Correlation relationships of elementary mechanical properties and electrical resistivity of structural concrete

Concrete is a typical material used in structures exposed to the combined effect of aggressive substances and mechanical stress. This combination leads to problems with durability, loss of load capacity and safety. The research was carried out in order to evaluate three performance parameters, namely compressive strength, dynamic modulus of elasticity and durability due to corrosion caused by chlorides. Two different non-destructive testing devices (NDTs), namely a 4-point Wenner Probe and an rCON meter, were used to examine surface resistivity (SR) and volume resistivity (BR) in a very short test time. These are important properties of hardened concrete related to the corrosion resistance of reinforced concrete structures. An ultrasonic method was used to determine the dynamic modulus of elasticity. The article shows the correlations between the measurement of surface and volume electrical resistivity against the elementary characteristics of plain concrete C40 / 50. These correlations are analyzed at different times since concreting, thus providing a description of maturing of concrete.