Wooden or reinforced concrete floors? Types of reinforced concrete floors Prefabricated reinforced concrete ceilings from panels.

The simplest type of monolithic reinforced concrete floor is a smooth single-span slab, the span of which is taken in the range from 1.5 to 3 mm; the thickness of the slab can be from 60 to 100 mm depending on the load and the span.

With spans of more than 3 m, a smooth slab is uneconomical due to its large thickness and significant dead weight. In these cases, floors are used in the form of a system of beams and slabs interconnected into one whole (ribbed and coffered floors).

Ribbed cover

Ribbed ceiling (Fig. 107, a) is a structure consisting of a mutually connected slab and beams. On fig. 107, b shows a diagram of a ribbed ceiling over a room 24 liters long and 16 meters wide.

Across the room are laid 3 powerful runs, called the main beams, based on the outer walls and the column. Along the room are the so-called secondary beams, or ribs, based on walls and girders. The span of the slab (the distance between the axes of the ribs) is 2 m. In general, the span of the slabs is taken from 1.5 to 3.0 m, their thickness is from 60 to 100 mm.

The normal span of a secondary beam, at which its height is acceptable in terms of the total height of the floor, is a span of 4 to 6 m. In this case, the height of the beams (including the thickness of the slab) can be approximately taken equal to from 1/12 to 1/16 of their span, and the width - within 1/8-1/12 of the distance between their axes. Since the main beam is usually taken larger section than for a secondary one, its span can be increased to 6-9 m. Thus, the ribbed ceiling has a rectangular grid of columns with rather large distances between them.

In ribbed ceilings, up to 50-70% of the total amount of concrete is spent on the slab. By reducing the distance between the ribs and at the same time their thickness, a thinner plate can be obtained. The desire to reduce the thickness of the slab in order to save concrete led to the creation often ribbed floors(Fig. 108).

For the installation of such floors, instead of formwork, a sparse flooring is laid from boards supported by girders supported by temporary wooden racks supporting forests. Ceramic or cinder-concrete hollow stones are laid along the boards, the transverse seams between which are filled with mortar.

Rows of stones are laid so that between them a space is formed for the construction of reinforced concrete ribs. Reinforcement is laid on top of the ribs and stones and the ribs and the slab are concreted. To protect stones from possible falling out, it is recommended to make their side faces corrugated or beveled.

The height of often-ribbed floors with spans up to 6.0 m is taken from 200 to 300 mm with a slab thickness of 30 to 50 mm. The width of the ribs is 60-120 mm with a clear distance between them of 250 to 600 mm. Often-ribbed ceilings have the following advantages compared to ribbed ones: they are more profitable in terms of concrete consumption, less wood is spent on the formwork, and the formwork design is simple. In addition, these floors have a slightly lower structural height and form a smooth ceiling.

Caisson floors

Caisson floors (Fig. 109) are ribbed structures in which the main and secondary beams are of the same height. In this case, rectangular or square recesses are formed on the ceiling, in French - caissons. Economically, coffered floors are less profitable than conventional ribbed ones, and their use is justified mainly by architectural considerations.

Beamless floors

In beamless ceilings (Fig. 110), a reinforced concrete slab (150-200 mm thick) rests directly on columns, in the upper part of which there are extensions called capitals. The grid of columns with a beamless ceiling is taken square or close to a square with a side size of 5-6 m.

It is advisable to use beamless ceilings for heavy loads, and also, if necessary, to have a smooth ceiling (for example, in refrigerators, slaughterhouses, garages, etc.).

Precast concrete floors

Prefabricated reinforced concrete floors have great advantages over monolithic ones. They fully meet the requirements of complex mechanization of building construction, make it possible to reduce the labor intensity of work, eliminate work on the installation of scaffolds and formwork, and also drastically reduce construction time.

When designing structures of prefabricated iron elements concrete floors it is necessary to strive to enlarge them, since this reduces the number of assembly operations for lifting and laying elements, and reduces the number of butt joints. The best option there would be a floor slab on the room so that the ceiling was smooth.

