Effects of mixing energy on technological properties and hydration kinetics of grouting mortars

During slurry preparation, effects of certain phenomena on fluidity and hardening characteristics of cement-based grouts have been reported. Deterioration of fluidity and hardening will affect the slurry performance, quality of workmanship and result in subsequent structural defects. There has been little research conducted on the effects of mixing energy during slurry preparation which has focused on the reasons or mechanisms for changes in characteristic properties. This work describes and measures the effects of several mixing parameters on properties of grouting materials, such as fluidity, hardening characteristics, shrinkage, heat of hydration, ion elution and crystallographic structure using X-ray diffraction and SEM. The results indicate that long mixing processes cause deterioration in fluidity and setting properties. These observations can be explained by acceleration in hydration kinetics and changes in microstructures and subsequent changes in dispersion states due to different mixing durations.