Mikhail Skvortsov In view of the majority, concrete - it is something gray and hard, used primarily for building foundations and slabs. In fact, a lot of concrete, they differ in structure and purpose, and appearance. On their variety we offer to talk in more detail. Gray and solid looks ordinary cement concrete, which is often used in country-house. It is based on cement, sand and water, combined in various proportions. And I think, once in a lifetime everyone had their own to make such a cement concrete - whether in the construction team during the construction of a garage or testimony, etc. In this case, not everyone knows that the cement can be heavy, lightweight, lightweight, honeycomb. Or, say, silica, polymer, or gypsum. To begin with cement concrete, which are prepared on the basis of various cements. Among these products is dominated by concrete on Portland cement, they make up about 65 percent of total production. In addition, the successful use of slag cement and concrete on putstsopanovom cement. The varieties include cement concrete decorative concrete (on white and colored cement), concrete for samonapryazhennyh designs (on bend cement), concrete for special purposes (for alumina cement). Silicate concretes prepared on the basis of lime, using autoclave curing method. Gypsum concrete make gypsum-based and used primarily for interior walls, ceilings and decor elements of buildings. These are the kind of concrete or sheetrock putstsopanovye concretes having high water resistance. They are used usually for the manufacture of bulk blocks of toilets and construction of low-rise buildings are in contact with water. Shlakoschelochnye concrete (they are still little used in construction) are preparing for crushed slag, using alkaline solutions. Polymer concrete is made on different types of polymer matrix, which is based on polyester, epoxy or urea resin, which then uses special additives cure. Such concretes are suitable for use in aggressive environments. Polymer concretes receive a mixed binder consisting of cement and polymer substance. Special concretes made with special binding agents, for acid-resistant and heat-resistant concretes used liquid glass or phosphate binder. Shlakoschelochnye concretes prepared with crushed slag, using alkaline solutions. Polymer concrete is made on different types of polymer matrix - such concretes are suitable for use in aggressive environments. Polymer concretes receive a mixed binder consisting of cement and polymer substance. Many of the properties of concrete depends on its density. The density of concrete is divided into very heavy with a density of more than 2500 kilograms per cubic meter, heavy (1800-2500 kg/m3), lung (500-1800 kg/m3) and high light (less than 500 kg/m3). Particularly heavy concrete make for heavy fillers - steel shavings or sawdust, iron ore and barite. In heavy concrete as a filler used rocks - granite, limestone, diabase. In the lightweight concrete used porous fillers: expanded clay, pumice, expanded slag, a particularly easy to carry cellular concrete - concrete, aerated concrete, which is produced by swelling of binder on special technology. Concrete Construction Heavy concrete is on the foundations and vaults in the monolithic housing construction, lightweight and very easy to apply for internal walls and partitions. In the building regulations clearly indicate the use of concrete of any kind. Designers use them when deciding design problem, hoping to load for the building. Concrete is used for various kinds of designs, as-manufactured and erected directly on the site. First, we should mention the foundation blocks, made of reinforced concrete grade 200. They can weigh three tons, while the lower base blocks is done with an extension downwards, and the basement wall blocks (also up to three tons) have a rectangular cross section and can be either solid or with voids. Concrete is divided into very heavy with a density of more than 2500 kilograms per cubic meter, heavy (1800-2500 kg/m3), lung (500-1800 kg/m3) and high light (less than 500 kg/m3). Heavy concrete is on the foundations and vaults in the monolithic housing construction, lightweight and very easy to apply for internal walls and partitions. Wall concrete blocks can weigh from a few tens of kilograms to three to five tons. They are made of conventional or macroporous concrete. Sometimes these units are complemented by a special valve, which facilitates their capture during the installation of the wall. In some cases, the inner wall of the block pre-coated with plaster. Concrete also made joists - rectangular section and flange tees. Their length can reach six meters or more. Beams of up to six meters are made of ordinary concrete, more than six - reinforced concrete. In addition, concrete can be made staircases, and various architectural details for the decoration of the facade: small caps, casings, cornices. Reinforced concrete has been applied in the manufacture of fencing for the suburban areas - these fences in no way inferior to iron, but cheaper. Cellular Innovations Strictly speaking, the cellular concrete is no longer a novelty: these building materials have long created their supporters, and their application in a country-house with every year. But in comparison with traditional concrete, aerated concrete blocks and still are more novel and advanced materials. Aerated concrete - lightweight material with excellent insulation characteristics, strong and durable. It can decorate almost any material, including brick and wood, very easy and cheap to transport. The use of porous concrete blocks can significantly reduce labor costs and speed up construction of homes. Basis of foam - a mixture of binder and silica components with the addition of frother. After mixing with water, it swells, buying a cellular structure. The result is a lightweight material with excellent insulation characteristics. Ability to retain heat well - the main advantage of cellular concrete. For example, a 20 cm foam on teplosberezheniya corresponds to 40 cm or 140 cm wooden bricks. Under the new SNiPs thermal resistance of materials for our region should not be less than 3.060 C