration of the RJP sensor renders it as an appropriate choice for use in real-life site conditions. Based upon the peak resonant frequency, RMSD and equivalent stiffness parameter determined using EMI signature, we conclude that it can successfully monitor concrete strength up to first 28 days.