Study on the hydration of young concrete based on dielectric property measurement

A nondestructive device is designed and employed to monitor the hydration of young concrete. The relative dielectric constant and amplitude can be measured by calculating the propagation time and intensity of electromagnetic impulses in young concrete, and the XRD and SEM are applied to investigate the mechanism of correlation between dielectric property and hydration process. Chemical admixtures (citric acid and triethanolamine) are used to verify the application of this method. The test results show that both the amplitude and relative dielectric constant (RDC) are ideal indicators of the hydration process. Microstructure observations demonstrate that the dielectric properties are strongly related to the formation of hydration products and changes of microstructure. The final setting time can also be achieved based on the amplitude measurement. This research provides theoretical and technical foundations for investigating the hydration of concrete, which enables us to have a better understanding of the hydration process.