In prefabricated floor structures, it is also necessary to provide for all kinds of holes, grooves and channels for heating, water supply and sewerage and electrical networks.

Prefabricated reinforced concrete floors are divided into three main groups: beam, in the form of flooring (slabs) and large-panel.

Beam ceilings(Fig. 111) are made of T-beams and filling between them. As filling, a roll of gypsum concrete or lightweight concrete slabs with a thickness of 80 and a length of 395 mm, reinforced with wooden slatted or bar frames (for interfloor floors), or lightweight concrete slabs with a thickness of 90 and a length of 385 mm, reinforced with welded steel mesh (for attic floors) is used (Fig. 111, a). In order to isolate from the air transfer of sound, the gaps between the beams and the reel are sealed with a solution, and slag is poured over the pa-kat.

Instead of rolling, light-weight concrete double-hollow liner stones 250 mm high and 195 mm long are also used (Fig. 111, b). The gaps between the stones and beams are carefully filled with cement mortar. This creates some solidity of the overlap and increases its rigidity. It is also necessary to fill the seams to improve sound insulation.

To be able to be used in ceilings with different payloads of the same types of beams, different distances between their axes are set - 600, 800 and 1000 mm for slab rolls and 600 mm for filling from insert stones. At the same time, the width of the plate-rollers is 510, 710 and 910 mm, respectively, and the liners are 510 mm.

Elements beam floors have a relatively small weight and therefore they are used in buildings equipped with low-capacity cranes (up to 1 t).

Floor coverings consist of flat or ribbed elements of the same type, laid close and connected to each other by filling the gaps between them with cement mortar. The elements laid close to one another form a continuous floor structure. This type of floor does not require beams and consists of a load-bearing reinforced concrete part (usually textured at the bottom), a sound or thermal insulation layer and a floor structure. Supports for flooring are walls or girders.

The most common flooring used in the practice of modern construction are hollow flooring (Fig. 112) 160 mm high with spans up to 4 m and 220 mm with spans over 4 m. The floorings have longitudinal voids of a round (Fig. 112, a), oval- vaulted (Fig. 112, b) or oval section (Fig. 112, c). The diameter of the round holes is 160 mm when the decks are 220 mm high and 120 mm when the decks are 160 mm high.

The oval-vaulted openings are 350 mm long and 110 mm high in 160 mm decks and 165 mm in 220 mm decks.

Floors with oval voids in last years are not used due to the complexity of their production in a conveyor way.

The given thickness of concrete in floorings 5.6-6.0 m long with round voids is about 120 mm, with oval-vaulted - about 100 mm and with oval - about 80 mm. Thus, decks with oval-vaulted and oval voids are more advantageous than those with round ones.

Recently, instead of floorings with round voids, floorings with so-called vertical voids (Fig. 112, d) are used, which reduce the consumption of concrete by up to 15% compared to round-hollow ones. Vertical voids are formed during concreting, if channels are welded to the pipe liners used to form round voids. When embedding the ends of the floorings with oval-vaulted and oval voids into the walls, it is possible for the upper flooring slab to be forced through by the overlying wall. Therefore, these floorings provide for sealing holes from one end during the molding process (Fig. 112, 8), and from the other after molding by laying concrete inserts on the mortar into specially provided cutouts in the upper floor slab.

Flooring of a large area, which can cover entire rooms, is called floor panels. The absence of joints in such ceilings within the room increases their sound insulation from airborne noise, provides simplicity and more high quality ceiling finishes. In addition, floor panels can be factory made with a clean floor.

To ensure the normative soundproofing ability from airborne noise, single-layer structures of interfloor panel ceilings, made of heavy concrete, should have a weight of 1 m 2 about 300 kg.

When constructing split-type floors, which use the soundproofing capacity of the air gap between the upper and lower floor panels that do not have a rigid connection between them, as well as when installing layered floors, the normative soundproofing capacity can be achieved with a floor weight of 200 kg / m 2.

