A Comparative Study on the Impact of Different Antifreeze Agents on Composite Cement at −10 °C

Construction in cold regions faces significant challenges due to delayed cement hydration and frost damage caused by sub-zero temperatures. This study investigated the effects of three antifreeze agents on the performance of composite cement under sub-zero temperatures. The setting time, compressive strength, freezing point, and hydration mechanisms were evaluated. The results revealed that CaCl2 optimally accelerated hydration, while achieving the continuous development of compressive strengths through freezing-point depression and dense microstructure formation. NaNO2 exhibited the lowest freezing point but delayed setting at high dosages, while Li2CO3 showed limited impact due to insufficient freezing point depression. Li2CO3 showed limited efficacy under continuous low temperatures but enabled strength recovery after the temperature transition from sub-zero to ambient conditions. This research provides a basis for the application of antifreeze agents in the composite cement system for construction in cold environments.