What is the secret of the strength of reinforced concrete products?
Reinforced concrete is an "assortment" of two strong materials: concrete and steel. The reinforcing mesh pervades inside the entire concrete "pie", shifting to itself the function of damping the "uncomfortable" loads in the system. If the frozen cement-sand mortar itself can withstand weight well but is not able to withstand the pressing forces( bending), then, in conjunction with the metal partner, the finished reinforced concrete product easily tolerates any extreme tests.
The secret of ultimate strength of reinforced concrete structures is hidden in the features of production:
- Improved solution recipe. For the preparation of concrete use only selected fine gravel( up to 10 mm), which is perfectly adjacent to a thick reinforcing mesh. A fine-grained impurity is a guarantee of the absence of air "pockets" in the finished product.
- Additional steaming. The preforms poured into the molds are sent to the steaming chamber for 8-12 hours. This accelerates the process of hydration of cement, contributes to a better fusion of all components of the solution.
- Voltage technology. Some types of reinforced concrete products( for example, slabs for seismically hazardous regions) should have a particularly high bending strength. To do this, in the process of preparing them, the reinforcing bars are pulled in the formwork by means of a jack( alternatively, they are heated by an electric current) and in this position they are poured with concrete and steamed in an oven. As a result, the finished element is able to withstand serious disasters.
- Straining cement. This special mixture recipe is used for thin-walled reinforced concrete structures subjected to high power loads. During the solidification process, the solution expands, as it were, "swells", in a molded form its pressure reaches a truly record-breaking level( up to 4 MN / m2).The material is also used for the preparation of extra strong reinforced concrete products with prestressing.
Conventional designation of reinforced concrete - reinforced concrete products( reinforced concrete products).But as the assortment of elements from this material is constantly replenished with new samples, each of them has its own recognizable abbreviation.
"World" of the variety of reinforced concrete products
Here are the most famous representatives of the "ZhBI dynasty":
- Plates for overlapping. These are ready-made floors / ceilings for a multi-storey building, the elements are the most requested "spare parts" in construction. There are such types of overlapping: hollow( PC), solid( PTW), ribbed( PRT).In each of these groups of reinforced concrete products there are subgroups, differing from each other with letter designations.
- Piles. These are the "legs" for the pile foundation, which are: driven( C), pressed( IED), screw( CB), shell( CT pipe).Accordingly, each kind of element in turn is subdivided into several subspecies( for example, integral and composite).
- Foundation blocks. Used for the rapid construction of a plate, columnar or tape prefabricated foundation. They are divided into wall( FBK), tape( PL and cushions), U-shaped( FPP) and blocks with through holes( VBW).Factories produce both massive elements( from 350 kg) and "mini-cubes" for self-construction( 30 kg).
- Rings for the well. These products( К) - the main building material for prefabricated reinforced concrete "reservoirs".With their help you can quickly build a well of any type.
- Road plates. This is a roadway pavement for large routes and aerodromes( CNG, PDG).They are installed on those sections of the road where heavy weight loads are expected.
In addition to large-scale types of reinforced concrete products, there are a number of small products for any construction needs. This and paving slab, and paving stones, and walls for the fence, and curbs.
Explanation of the "code" of reinforced concrete products
The letter abbreviation of the reinforced concrete product encodes: type, internal "filling"( density of the reinforcement, material) and the purpose of the element. But in the digital code, its linear parameters are hidden. To understand the scheme of encryption is quite simple.
Let's consider some examples:
- A well of reinforced concrete rings is being equipped - КС-7-5. So, a wall piece with a diameter of 70 cm and a height of 50 cm is used. As for its thickness, the elements are usually grouped according to this index( 8 mm, 10 mm, etc.).
- Foundation is being constructed from blocks FBS-12-4-6. The work is carried out with a wall block length - 120 cm, width - 40 cm, height - 60 cm.
All variations of the designation of products made of reinforced concrete are clearly fixed in SNiP.Each manufacturer in its catalog must adhere to the generally accepted nomenclature, but additionally submit a table with a breakdown of the technical characteristics of its product.