During the construction of buildings from foam blocks, bricks, natural and artificial stone, load redistribution over window and door openings is required. For this, a concrete jumper is used. Its bearing capacity is determined by the size and internal structure.
Main features and varieties
The concrete lintel increases the strength of the building, extends its life, preventing the collapse of the entire structure and openings. According to the principle of production, these products can be attributed to two varieties, the first of which is monolithic and manufactured at the construction site, while the second is a prefabricated one, which is produced industrially.
Prefabricated jumpers and their parameters
The precast concrete lintel can be squared, while its width does not reach 25 cm, as for slab jumpers, the mentioned parameter is more than 25 cm. Beam jumpers are L-shaped and are intended to support floor slabs on the product. You can also distinguish facade products that protrude beyond the facade of the building and are used for openings, the width of the ledge of the masonry of which starts from 25 centimeters.
Standard sizes
The concrete bridge can have standard dimensions that correspond to GOST 948-84. Thus, the limit values along the length can be equal to 10.3, but the maximum figure reaches 33.7 cm. As for the height, it can vary from 1.2 to 2.5 cm. The width varies from 1.4 to 2 9 cm
Door and window jumpers are mounted on Portland cement without fitting, this indicates that the product cannot be cut. If the opening has an excessively large thickness, then it can be blocked by several elements.
Specifications
Concrete lintels, the dimensions of which were mentioned above, according to state standards should be resistant to cracking, characterized by rigidity and high strength. Frost resistance of concrete must comply with F-35 - F-200. The concrete component must be strong and conform to the M-200 brand or higher. The moisture content of concrete should not exceed 13%. Products are fireproof and reinforced during production. JB jumpers have a technological bias, which indicates that the lower plane is slightly smaller compared to the upper. The deviation in width may be 8 millimeters or less. As for the deviation in length, it can not be more than 2 centimeters. Reinforced jumpers are earthquake-resistant and capable of undergoing a 7-point earthquake.
The cost of reinforced concrete lintels
The concrete lintel, the price of which can vary depending on the manufacturer, as well as the technological conditions, must have a quality certificate and certificate. When choosing products, the first thing you should pay attention to is the load that the element can withstand. It is necessary to take into account the brand of concrete. If we consider several manufacturers, then Uralstroymarket is ready to provide a jumper at a cost of 975 rubles per unit. In this case, the size will be 20.7 x 1.2 x 2.2 cm. For an identical product, Reinforced Concrete Products Kit asks for a price of 512 rubles, while RusGradStroy offers the same products for 813 rubles.
Marking
When buying products of the type described, it is important to pay attention to the marking, which decodes the dimensions and technical features of the jumper. A stamp is 3 groups of letters and numbers that are separated by a dash. The first group indicates the cross-section number, after which the jumper type and length are mentioned. The second group allows you to understand what is the design load and what class of reinforcement was used in the manufacture. The third group indicates the labeling of hinges, outlets of reinforcing bars and mortgages. It refers to earthquake resistance and the degree of density of concrete used in the production.
Jumper Features
Non-supporting jumpers can be mounted manually, but only if the height of the window or doorway is not more than 2 meters. As for the supporting jumpers, their installation is carried out by a crane. For the convenience of carrying out such work, holes are made in advance in the product, the diameter of which is 3 cm. They are sometimes replaced with mounting loops. Before laying, the jumpers are checked for damage.
The solution is designed to fill the resulting hollow spaces, forming seams.
Conclusion
When choosing jumpers, you need to pay attention to their quality characteristics, since each model is intended for specific purposes. That is why it is important to pay attention to the marking, the decoding of which can be carried out by you independently after reading the article. However, installation in many cases is not possible to carry out on their own, without involving construction equipment, the rental of which will have to be paid.