Electrical resistivity measurement, piezoresistivity behavior and compressive strength of concrete: A comprehensive review

Strain sensors can identify the state of concrete buildings; however, they can only measure the local behavior of materials. To overcome this issue, researchers have created conductive materials capable of monitoring the behavior of whole concrete structures. Conductive steelmaking slag, including a significant quantity of iron oxide (Fe2O3), has been investigated for improving concrete monitoring. This study will provide an up-to-date sum-mary of the effect of steel slag as a partial replacement for aggregate and binder on the compressive strength (CS) and electrical resistivity (ER) of concrete. They have enhanced the concrete ER, sensitivity, and piezoresistivity, including steelmaking slag containing Fe2O3, the primary magnetite component (Fe3O4). According to earlier research findings, the partial substitution of coarse and fine particles with steel slag enhances the CS of tradi-tional concrete. In addition, this study will investigate the most influential factors influencing the ER of concrete, including water-to-cement ratio, types and sizes of aggregates, curing conditions, method of ER measurement two probes and four probes, probe spacing, specimen geometry, the effect of temperature and electrical frequency.