Can 425 cement water the floor?
1. When the design label of floor concrete is C30, 32.5-grade cement cannot be used, because too much cement is used in the mixture ratio, which often leads to large hardening shrinkage and cracks.
2. When the design grade of floor concrete is C25, it is ok, but it is not very suitable;
3. When the design label of ground concrete is C20, you can safely use grade 32.5 cement according to the mixture ratio.
4. Cast-in-place floor slab can use 425 cement. According to the residential online network, No.425 cement has high grade, fast hardening time and long service life for the floor.
How to quickly understand cement quality
1, because cement is afraid of moisture, good cement will be packed in moisture-proof laminated woven bags, and the trademarks and words on it are very clear, including brand, place of origin, trademark, grade, model, production date and so on, all of which are indispensable.
2. Most owners have no experience in this field when buying cement, so they must listen carefully to the explanation of the merchants, especially the composition of cement, which is the key to determine the quality of cement. If consumers don't know the standard ratio, they can directly check it online.
There is a lot of cement in the market. If consumers want to buy high-quality products from it, they must learn how to face the merchants. First of all, the brand dealer should have a power of attorney, followed by the production process of the product. Although I don't understand, I can also get information from the expressions of the merchants.
4. According to the residential online network, under normal circumstances, the shelf life of cement is about three months, but in fact, cement is a fragile product. The strength of cement with a production date of more than one month will decrease. The longer it takes, the more it decreases. So when purchasing, the earlier the production date, the better.
Can you stir the cement?
1, it is generally not allowed to mix different brands of cement during construction, nor should it be mixed. For example, the mixing of 325 and 425 cement and the mixing of 42.5 and 32.5 cement of the same variety can only be used according to the cement index of 32.5, and the strength grade, setting time and other properties of mortar need to be determined by experiments, which cannot guarantee the design requirements. If different kinds of 325 and 425 cements are mixed, mortar is prone to flash setting or rapid setting, and concrete is also prone to cracking due to different setting time.
2. In addition, when mixing cement, water and sand should be added in proportion, and the added water cannot contain organic matter, so as not to affect the setting time of concrete, thus affecting the strength of concrete. When pouring cement mixture, it is not allowed to leak slurry, it should be vibrated reasonably, and the later maintenance work should be done well.