Because the hydration of cement requires a certain temperature, the hydration speed is fast and the strength of concrete increases rapidly. The national standard stipulates that 20 2 is the standard temperature of concrete. With the decrease of temperature, the hydration speed of cement gradually slows down, and when the temperature is lower than 5, it is close to stopping hydration. If the concrete has no strength due to solidification and hardening, it is impossible to remove the formwork and enter the next working procedure. Therefore, it is stipulated that winter construction measures should be taken when the average day and night temperature on the construction site is lower than +5℃ for three consecutive days or the minimum temperature is lower than -3℃ for three consecutive days.

Common winter construction measures: steam curing method, greenhouse method, heat storage method, etc.