But in summer, the strength of ordinary concrete is enough for curing 15 days. For example, in winter, sometimes the condition of concrete pavement is very poor, and it is difficult to achieve sufficient strength even after two months of maintenance. However, no matter what the curing conditions of concrete are, the first 7 days should be kept warm and moist. For structures with harsh maintenance conditions, warm water or even pressure water can be used for maintenance.
Extended data:
Cement and water become plastic semi-fluids. After a period of time, the cement slurry gradually loses its plasticity and maintains its original shape. This phenomenon is called coagulation (divided into initial coagulation and final coagulation). Then enter the hardening period, and the cement strength gradually increases.
The setting time of cement is required to have a certain range in construction. If the setting is too fast, the concrete will soon lose its fluidity, which will affect the vibrating; On the other hand, if the condensation is too slow, it will affect the construction speed. Therefore, the standard stipulates that the initial setting time and final setting time of cement should be within a certain range.
The setting time is determined by using cement slurry with standard consistency under certain temperature and humidity conditions. Judging from the time of adding water, the distance between the test needle and the bottom plate is 0.5 ~ 1.
Omm, the required time is the initial setting time, when the paste begins to lose plasticity; Until the test needle sinks into clean mud, it shall not exceed 1.
Omm, the required time is the final setting time, when the slurry completely loses plasticity and begins to enter the hardening period.
References:
Baidu encyclopedia-cement