According to the design scheme (Fig. 113), the following types of interfloor large-panel floors are distinguished; with laminated floor, split type and with laminated floor and split ceiling.

Slab with laminated floor(Fig. 113, a) consists of a carrier, the lower surface of which serves as a ceiling, and a layered floor, including a layer of soft and elastic material that improves sound insulation from airborne and impact noise, as well as a hard base under the floors and a clean floor.

A separate type ceiling consists of floor and ceiling elements separated by a closed air gap that isolates the room from airborne and impact noise, while the floor element must be separated by soundproofing gaskets from the ceiling element and walls.

Overlappings of a separate type are divided into three groups:

1) separate floor of two load-bearing panels (Fig. 113, b);
2) from one bearing panel and a separate floor structure resting on it (Fig. 113, c);
3) ceiling with one carrier panel and a separate suspended or self-supporting ceiling (Fig. 113, d, e.).

Overlappings with a laminated floor and a split ceiling (Fig. 113, e) consist of a carrier panel rigidly connected to the walls, a laminated floor and a suspended or self-supporting ceiling structure.

According to the constructive form, floor panels are divided into solid (single-layer and layered), ribbed (with ribs up or down), hollow (with round or vertical voids) and tented.

Load-bearing single-layer solid panel(Fig. 114, a) is reinforced concrete slab constant section with a lower surface ready for painting, and an upper flat surface prepared for flooring.

Solid single-layer reinforced concrete panels have a thickness of 100-120 mm with a multilayer floor structure and 140 mm with a sticker on a linoleum slab on an elastic basis.

To cover large spans (6-6.6 l), recently, solid single-layer prestressed reinforced concrete panels 140 mm thick have been used, in which sound insulation from airborne noise is provided by the weight of the slab itself.

Load-bearing laminated solid panel(Fig. 114, b) is a reinforced concrete slab of constant cross section, the lower layer of which is made of stronger concrete, in which tensile reinforcement is located; the second layer is made of light, less durable concrete. In three-layer panels, the third, upper, layer also consists of stronger concrete (unreinforced or weakly reinforced).

Ribbed panels may be with ribs facing up or down. It is advisable to complete load-bearing floor panels with ribs upwards (Fig. 114, c) with the floor structure at the factory, which ensures a high degree of factory readiness and safety of the panels during storage in a warehouse and installation.

Bearing floor panels with ribs down are recommended for use in floors with a split ceiling and in floors with a layered soundproof floor and a split ceiling.

economical often ribbed panels, consisting of two vibro-rolling shells (Fig. 114, d), one of which forms the base for a clean floor, and the other serves as a ceiling. A continuous air gap and soundproof gaskets between the shells provide the necessary soundproofing of the ceiling.

Bottom panel with ribs upwards (ceiling panel), having a bottom surface ready for painting, is rigidly supported by bearing walls and serves as a horizontal rigidity diaphragm. The top panel with ribs down (floor panel), having a top surface ready for flooring, rests on the bottom panel through soundproofing pads.

In the floor panel in the operational position, according to sound insulation conditions, there should not be any rigid connections with the bottom panel and with the walls. Such panels are assembled at the factory; they have 4 mounting loops that fasten the upper and lower shells. After installing the panel, the hinges are removed and the rigid connection between the shells is removed.

The disadvantage of a separate floor structure of two often-ribbed vibro-rolling shells, as field studies have shown, is their unsatisfactory soundproofing qualities. Sound insulation deteriorates due to the appearance of shrinkage cracks in the shells, which occur as a result of the use of sandy concrete with a large consumption of cement, as well as due to the forced steaming of products. In addition, the small width of the supporting part of the upper shell (60 mm) causes the fibreboard gaskets to collapse and lose their elastic properties. Finally, the gap between the top shell and the wall, instead of filling it with insulating fibreboard often monolithic with a solution.

For this reason, more recently rational decision consider the construction of an interfloor ceiling in the form of a flat reinforced concrete slab 140 mm thick, the weight of which provides case sound insulation from airborne sound transfer.

