Reinforcement 12. Building reinforcement: production, weight, price

2024 Author: Howard Calhoun | [email protected]. Last modified: 2023-12-17 10:16

Reinforcement is a steel product that has the form of a long rod with a circular cross section. The main purpose of this type of rolled metal is to improve the quality of concrete structures. There are several types of fittings, each of which is produced in strict accordance with GOST standards.

Destination

Concrete is an extremely compressive material. The structures poured from it are able to withstand enormous weight absolutely without harm to themselves. However, unfortunately, this material is very fragile in tension, just as it is in bending. Due to this feature of concrete, many problems can arise during the construction of buildings and structures: cracking of the foundation and walls as a result of the forces of spring heaving, destruction of floors due to too high a vertical load, etc. The tensile strength of concrete is only 10-15 % compressive strength.

This problem is designed to solve metal fittings. The thermal expansion coefficient of steel is close to that of concrete. This makes it possible to use materials in the complex. The most demanded in low-rise construction is reinforcement 12 mm in diameter. Concrete structures reinforced with frames bound from it are characterized by high compressive strength and at the same time acceptable tensile strength.

When building foundations, which account for the main load during spring heaving, the use of reinforcement is a must. Often this type of rolled metal is also used in the construction of walls (strengthening masonry, upper stiffening belt). Reinforcement in the form of a grid is used when pouring floors and screeds. It is also used in the manufacture of concrete paths, blind areas, etc. In the construction of multi-storey buildings, as well as houses on problematic soils, reinforcement of 16 mm and thicker is more often used.

Among other things, this type of rolled metal also improves such an indicator as the fatigue strength of concrete, as well as the resistance of structures to mechanical stress from the outside.

Material of production

Since reinforcement is a very important element of reinforced concrete building structures, special requirements are imposed on its quality. The raw material for the production of rolled metal of this type is special reinforcing steel. To improve the mechanical properties, it is alloyed with manganese and silicon. Titanium and chromium treatment is carried out to give the reinforcement special strength.

Varieties by diameter

Reinforcement of different thicknesses can be used in construction. In this regard, there are certain standards set bySNiP standards. So, for example, for the foundations of buildings with very light frame-panel walls erected on stable soils, bars with a diameter of 10 mm can be used. In the construction of private houses of almost all other types, as already mentioned, 12 mm reinforcement is used.

Types by manufacturing method

Production of reinforcement 12 mm (steel), as well as rods of any other thickness, is carried out according to two main technologies:

• By hot rolling steel. Such products are called rod.
• By cold drawing steel. This is the so-called wire look.

The production of 12 mm rebar is not too complicated, but it requires the use of special equipment and strict adherence to all required technologies.

Finished frames and meshes are produced in specialized factories. The procedure for their manufacture includes the following steps:

• If the source material is supplied in reels, unwinding is performed.
• Fixing wire or bars in progress.
• The rebar is cut into pieces of the required length. This and the previous operation are performed on special straightening machines.
• Followed by the assembly of the elements of the frame or grid. This operation is performed on special welding machines. In some cases, the elements are connected by manual welding.

Sometimes reinforcing cages and meshes are also made right during the construction of buildings (usually low-rise). ATIn this case, the structure can be welded or wired. The first method is less labor intensive. When using the second, a more durable frame is obtained. The fact is that in places of welding, steel subsequently rusts faster.

Surface type

On this basis, only two types of 12 mm reinforcement are distinguished:

• Smooth, which is ordinary rods or round wire.
• Corrugated. On the surface of such reinforcement there are transverse (usually sickle-shaped) and longitudinal ribs. This design can significantly increase the adhesion of the frame elements to concrete.

Types by working conditions

The following types of reinforcement are commonly used in frames:

• distribution;
• working (actual bars 12 mm);
• montage;
• clamps.

According to the working conditions, 12 mm reinforcement is divided into:

• Tense. It is used when special strength of the concrete structure is needed (in seismic areas, in the floors of high-rise buildings, in parts of bridges subjected to vertical loading, etc.).
• Relaxing. Fits without pretension. Used in conventional concrete structures.

Rebar weight 12mm

When erecting small private buildings, the amount of rolled metal required is usually calculated in running meters. Manufacturers often sell rebar by weight. This may cause some difficulties in the calculations. In order to find out how many kilogramsreinforcement is necessary in one case or another, the weight of a running meter should be multiplied by the required length of the material. The first indicator depends on the type of reinforcement and is determined according to special tables.

Thus, the weight of 12 mm rebar (made in accordance with GOST) is 0.89 kg/linear meter. Suppose, for the construction of a house, 25 m of rolled metal is required. Therefore, you need to buy 25 x 0.89=22.25 kg of bars.

Marking and cost of fittings

Smooth rolled metal 12 mm is marked with the letter A1, corrugated without perforation - A3. Also, by marking, you can find out the method of manufacturing reinforcement (A - hot-rolled, B - cold-made) and the grade of steel used (numbers). The product can be supplied in coils or bars. For example, the designation of reinforcement "A3-A500C" is deciphered as follows:

• material has a corrugated surface (A3),
• made by hot rolling (A),
• steel grade - 3PS (A500C)

The price of rolled metal of this type depends primarily on its thickness, as well as on the brand. How much can rebar 12 cost? The price for rods of this diameter - hot-rolled (the most popular variety) - varies from different suppliers in the range of about 22-29 thousand rubles per ton. Of course, when buying, you should ask the seller for a certificate of conformity with GOST. The marking on the fittings is usually affixed already during the rental. If this was not done during the manufacture of rods and rods, their ends are marked with indelible paint. So, for example,steel A500C is marked in white and blue, A600C - yellow and white, etc. You can find out the exact match for other types of rod from special tables.

Thus, rebar - one of the most popular types of rolled metal on the market - can be produced in different ways from various steel grades, have a smooth or corrugated surface, be thick or thin. Rods of 12 mm are among the most popular varieties. When buying them, as well as when purchasing any other fittings, you should first of all pay attention to the marking and type of surface.