New Understanding of Cement Hydration Mechanism through Electrical Resistivity Measurement and Microstructure Investigations

The new understanding for the hydration mechanism of cement has been achieved based on the noncontact electrical resistivity measurement. The cement hydration process is divided into dissolution, dynamic balance, setting, hardening, and hardening deceleration stages according to the characteristic points on the electrical resistivity development curve rho(t)-t and the differential curve d rho(t)/dt-t. The microstructure analysis corresponding to each hydration stage is conducted with scanning electron microscope, x-ray diffraction, differential thermal analysis, and Fourier transform infrared spectroscopy techniques. This study provides the theoretical foundation for understanding the relationship between setting behavior, hardening properties, and resistivity development.