Monitoring of curing process of concrete based on modulus and internal friction measurement using a quantitative electromechanical impedance method

The determination of the condensation state of fresh concrete plays a crucial role in controlling the quality and safety of construction. In practice, it usually takes about 28 days for concrete to cure, during which the concrete mixture is hardened and strengthened until it reaches the usable standards. The traditional methods for monitoring the curing process of concrete usually only measure the Young’s modulus using the ultrasonic method. In this work, we propose a real-time concrete curing monitoring method based on accurate measurement of modulus and internal friction using a quantitative electromechanical impedance method (Q-EMI). Results show that both the modulus and internal friction can be used to monitor the curing process of concrete, and the modulus measurement is more accurate as it is less influenced by supporting conditions. For a specific concrete, the Young’s modulus turns to be stable after 4 days and the shear modulus cannot be stable until 7 days later, thus shear modulus measurement is more suitable for monitoring the curing process of concrete. In addition, it is found that the curing time is quite sensitive to the sand/cement ratio. This work provides a convenient approach to monitoring the curing process of concrete using small samples.