At low temperatures, the hydration rate slows down, which affects construction efficiency. When the temperature drops below freezing, water turns to ice, expands in volume, and is prone to causing defects like hollowing and peeling. After the water evaporates, internal voids increase, significantly reducing the mortar’s strength.
The strength of mortar mainly depends on the reaction rate and duration of cement and water. When constructing below 0°C, water freezes, and although hydration is an exothermic reaction (which provides some hydration temperature), the efficiency of cement reaction still decreases. Once the temperature rises above 0°C, the ice melts, and hydration resumes—but this cycle inevitably reduces the cement’s strength.
Post time: Dec-17-2025