The basis of any house is formed by a strong load-bearing frame made of vertical and horizontal elements. Its design can include walls, columns, beams and slabs. And if the vertical components of the system usually take on loads, then the horizontal ones, on the contrary, create a load mass. The most critical element of this type is the ceiling, which is implemented in the form of a slab or a beam crate. In order for the ceiling to stably hold its weight and cope with the tasks of the structural device, it is necessary to comply with the relevant technical requirements and regulatory rules during installation.
Basic ceiling slab classifications
Specialists identify two features of the classification of this design - purpose and technical performance. Classification by purpose separates the following overlaps:
- Ground. The first and base floor level of the common frame, thanks to which the first floor is separated from the foundation platform with grillage. In projects with basements alsothere is also an underground level of overlap.
- Interfloor. Ceilings in houses with several floors. As a rule, this is a structure that separates the first and second floors.
- Attic. Slabs or beam systems that separate the lower living floor from the upper attic or attic area.
As for the technical performance, the differences relate to the bearing part. It has already been said that both slabs and beams can form the basis of the structure. And here there is a classification according to the floor material used, which should be considered separately.
Reinforced concrete slabs
The structure is made of concrete reinforced with metal rods. However, today, even in floor slabs, thin fiberglass rods are sometimes used, which, with the same bearing capacity, are characterized by low weight relative to metal counterparts. Monolithic slabs are made directly on the construction site according to the principle of the formwork structure.
Another option for creating a tiled floor is prefabricated. This is a system of ready-made elements from which a solid frame is formed. There are prefabricated welded-type ceilings and hybrid ones. The difference between them lies in the connection methods. In the first case, welding conjugation of the floor components is used by means of a bond through metal reinforcing rods, and in the second case, the finished blocks in the fastening units are poured with concrete. The choice of a particular system is determined by the requirementsproject and installation conditions, but reinforced concrete spans are generally considered the most reliable option for installing the ceiling part of the frame.
Timber beam ceilings
The design is a series of equidistant beams, outwardly resembling a wall crate, only larger. Unlike slabs, beam systems after laying have several structural features. For example, openings between beams are saved, which can be used to give additional functions to the floor. For example, empty niches can be filled with heat and water insulators, as well as noise suppression. After filling the space between the beams of the ceiling, it is necessary to carry out the flooring. It is arranged with chipboard panels, closing the beam batten system. This flooring will form the basis for laying floor logs and future decorative coatings.
Slab sizes
There is no single floor size, but there are standardized modifications in a wide range of output formats. For example, the length of a tiled structure varies on average from 2400 to 6600 mm. The size interval between different formats is 300 mm. There are also models that go beyond this range - for example, plates with a length of 900 and 7500 mm, but these are already specialized designs. The coordinating dimensions of the ceiling in width are 1000-3600 mm with the same step. Mostmodels of plates with a width of 1200 and 1500 mm are common. As for the thickness, it is 220-300 mm. In turn, beam ceilings from timber can be used in frames with a span width of up to 5000 mm.
Technical and structural features of floors
Both beam and tile floors can have special devices in their construction for easy movement, reinforcement and laying of communication networks. For such tasks, even at the manufacturing stage, grooves, recesses, loops, inserts and other functional technical devices are provided. Hollow cylindrical niches with a diameter of 140-16 mm are created in tiled ceilings. On the one hand, they lighten the mass of the reinforced concrete structure, and on the other hand, they perform the function of stiffening ribs. To simplify the lifting in the plates, gripping devices are used. Their specific device is calculated at the order stage in accordance with the lifting scheme and conditions. These can be the same loops, and technological holes for the hook.
Requirements for structural reinforcement
According to GOSTs, reinforcing steel should be used to reinforce the floors. The specific grade of alloy and its parameters depend on design requests. For example, prestressed reinforcement is made of thermomechanical rods of class At-IV (VI), and hot-rolled reinforcement is made of rods A-IV (VI). In ceiling slabs, which are made according to the continuous formless method on longstands, it is necessary to use high-strength wire reinforcement or metal ropes. In the process of reinforcement and further installation activities, the exposure of embedded rods is not allowed. The only exception is the technological ends of the reinforcement, which are not planned to be released beyond the ends of the ceiling by more than 10 mm. But these protrusions must also be insulated with bituminous varnish or cement-sand mortar.
Technical and operational design requirements
Much in the calculation of floors depends on the specific parameters of the house and the external operating conditions. But there are also general technical rules that any construction of this type must comply with:
- Sufficient strength, which will eliminate the risks of deformation and deflection of the structure. By the way, at the interfloor ceiling slab, the average density of the concrete structure is 1400-2500 kg/m3.
- Fire resistance. There are different classes of fire resistance, and the most heat-resistant designs are used in cases of laying a chimney on the floor in the attic.
- Sound and heat insulation. There may also be different levels of insulation efficiency, but the minimum noise comfort and heat resistance in a residential building should provide all levels of overlap. Another thing is that in each case a material is selected that corresponds to the place of application in terms of protective properties.
- Special properties and characteristics. Special requirements may apply to steam and water resistance, gas tightness andbiological security, depending on the conditions of use of the structure.
Conclusion
The technical implementation of a ceiling slab is determined by many factors, some of which are based on general building codes, and some are based on specific design conditions. As a rule, in private houses, ceilings are made either with small-format reinforced concrete slabs or with a wooden beam system. To a large extent, the choice between these designs will be determined by the material of the main frame. Moreover, there are also hybrid variants of the floor system, in which different levels are organized by metal, reinforced concrete and wooden structures separately. The main thing is that the general principles of the frame structure are observed, which involve ensuring the reliability, durability and resistance of materials to dynamic and static loads.
