This paper investigated the effect of nano-calcium silicate hydrate (n-C-S-H) on the early compressive strength of mineral powder-cement systems under low-temperature curing conditions (5 °C). The hydration mechanism of n-C-S-H in the mineral powder-cement system at different dosages was analyzed by combining it with XRD, DSC-TG, MIP, and other techniques. The results show that n-C-S-H significantly enhances the early compressive strength of the mineral powder-cement system under low-temperature curing conditions, with optimal results observed at a dosage of 1.0% (mass fraction). The XRD, DSC-TG, and MIP tests reveal that n-C-S-H promotes the hydration of the mineral powder cement, accelerates the generation rate of hydration products, reduces the porosity of the hardened mineral powder-cement slurry, and improves the system's density.
Keywords: early compression strength; hydration mechanism; mineral powder-cement system; nano-C-S-H; porosity.