Hollow core panels along with hollow decks are widely used in construction. However, the cost of these panels is relatively high. It should also be noted the poor performance of these panels in bending in a direction perpendicular to the direction of the voids.

hipped panel(Fig. 114, e) has the form of a slab framed along the contour with ribs facing downwards in the form of a cornice. The use of such panels, manufactured in the size of a room, makes it possible to exclude crossbars and other beam elements from the structural scheme of the building, and, due to their small thickness, to reduce the height of the floor without reducing the height of the room.

When installing reinforced concrete floors in sanitary facilities a waterproofing layer is introduced into the floor structure. To do this, over decking or panels are usually glued to bituminous mastic 1-2 layers of roofing material. In places of junction with walls or partitions, the waterproofing is raised up by 100 mm.

In recent years, glued waterproofing of floors in sanitary facilities has been replaced with a cement-sand screed 30 mm thick (from a cement mortar with a composition of 1: 3), closed in a 3% solution of sodium aluminate. Such a screed is quite reliable and more simple protection from water penetration through the ceiling than pasting with rolled material. They also use waterproofing screeds from cement-sand mortars with the addition of ferric chloride to the latter, which also reduce water permeability.

IN attic floors(Fig. 115, a) on top of reinforced concrete flooring or panels, first a vapor barrier is laid (from one or two layers of glassine or only leather on the corresponding mastic), and then a layer of insulation. Boiler slag and expanded clay are usually used as insulation. To reduce weight and labor intensity, slab heaters are also used (mineral wool slabs, fibrolite, slabs of cellular concrete).

In beam ceilings, thermal insulation is placed between the beams, and reinforced concrete beams are insulated, for example, with mineral wool mats (Fig. 115, b).

The use of slag as a heater in attic floors does not meet modern construction requirements. Delivery of slag and backfilling of the attic floor by hand is a very time-consuming and expensive operation. In addition, the weight of 1 m 2 of an attic floor insulated with slag is very large - 520-550 kg / m 2. If reinforced concrete floorings are used, in which load-bearing and heat-insulating functions are combined, it is possible to lighten the weight of the attic floor by 2 times and reduce the complexity of its installation.

When installing reinforced concrete floors above cold basements and undergrounds, it is necessary, as in attic floors, to provide for the laying of insulation. However, in this case, the vapor barrier should be placed not from below, but from above the insulation.

Promising types of floors are prefabricated armosilicate and ceramic floors. Compared to reinforced concrete, they are more economical in terms of cement consumption and total cost.

The peculiarity of the reinforced silicate floor structures (beams and slabs) is that instead of cement, local materials are used for their manufacture - lime and sand. Armosilicate products are processed in autoclaves at high blood pressure and high temperature.

Ceramic ceilings are laid from thin-walled hollow ceramic stones, from which they are made individual elements ceilings in the form of beams and panels. The stones are fastened together with cement mortar and steel reinforcement.

In modern capital construction of multi-storey buildings, reinforced concrete floors are most common, which are distinguished by valuable qualities - high strength, durability, fire resistance and water resistance. According to the method of execution, reinforced concrete floors are prefabricated and monolithic.

The main type of prefabricated interfloor reinforced concrete floors is floors made of slabs or panels. The structural basis of such ceilings are slabs or panels - large reinforced concrete elements (solid, ribbed, with voids) produced by factories reinforced concrete products. Plates are produced 6 m long, 0.8-1.6 m wide.

The most effective panels are "per room" size, the use of which allows to reduce the number of assembly units in the building, i.e., to increase the prefabrication of construction.

Panels and slabs are laid on walls and girders along a layer of cement mortar, and the depth of the ends of the panels resting on the walls must be at least 100 mm. Longitudinal seams between the panels must be filled with mortar grade "100".

To connect the ceilings to the walls and increase the overall rigidity of the building, the ends of the panels resting on the outer walls are fastened to the wall with anchors. When relying on internal walls panels are also interconnected with anchors.

