Cement

Cement - one of the most well-known binding of construction materials and treats, a group of hydraulic binders, which ispolzuyutsyadlya bonding various surfaces (bricks, concrete blocks, etc.). The structure consists of silicate cement and calcium aluminates, which are the result of firing up to the sintering raw mix. Natural cement - a mixture of clay and limestone, which in solidification forms a high strength material. Cement - this is often the bulk material gray odorless. The quality of cement is determined by the content in it of various substances, such as granulated slag, anhydrite sulfuric acid, magnesium oxide. So, in what proportions these substances are found - this will cement brand. Because of the content in the cement of these substances depends on the quality of cement, compressive strength, setting time, the presence or absence of false cement setting also need to know what brand of cement to the limit of the bending strength of samples, cross members 40-40-160 mm in size and compression of the halves of the plastic solution of 1:3 (by weight) at 28 days, and fast curing of Portland cement and slag Portland cement - after 3 and 28 days, for alumina cement - after 3 days. There are such types of cement: - Portland cement - Slag Cement - plasticized cement - pozzolan cement - calcium aluminate cement - Cement Acid Acid cement - produced by co-grinding or mixing of separately milled quartz sand and sodium fluorosilicate . Such a cement mix with an aqueous solution of sodium water glass. The advantage of acid-proof solution is its resistance to mineral and organic acids. A disadvantage is that it is fragile in the water, and caustic alkalis. Acid cement is used for acid-resistant concrete (solutions). plasticized cement - this type of cement prepared by adding to the cement mixture is 0.25% sulfite-alcohol vinasse-count needed by weight of dry cement. spetsialnayadobavka This is a surfactant. The advantage of this stanovitsyaplastifikatsiya cement concrete, and, importantly, reduce consumption of cement is reduced the ratio of water: cement Partner code adverse effect on the mobility of mixtures increases frost characteristics. Portland cement (calcium silicate cement) - is a hydraulic binder which hardens and water and air. is a greenish-gray powder, and for the preparation of cement mortar to add water, and then takes kameneobraznoe Portland Portland state produced by co-pulverizing the clinker and gypsum as the main tehnologicheskimistadiyami upon receipt of Portland cement are: production of raw mix, making it by firing up the sintering of the clinker and grinding, the latter to a fine powder. Slag Cement - type cement, which is obtained by the simultaneous grinding of granulated blast-furnace slag and additives-energizers (lime, plaster, anhydrite, etc.). Slag cement is used for mortar and concrete, pozzolan cement - a group of cement in the composition which contains at least 20% active mineral additives. The difference pozzolan cement is a high resistance to corrosion, especially in soft and sulfate waters, low frost and slow curing. So do not use this cement in structures that are subjected to rapid drying, or have alternate drying and wetting, as well as in the frost-resistant concrete. aluminous cement - it's fast hydraulic cement binder, which is obtained by pulverizing roasted to sintering or fusing the rich alumina raw material mixture. ispolzuetsyaizvestnyak For raw materials, lime, or rock, with a high content of alumina. aluminous cement - a fine powder gray-green, brown or black. fasten aluminous cements begin after 45 minutes, none later than 10 hours. The advantages of alumina cement is hardening in a moist environment, while adding cement in concrete, it ceases to be watertight, frost-resistant, korrozostoykim. This cement can be constructed in the winter at low temperatures. aluminous cement - one of the most fire-resistant cement to 1700C °. aluminous cement is used in conditions with high temperatures, corrosive water or gas media (acids, alkalis, salts). How to decipher markings cement? marking cement is indicated by two features: the ability to withstand a certain load and percentage to the total volume of cement of various additives. Ability to withstand a load of cement indicated by the letters M or PC and ryadomstoyaschey figure. The higher the number, the stronger the concrete. The most popular cements with marks from 350 to 500, and tsifraoboznachaet that the cement can withstand a load of 500 kg / cm . Percentage - is parametrtsementa, which displays the percentage of additives, denoted by the letter D. For example, cement labeled D30 will contain 30% additives. Danai characteristic of cement is important because it affects the ductility and strength of cement. As mentioned above, The most popular brands of cement are brands of 350 to 500. The basic characteristics and application of some of them.