Miniature Resistance Measurement Device for Structural Health Monitoring of Reinforced Concrete Infrastructure

Abstract

A vast amount of civil infrastructure is constructed using reinforced concrete, which can be susceptible to corrosion, posing significant risks. Corrosion of reinforced concrete has various causes, with chloride ingress known to be a major contributor. Monitoring this chloride ingress would allow for preventative maintenance to be less intrusive at a lower cost. Currently, chloride sensing methods are bulky and expensive, leaving the majority of concrete infrastructures unmonitored. This paper presents the design and fabrication of a miniature, low-cost device that can be embedded into concrete at various locations and depths. The device measures localized concrete resistance, correlating to the chloride ingress in the concrete using equations listed in this paper, and calculated results from two experiments are presented. The device benefits from a four-probe architecture, injecting a fixed frequency AC waveform across its outer electrodes within the cement block. Voltage across the internal electrodes is measured with a microcontroller and converted to a resistance value, communicated serially to an external computer. A final test showcases the ability of the device for three-dimensional mass deployment.

Facial Fabrication and Characterization of Novel Ag/AgCl Chloride Ion Sensor Based on Gel-Type Electrolyte

“…Therefore, several research groups are investigating the development of nondestructive in situ monitoring techniques to measure Cl − ingress in RC structures, which can afford fast measurements with high reliability and realtime ingress profiles without destroying the structures (Abbas et al, 2013). Some existing nondestructive in situ monitoring methods include electrical resistivity measurement (Corva et al, 2020), fiber optic sensing (Bassil et al, 2020), potentiometry (Gandía-Romero et al, 2016), and chronopotentiometry (Abbas et al, 2013;Abbas, 2015). Among these, the chronopotentiometry technique based on an electrochemical method is employed for the indicative determination of Cl − content in infrastructures, the principle of which is described as follows.…”

Electrical Resistivity and Electrical Impedance Measurement in Mortar and Concrete Elements: A Systematic Review

“…Despite this is a recognized need, it is not widely addressed in the literature. Corva et al [156] proposed to use LCR meters to derive proper correction factors to be applied to the results to improve their accuracy. Priou et al [155] combined numerical models with laboratory tests to evaluate the uncertainty associated with the measurement and using water (instead of concrete) as a reference for calibrating the sensor to be used in-field.…”

Electrical Resistivity Sensors for Monitoring the Water Exchange in Hardened Concrete

“…Embedded sensors for the continuous monitoring of electrical resistivity have also been proposed in the literature [15][16][17][18][19]. The effect of influencing parameters such as the temperature has been evaluated [15,16].…”

“…Embedded sensors have been used for obtaining resistivity mappings on concrete samples [17]. Different miniaturized sensors have been proposed [18,19]. However, most of the proposed systems involve the use of a data-logger for the data acquisition and the presence of a technician for retrieving these data.…”