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How long does the cast-in-place concrete floor need to be cured?
The curing time of ordinary portland cement concrete shall not be less than 7 days and nights. When concrete may come into contact with flowing water after formwork removal, effective heat preservation and moisture preservation measures should be taken before concrete comes into contact with flowing surface water or groundwater. The curing time should be extended (at least 14 days) than the time specified in the above table, and the concrete strength should reach more than 75% of the design strength.

Before the concrete strength reaches 1.2Mpa, it is forbidden for anyone to walk on it, install formwork supports, and do not impact or chop on it.

During the curing period of concrete, the temperature of representative structures should be monitored, and the core temperature, surface temperature and environmental temperature, relative humidity, wind speed and other parameters of concrete should be measured regularly, and the curing system should be adjusted in time according to the changes of concrete temperature and environmental parameters, and the temperature difference between inside and outside concrete should be strictly controlled to meet the requirements. 、

The quality requirements of concrete curing water for extended data are as follows: it does not affect the workability and coagulation of concrete; Should not be detrimental to the development of concrete strength; Do not reduce the durability of concrete, accelerate the corrosion of steel bars, and lead to brittle fracture of prestressed steel bars; Don't pollute the concrete surface.

In the process of concrete hardening, the water demand for complete hydration of cement is about 25% of that of cement, and the rest water is used to meet the requirements of concrete construction and workability.

When the day and night average temperature is lower than 5℃ or the minimum temperature is lower than -3℃, it should be treated as winter construction. When the ambient temperature is lower than 5℃, it is forbidden to spray water on the concrete surface for curing. At this time, curing liquid can be sprayed on the concrete surface, and appropriate insulation measures can be taken.

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