m2/Vt. So, this requirement is fulfilled when the thickness of walls of sand-lime brick 2,5 m, and from the foam - just 37 cm! Therefore, the cost difference is obtained significant: for the house of the same area and price-rise foam as a wall material is approximately three times less than the cost of wooden beams, and five times less than the cost of bricks. In addition, the use of foam concrete blocks can significantly reduce labor costs. Labour productivity in their clutch - higher than when using standard bricks, so a square meter wall costs about two to three times cheaper. Finally, the reduction in weight of the wall (a wall of foam concrete is much easier to brick!) Leads to savings on frames, structures, piers and piles. Foam concrete is made both in stationary conditions, as well as directly on site, where with the help of mobile equipment can be part of a given density. In the first case it is applied in the form of blocks, the most standard sizes - 500 ? 400 ? 200 mm. In the second - in liquid form. High-density foam concrete is used in the construction of the foundation or floor slabs. Less dense material used for the manufacture of precast blocks and panels partitions in buildings for insulation of floors and roofs, as well as to fill the voids and insulation. Which is better - the use of ready-made blocks or to use the technology fills directly at the site? It depends on your goals and opportunities. Finished foam concrete blocks of size greater than brick, and one can very quickly build a wall. As the use of reinforced concrete slab floor that is also beneficial in terms of saving time. In this case, you will immediately receive a geometrically precise "box" that can immediately finish. But in the case of liquid foam will not need much time. Initially made of wood frame or light steel structures. Next is the outer veneer with any material (brick, DSP, etc.) and the lining. And then between the outer and inner layers is filled with foam concrete. By weight of a foam concrete is even lighter than the finished blocks, and fill do not last long. So, once again list the positive qualities of foam. This is a very reliable material, it is virtually unaffected by time, that is constructed from his house can stand for many decades. Closed pores hinder the absorption of moisture foam, and its increased compression strength allows to obtain material with good bearing capacity. On the thermal protection mentioned above - it is ensured that the aerated concrete is largely composed of air bubbles, and air, as we know, the best heat insulator. Home of the foam can accumulate heat and eventually significantly (20-30%) to reduce heating costs. Foam concrete and protects from heat, and also regulates the humidity in the room, creating a comfortable climate in a country house. In the aerated concrete is very easy to cut channels for wiring, sockets, pipes and ducts. Foam concrete is an excellent sound insulator in aerated concrete building you will be well protected from the noise of passing nearby tracks or sound running in the lean diesel generator. This material does not emit toxic substances in their environmental quality second only to timber. But it is fire-resistant, that is not destroyed by heat, and, naturally, does not ignite. Foam concrete is easy to process, it is unrestrained imagination of the customer and the architect. It can decorate almost any material, including brick and wood. Foam concrete is easy and cheap transport - for transportation of finished blocks can use any kind of transport. Another member of the family of aerated concrete - aerated concrete. He also belongs to a relatively new building materials, but, again, enjoys considerable demand in the construction market. In fact is aerated artificial stone, which is produced by special technology. The water is mixed cement, ground sand, thoroughly pulverized lime and gypsum is added to aluminum powder. After that, in a warm moist chamber mixture swell, rises and turns into an array of aerated concrete. Array is cut into blocks and put them in the autoclave oven, where they are quenched by water vapor at a pressure of 12.8 atmospheres and a temperature of 200oC. Manufacturers of quality gas concrete lot, in particular, has a good reputation of Estonian products manufacturers. In St. Petersburg, quality aerated on German equipment produces 211 KZHBI. German technology delivers high geometric accuracy blocks, uniform density and an array of the best indicators of the strength of available blocks and reinforced panels. Aerated concrete (as well as aerated concrete) has excellent thermal insulation properties: Laid-wall out of it effectively protects the country house from the cold, while being relatively thin. Compared with what? Of course, with traditional brick. In order to meet the exterior walls of heat-insulating properties of the requirements of SNIP, just select the aerated concrete thickness of 400 mm at a density of 500 kg/m3. The walls are also made of brick with the same parameters on the thermal conductivity should be not less than 640 mm. The weight of one square meter of aerated concrete wall will be three times lighter than a brick wall of the same area. And hence, the cost of the foundation under the house with walls made of aerated concrete will be significantly less. If here include shipping costs (delivery of aerated concrete is also very simple operation), the result is a very serious savings. And because the popularity of aerated among builders is not surprising. Another plus of aerated concrete - the possibility of rapid erection of walls, as the building blocks of aerated concrete more than even large-format bricks. Aerated concrete can be for one season it is easy to build a reliable and warm country home. Durability of the finished wall - at least 100 years. In addition to blocks is also reinforced in the form of aerated concrete beams, slabs, etc. So, a family of concrete - a rather large, but is unlikely to remain unchanged. Technologies are evolving, and in this area of ??the construction industry will certainly be surprises and surprises.
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