The effect of high-calcium coal combustion product and admixtures on the early hydration properties of aluminate cement

This study used coal combustion products (CCP) with different calcium contents to replace partial aluminate cement (AC) in equal amounts, and studied the effect of calcium contents on the setting time and early compressive strength of AC. The setting time and early compressive strength were further regulated by adding retarder. The results showed that the higher the calcium content of CCP (CCP2 contains higher calcium content), the shorter the setting time and the higher the 2 h compressive strength after replacing part of cement. By adjusting the ratio of AC and CCP2 within a certain range, there is a synergistic effect between AC and CCP2. When the ratio is 2:3, the maximum 2 h compressive strength is 3.5 MPa. After adding retarder A to AC-CCP2 binary system, the setting time can be regulated and early compressive strength can be significantly improved, indicating that there is a synergistic effect between retarder A, AC and CCP2.