The effective frost resistance time is before the concrete reaches the critical frost resistance strength. After reaching the critical strength, concrete is not afraid of freezing, and antifreeze has no effect. But the premise is that antifreeze is a qualified product. As for the specific time, it is related to factors such as air temperature, molding temperature, covering and maintenance methods, and cannot be generalized.

Antifreeze generally has the function of anti-freezing and early strength, which can reduce the freezing point of concrete in winter and not freeze at low temperature, which has the function of early strength, that is, accelerating the setting speed of concrete. If you say that adding antifreeze delays the setting time, it should be the slow setting of concrete caused by low temperature. If antifreeze is not added, it is easy to freeze.

Anti-freezing and anti-coagulation work in winter in chemical plants is the main means to ensure safe production. In order to prevent all freezing accidents, according to the characteristics of the device, the anti-freezing and anti-coagulation work should also be carried out in accordance with the principle of "prevention first, elimination second". Strengthen the collection, distribution, use and management of easy-to-freeze and easy-to-coagulate articles, prevent them in advance according to basic methods, carefully check them according to regulations, reasonably deal with the problem of freezing and blocking, and ensure safe production.