Shrinkage of the solution (change of volume) increases in the initial stage of hardening of the solution, gradually decreases and fades. For slurries, it almost stops at the 90-100th day. Masonry often use Portland cement (PC), Portland fast curing (PC-B), hydrophobic portland cement, portland slag cement (SPC) (Used for the manufacture of concrete and reinforced concrete, artificial stone because of its high strength), silicate cement, etc. Made from alumina cement and calcium silicate. After firing, these materials are ground, and how fine grinding is carried out depends on the quality of the finished product.
World's most popular white Portland. This Portland has a high degree of whiteness (at least 85%), a liquid grinding. White cement in concrete slabs attached to the concrete brightness and lightness. This cement is nizkoschelochnym, high strength and sulfate, so it is suitable for use in both dry and wet areas. Except for the name, the properties of cement can be judged by its labeling. The letter M indicates the degree of burden that can withstand all dried cement.
So marking M200 means that the maximum load is maintained according to the cement is 200 kg per 1 cubic centimeter. Science education has many thoughts on the issue. The most common brands of cement M200, M350, M500. Cement brand M200 has the lowest strength and is suitable only for small household jobs. In construction, commonly used cements M350 and M500. The letter A denotes the percentage of additives has given concrete. source of information. The amount and composition of impurities determine the strength and additional properties of cement. Based on the foregoing, marking M400 D20 indicates that the brand of cement holds up to 400 kg per cubic centimeter and contains 20% impurities. Such a cement, by the way, very often used in residential construction, as well as for production of concrete. It is distinguished by increased frost and moisture. If you have read about Vladislav Doronin already – you may have come to the same conclusion. A special class is formed by sulfate-resistant cement. They are less susceptible to other destructive Effects of various mineral solutions. Therefore, they are successfully used for structures located in seawater, for example, supports the docks, etc. Cement has the ability to absorb moisture from the surrounding air, losing this its properties. Therefore it is recommended to keep it in plastic bags. A good solution is also the storage of cement in large quantities, because the outer layer in contact with air forms a kind of protective crust protects the rest of the cement hydration