When installing interfloor ceilings, a layer of sound insulation 20-50 mm thick is laid on the panels, consisting of slag, mineral wool or sand. Soundproofing can also be a 40-60 mm layer of lightweight concrete (slag concrete,). The floor in the interfloor ceilings is laid on a sound-proof layer (if it is hard enough) or on sound-proof pads from chipboard scraps or sheet rubber.

When installing attic floors on reinforced concrete panels or slabs, a layer of vapor barrier is laid, and then insulation. Vapor barrier protects the insulation from moistening with water vapor rising from the premises and condensate. As a vapor barrier, a layer of glassine is used, laid on the panels, or bituminous lubricant on the surface of the panels in contact with the insulation. As a heater in attic floors, a layer of expanded clay, granulated slag or mineral wool is used. In order to reduce labor costs for construction site mineral wool insulation is best used in the form of prefabricated prefabricated slabs. The thickness of the insulation layer in all cases is determined by heat engineering calculation. It depends on the calculated internal and external air temperature and on the insulation material.

side insulation layer attic space covered with clay-lime lubricant 20 mm thick to protect the insulation from destruction and weathering. In order for the lubricant and insulation not to collapse when walking in the attic, it is necessary to lay running boards at a certain distance from each other.

Prefabricated reinforced concrete floors can also be arranged in beam type. Such floors have to be used in cases where the construction site cannot be provided with reinforced concrete panels or if the load capacity of the mechanism installed at the construction site is insufficient to lift the panels. Reinforced concrete floor of the beam type consists of beams, inter-beam filling and floor. Beams (their length is from 2400 to 6000 mm) are laid on walls or girders parallel to each other at a distance of 600, 800, 1000 mm along the axes.

The depth of support of the ends of the beams on the walls or girders must be at least 150 mm, and the ends of the beams are connected to the wall using anchors. Inter-beam filling consists of rolling and soundproofing layer. Small-sized lightweight concrete (gypsum concrete, slag concrete, expanded clay concrete) solid or hollow slabs can be used as rolling.

Sound insulation laid on the reel is usually made of a layer of mineral wool. Logs (70 mm) are laid along the upper edges of the reinforced concrete beams and a wooden floor (30 mm) is laid so that a ventilation air gap is formed between the floor boards and the sound insulation.

When installing beamed attic floors, it is necessary to protect the beams from hypothermia with a layer of mineral wool or felt.

Due to the high labor intensity, reinforced concrete beam ceilings are used only in low-rise construction.

Monolithic reinforced concrete floors are beamed or beamless.

Beam monolithic ceilings consist of a slab resting on beams in such a way that a system of intersecting mutually perpendicular monolithic ribs is formed on the lower surface of the ceiling. Such an overlap is called ribbed. If necessary, you can arrange the ribs so that rectangular recesses of the same size - caissons - are formed on the ceiling. Compared to ribbed coffered floors, they have a more attractive appearance and their arrangement is justified from architectural considerations.

Beamless monolithic ceilings are a solid smooth slab 120-250 mm thick, based on walls and reinforced concrete columns, the distance between which is 5-6 m. The columns have widenings in the upper part - capitals that increase the supporting area of the slab. Due to the significant consumption of timber for, high labor intensity, and also due to the long periods of concrete hardening, which delay the production of related works in construction, monolithic floors in the mass construction of typical civil and industrial buildings rarely applied. Such floors are more expedient in non-standard buildings built according to individual projects.

Interfloor ceilings separating rooms from high humidity(sanitary facilities, washrooms, etc.) must be waterproof. To do this, waterproofing layers are introduced into the composition of the ceiling: in panel ceilings - along the upper plane of the panels, and in beam ceilings - along the concrete layer (hot bitumen coating). In addition, a waterproofing layer of two layers of roofing material on mastic is added to the floor structure over a 30-mm asphalt layer. This is laid on a concrete layer, directly under the cement screed. To protect adjacent premises from soaking in sanitary facilities, washrooms and similar premises, it is necessary to arrange 20-30 mm below the floors of adjacent premises.

