Effects of temperature on performances and hydration process of sulphoaluminate cement-based dual liquid grouting material and its mechanisms

In order to find out the rules of the effect of temperature on performances and hydration process of sulphoaluminate cement-based dual liquid grouting material, the performances of the grouting material were studied by determining its setting time, compressive strength and setting temperature. Its hydration process, hydration products and microstructure were analyzed by using XRD, TG–DTA and SEM–DES. The results show that water temperature has a significant effect on the setting time and setting temperature. The higher the water temperature, the shorter the setting time and the higher the setting temperature. In addition, as the water temperature and curing temperature increase, the hydration rate grows faster and the early strength becomes higher. However, the later strength of samples which are with lower temperature is higher. The results of TG–DTA, XRD and SEM–DES show that ettringite (AFt) is the main hydration product. Higher water temperature and curing temperature accelerate the formation of AFt, but also restrict the later hydration rate. The type of hydration product does not change as the temperature changes, but the microstructure of hydration product does.