U-shaped blocks of aerated concrete: the best way to build
Ordinary reinforced concrete lintels, produced by factories, often cannot be used for buildings that have an unusual shape and original openings. In addition, another problem arises - the high price of the jumpers themselves and the cost of transporting massive products.
Aerated concrete lintels are free from all these disadvantages. They can be prefabricated or prefabricated monolithic.
Advantages, characteristics and purpose of the blocks
Tray and u blocks of aerated concrete can play the role of formwork, and also provide an opportunity to make jumpers of precast type or precast-monolithic.
Material advantages
- Easy installation. A small specific weight of the material (with good strength properties) makes it possible to save money without using special equipment and lifting devices. Aerated jumpers can be mounted manually.
- Exact dimensions (standard sizes), according to the parameters sounded in standards. Разновидности этих элементов можно применять, исходя из толщины стен. Их width точно совпадает с аналогичными параметрами обычных (рядовых) газобетонных блоков.
- The uniformity of supporting structures and built-in elements. They are made of the same material as the walls of the building. Due to this circumstance, the finishing of the building is facilitated and accelerated.
- Aerated concrete u blocks form protection against heat losses, and also prevent the creation of "cold bridges".
Note! These elements have dimensions of length / height of 60? 20 or 50? 20 cm and a thickness of 25 cm, 30, 37.5 and 40. This makes it possible to choose the size of the lintel corresponding to the partition or wall.
Purpose
U-shaped aerocrete blocks can be used for the following.
- As lintels of door and window openings of external walls and partitions having a width of 90/150 cm.
- As binding straps.
- As support for precast reinforced concrete floor slabs.
- As supporting elements rafters and mauerlatov.
Block properties
Below is a table of the main characteristics of products.
| Brand by density | D-500 | |
| Bulk density (normalized) | 500 kg per cubic meter | |
| Compressive strength class | B-2.5 | |
| Heat conductivity coefficient (dry state) | 0.114 W per 1 ° C | |
| Heat conductivity coefficient (humidity 8%) | 0.146 W per 1 ° C | |
| Heat conductivity coefficient (humidity 12%) | 0.162 W per 1 ° C | |
| Shrinkage of the blocks during their drying | not more | 0.3 mm per 1 m |
| Product class for frost resistance | 100-F | |
| Vapor permeability coefficient | 0.2 mg / w / w / Pa | |
| Heat resistance limit | not less | R-I/150 |
| Deviations from standard dimensions | ||
| height | ± 1 mm | |
| width | ± 2 mm | |
| length | ± 3 mm |
Transport and loading properties of the blocks are announced below.
| The size of the U-shaped block, in mm | The number of blocks per pallet, in pcs. | The volume of the pallet, in m3 | Pallet weight, in kg | ||
| length | height | thickness | |||
| 500 | 250 | 300 | 24 | 0.9 | 500 |
| 500 | 250 | 400 | 18 | 0.9 | 500 |
Jumper Installation
As already mentioned, jumpers of aerated concrete blocks in the shape of the letter U, can be installed in two ways.
Prefabricated structures
- Combined types of lintels are used to cover openings of up to 250 cm in length.
- При его монтаже, такой блок должен опираться на стены not less, чем на 20 см с каждой из сторон (если width проема до 5 м). Когда пролет равен 1.5/2.5 м, то конструкция должна иметь опоры с каждой стороны в 25 см.
- The instruction warns that tray blocks should be mounted on a hard and flat surface. It is necessary to connect them with each other with glue for aerated concrete.
- When the lintel is mounted on the outer wall, a thermal insulation layer of mineral wool or polystyrene foam is additionally installed.
- Further, assembled trays are laid with reinforcement bars or a volume reinforcing frame is welded. Then a concrete solution is poured into this peculiar formwork.
- It is necessary to select the reinforcement, the type of frame, the class of concrete, on the basis of which wall the bridge is placed on and how wide the opening is. Usually, reinforcement rods with a diameter of 8/14 mm and a solution of classes B-15 / B-20 are used.
Note! The optimal mobility of the concrete when the lintel is cast is cast (the cone shrinks more than 18 cm). This makes it possible not to condense the mixture with a vibrator.
Precast monolithic analogues
When it is necessary to block an opening 2.5 / 4 m wide, the best solution would be to build a composite monolithic jumper using aerated concrete blocks.
- Its production is carried out directly above the overlapped span.
- First mounted temporary support shield. Next, U-shaped trays are put on it, so that the outermost of them lean against the wall not less than 25 cm.
- With each other trays are connected with glue for aerated concrete.
- Then, by analogy with the production of prefabricated lintels, the structure is insulated, reinforced and filled with concrete.
- Support shield can be removed after 14 days.
- DIY laying of ordinary blocks on the lintel is carried out after the concrete has gained design strength.
Conclusion
Aerated concrete is a modern technological and comfortable building material. The construction of the walls of it is further facilitated by the fact that manufacturers produce special structural elements. Including tray blocks.
The video in this article will additionally tell about this topic.