Reinforced concrete floors are characterized by high strength, rigidity and good sound insulation. Depending on the design of reinforced concrete floors, they can be prefabricated or monolithic.

Precast concrete floors

Precast concrete floors are assembled from prefabricated reinforced concrete slabs manufactured in a certain range of sizes. For each manufacturer, this range may be different, but the length and width modules of the boards are the same for all manufactured boards. The length of the plates produced ranges from 2m to 7.2m, while the modulus of change in length is 100mm. That is, slabs with a length of 2.1m, 2.2m 2.3m and so on can be produced. The width of the plates can be 1m, 1.2m, 1.5m, 1.8m. The most common thickness of reinforced concrete slabs is 220mm. Plates produced by the industry have their own brand. For example, "PK 36-12-8t" will mean that the length of the slab is 3.6 m, the width is 1.2 m, the design load is 800 kg / m2, and "T" is the index of heavy concrete. However, it should be noted that the actual dimensions of the slab are actually slightly smaller than those stated in the brand and in the project for the house. So our plate will have actual dimensions of 3580 x 1190mm. This difference is due to the size of the gap between the floors and is necessary to maintain the design dimensions between the snap axes.

Reinforced concrete floor slabs are heavy from 0.7 to 2.5 tons, so a crane is needed to install them. An important nuance installation of a precast floor is that the laying slabs can be taken either from a truck or from a pre-stacked stack(s). And it is better to initially load or fold the slabs so that during the installation of the ceiling, the top slab is the first and the bottom slab is the last.

The support of the floor slabs on the wall or crossbar must be at least 120mm. Depending on the material of the walls, in case of insufficient strength, it may be necessary to install a reinforced concrete or brick reinforced belt, on which the slab will subsequently rest. The seams between the slabs are filled with concrete and carefully leveled.

Monolithic reinforced concrete floors

Monolithic slab with installed formwork

Monolithic reinforced concrete floors are erected directly at the construction site and form a single horizontal plane. The form of a monolithic floor can be any, which removes the planning restrictions on the design of the house, which are present in the case of a fully prefabricated concrete floor. The process of erecting a monolithic slab consists of several stages - formwork, laying the reinforcing cage, pouring cement, dismantling the formwork after curing.

Formwork for monolithic slabs can be made of edged board or plywood, the latter being the most preferred option as it forms a flat surface with fewer seams. However, no less good option there is also a metal formwork, but not everyone has the opportunity to use it. Flat formwork elements rest on horizontal wooden or metal beams, under which are placed vertical racks. It is highly desirable to use metal, height-adjustable racks, since with their help it will be easier to set the exact horizontal plane for pouring the slab. metal racks can be rented. After assembly, the formwork must be absolutely rigid and withstand not only the weight of the reinforcement and poured concrete, but also possible additional loads during the pouring process.

When assembling the reinforcing cage of a monolithic floor, it is necessary to ensure its even spatial geometry. The first layer of reinforcement should be raised above the formwork plane by 20-50mm. This distance is called the protective layer of concrete and may vary depending on the thickness of the floor and its design parameters. protective layer necessary to prevent corrosion of reinforcement and ensure fire resistance of the structure. In order to raise the reinforcement above the formwork, it is installed on special plastic clamps, which can be designed for different thicknesses of the concrete protective layer, reinforcement cross-section, and have a wide variety of shapes. The second layer of reinforcement is raised above the first with the help of supporting reinforcing elements.

Ceilings consist of a bearing part, which transfers the load to walls or individual supports, and an enclosing part, which includes floors and ceilings. According to the material of the bearing part, reinforced concrete floors are distinguished, according to wooden and steel beams, as well as armosilicate and ceramic. The cost of ceilings and floors in the total cost of the house reaches 20% of its total value.

The main material for the device of overlappings in modern construction is reinforced concrete. Reinforced concrete floors are divided into prefabricated and monolithic, concreted in the formwork. In recent years, mainly prefabricated and monolithic ceilings have been used.
Ceilings must meet the requirements of strength, rigidity, fire resistance, durability, sound and heat insulation, if they separate heated rooms from unheated rooms or from the outside environment. Ceilings in rooms with wet processes must be waterproof, and in rooms with gas evolution - gas-tight.

