Nondestructive Wireless Monitoring of Early-Age Concrete Strength Gain Using an Innovative Electromechanical Impedance Sensing System

Abstract

Monitoring the concrete early-age strength gain at any arbitrary time from a few minutes to a few hours after mixing is crucial for operations such as removal of frameworks, prestress, or cracking control. This paper presents the development and evaluation of a potential active wireless USB sensing tool that consists of a miniaturized electromechanical impedance measuring chip and a reusable piezoelectric transducer appropriately installed in a Teflon-based enclosure to monitor the concrete strength development at early ages and initial hydration states. In this study, the changes of the measured electromechanical impedance signatures as obtained by using the proposed sensing system during the whole early-age concrete hydration process are experimentally investigated. It is found that the proposed electromechanical impedance (EMI) sensing system associated with a properly defined statistical index which evaluates the rate of concrete strength development is very sensitive to the strength gain of concrete structures from their earliest stages.

Experimental application of a wireless earthquake damage monitoring system (WiAMS) using PZT transducers in reinforced concrete beams

“…Further, on-line monitoring of concrete compressive strength gain using PZTs has successfully been achieved [13][14][15][16][17]. PZT admittances were also utilized in finite element method analyses that have been carried out for the evaluation of yielding or corrosion damage in steel reinforcing bars [1,18,19], to localize cracking in concrete beams [20,21] and to detect debonding damages in RC beams retrofitted with CFRP laminates [22,23].…”

Web-based concrete strengthening monitoring using an innovative electromechanical impedance telemetric system and extreme values statistics

“…Taking into account the results presented in the companion paper , for the purposes of the present paper, we introduce the term N out ‐R as the ratio between the amount of cumulative N out value changes and the elapsed time from the baseline measurement stage (3‐h from concrete casting). N out ‐R index is described mathematically by the following form: where t n is the n th sampling time from concrete casting and t 1 = 3 h. Table presents the values of N out ‐R index as computed by using equation for C3 specimen.…”

“…Cumulative value of concrete compressive strength changes according to Eurocode (EC2) formula. (a) From 3 h to 28 days (672 h) and (b) focus to time range between 3 h and 3 days (72 h) .…”

“…Taking into account the results presented in the companion paper [5], for the purposes of the present paper, we introduce the term N out -R as the ratio between the amount of cumulative N out value changes and the elapsed time from the baseline measurement stage (3-h from concrete casting). N out -R index is described mathematically by the following form:…”

Relative baseline features for impedance-based structural health monitoring

“…The applications of the impedance method have recently extended to assessing dental implant stability (Tabrizi et al, 2012), aircraft applications (Martins et al, 2012), wind turbine blades (Huh et al, 2014), corrosion monitoring (Talakokula et al, 2014;Yang et al, 2013), and concrete curing monitoring (Providakis et al, 2013;Yang et al, 2010). This technique is promising for assessing structural damage in real time, utilizing high-frequency excitations to examine changes in a structure's electrical impedance signature.…”