Or use it right away. It's better to cover it right away, but cover it all. Cover it again when your face is closed. It won't work if it's late. Because cement curing needs proper moisture, it must react with moisture to increase the hardness of concrete.
After concrete pouring, it is a simple and effective curing method to adopt plastic film curing. Especially in the northern region, the temperature is high, the wind speed is high, and the air dries and loses water quickly. After curing with plastic film, the concrete moisture can be quickly blocked inside, and a long-term wet curing environment can be formed between the film and the concrete surface. After the final set, there is no temperature crack on the concrete surface, and the survival is neat and beautiful.
Attention should be paid to the timeliness of concrete film-covered curing construction, which must be completed before the initial setting of concrete. Membrane and concrete surface should be closely combined, without bubbles, and there should be no gap coverage and large area overlap between membrane and membrane, and the membrane surface should be watered later to keep wet.
Extended data
1, steam curing
Under normal pressure, the steam temperature is about 45 degrees (which belongs to the requirements of construction speed or external conditions), and the pressure 1 standard atmospheric pressure; Steam curing can improve the 28d strength10 ~ 40% of cement mixed with admixture; P ⅰ, P ⅱ and P 0 decreased 10 ~ 15%. The purpose of steam curing is to speed up the exertion of concrete strength and meet the requirements of speeding up the construction progress, and the construction is not affected by the external environmental temperature.
2, pressurized steam curing
Pressurized steam curing method: in order to obtain high-strength concrete, the uncondensed concrete is directly pressurized by machinery, or placed in a high-pressure container, and the temperature is quickly raised under pressure for steam curing.
3. Warm shed method
Use thermal insulation materials to build a greenhouse, surround the whole assembly or structure, and ensure the high temperature in the greenhouse. A steam pipe can be installed in the greenhouse, or a furnace can be directly used to raise the temperature in the greenhouse.
4, dry wet heat curing
Wet saturated steam has high heat content, which can quickly heat and condense concrete products with high exothermic strength during wet and hot curing, and at the same time ensure the necessary humidity conditions for concrete hardening.
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