Overlap plates according to GOST
Concrete and hollow core slabs - the most reliable and durable option for the construction of residential buildings. It is important to calculate correctly not only the load on the plate itself, but also the force with which it presses against the walls, foundation and supporting structures of the house. Inconsistency in the weight of overlap and endurance of the walls can serve as the main cause of the accidents of buildings.
That's why choosing such decisive materials and drawing out the draft of the project is not based on the traditional Russian "maybe", but strictly following the rules and regulations. In particular, the GOST specifies all the information regarding the requirements for reinforced concrete slabs in detail.
GOST 26434-85
At the same time, the principle of generating the product code will help to avoid tangling in the sizes of the overlapping panels of the producers. Take, for example, the code PC34-10: in this case the length is 3400 mm, and the width is 990 mm( PC means the slab).The width of 990 mm is carefully thought out and allows you to meet the required length when assembling the floor of reinforced concrete boards.
How to calculate the thickness of slabs
The most economical construction will be achieved if the materials and design are calculated taking into account the smallest possible loads. For this, it is possible to reduce the pitch of the supporting structures, so that the load on the overlap will be distributed more evenly. At the same time, an increase in load-bearing columns increases the cost of construction, and a decrease in the thickness of the slab reduces it substantially. Even in the most elite apartments, the step of load-bearing structures of 4.6 meters will organically look. This will allow to use without risk to people and building slabs with a thickness of 12.7 centimeters. Due to the reduction in spans, the consumption of steel reinforcement is reduced - the most expensive component of quality overlap.
Explanation of the image:
Co - the price of reinforcement and concrete;P is the step of supporting structures;О - fire resistance;Mo is the volume of concrete used;1 - building standards for filler from shale expanded clay;2-plate 12.7 cm;3 - the norm recommended by the Portland Cement Association, calculated by interpolating the indicators from the accepted building codes
It should be noted that the 12.7 cm thick overlay made of standard grades of heavy concrete meets almost all fire safety standards.
And yet, some rules dictate the use of floors between floors with a three-hour degree of fire resistance, which means that in such cases concrete with a lower weight or greater thickness is recommended.
What alternative overlap alternatives exist
Concrete slabs are not the only way out if you need to make supporting structures between floors. Let's consider alternative variants:
- monolithic overlapping - a rather laborious process, requires the installation of formwork, reinforcement, pouring concrete and removing formwork;It takes a lot of time to harden the concrete( at least 2 weeks) + in winter time it requires heating the room;
- wooden flooring is light, which is important for fragile supporting structures and weak foundation solutions, but special treatment is required from drying out, rotting and pests, plus this kind of floor is unstable, vibrating, which will not allow, for example, to tile the floors with tiles.
If you did choose the use of reinforced concrete slabs, remember that it will be easier to install them in a building of a straight form - without roundness and other decorative solutions.