The Role of Sintered Clay Brick Powder During the Hydration Process of Cement Pastes

The effect of sintered clay brick powder (SCBP) on hydration properties of cement pastes was studied by using thermogravimetric and differential thermal analysis (TG–DTA), scanning electron microscopy and X-ray diffraction techniques in this paper, and the compressive strength was also tested. The test results indicate that the compressive strength of cement pastes decreases with the increase in SCBP content, but improves with the increase in the fineness of SCBP and curing temperature. Although SCBP in cement paste has little effect on the type of hydration products, it significantly affects the amount of the hydrates, especially for Ca(OH) 2 . The amount of Ca(OH) 2 in cement pastes reduces with the increase in SCBP content and curing age, while its microstructure is relatively dense, with abundance of calcium silicate hydrate gel (C–S–H) existing. SCBP in cement paste has high pozzolanic activity, especially for the finer SCBP and after higher temperature curing.