IN country houses from brick walls ceilings are used from reinforced concrete panels with round voids, the length of which is from 4800 mm to 6980 mm, width from 1000 to 2400 mm, height 220 mm, and also with flat ones - 2700-4200 mm long with a gradation of 300 mm, width 1200, 1500 mm , 120 and 160 mm thick. The panels are laid (fig. 1) on a layer of freshly laid masonry mortar 10 mm thick with embedding on supports of at least 120 mm. Through one panel (step 2400-3000 mm) they are connected to the walls with anchors with a diameter of 8-10 mm, which are attached to the hinges and led into the masonry 250 mm from the end of the panel, ending with a bend at an angle of 90 ° horizontally by 380 mm.

The seams between the panels are filled with cement mortar composition 1: 4 (by volume). Panels are installed using truck cranes.

Reinforced concrete floors

Such floors have a number of valuable qualities, the main of which are great strength, durability and fire resistance. When designing the structures of elements of prefabricated reinforced concrete floors, it is necessary to strive to enlarge them in order to reduce the number of installation operations and butt joints.

Precast concrete floors

Prefabricated reinforced concrete floors are divided into three main groups: in the form of flooring (slabs), large-panel and beam. Overlappings in the form of floorings consist of flat or ribbed elements of the same type, laid close; connect them by filling the gaps with cement mortar. Such floors consist of a bearing reinforced concrete part (usually textured from below), a sound or thermal insulation layer and a floor structure. The supports for the flooring are walls and girders. The most common are hollow decks with a height of 160 mm with spans up to 4 m and 220 mm - with spans of more than 4 m. The decks have longitudinal voids of circular cross section (Fig. 2, a).

In the manufacture of floorings with vertical voids, the consumption of concrete is reduced by up to 15% compared to round-hollow ones. Vertical round voids are formed using pipe liners (the liners are welded to the channels). Floorings that can cover entire rooms are called large panels. The absence of joints in the floor panels within the room increases their sound insulation and provides a higher quality ceiling finish.
To ensure standard soundproofing properties from airborne noise, single-layer structures of interfloor panel ceilings, made of heavy concrete, must have a mass exceeding 300 kgf / sq.m.

When installing separate type ceilings, which use the soundproofing capacity of the air gap between the upper and lower communication floor panels, as well as when installing layered ceilings, it is possible to ensure the normative soundproofing ability with the weight of the floor less than 300 kgf/sq.m.
By design, interfloor large-panel reinforced concrete floors can be with a layered floor, a separate type (with a separate floor, ceiling or from two separate load-bearing panels) and with a layered floor and a separate ceiling (Fig. 3). All these floor structures have a relatively small mass (less than 300 kgf / sq.m.); normative sound insulation is provided by a layered floor structure or the presence of a continuous air gap in the thickness of the ceiling.
Floor panels are made solid, hollow (with round voids) and tented. The load-bearing single-layer panel (Fig. 4, a) is a reinforced concrete slab of constant cross section with a lower surface ready for painting and an even upper surface.

Solid single-layer reinforced concrete panels 140 mm thick cover spans up to 3.6 m. To cover large spans (6-6.6 m), mainly solid single-layer prestressed reinforced concrete panels 14-16 cm thick or expanded clay-reinforced concrete 18 cm thick are used.

The hipped panel (Fig. 4, b) has the form of a slab framed along the contour with ribs facing downwards in the form of a cornice. Interfloor floors are also arranged from flat reinforced concrete panels with a thickness of 14-16 cm.

Prefabricated reinforced concrete interfloor floors ( fig. 5) beam type consist of tee beams and filling between them. The filler here is a roll of gypsum concrete or lightweight concrete slabs 80 mm thick and 395 mm long, reinforced with wooden slatted or bar frames, and in attic floors - lightweight concrete slabs 90 thick and 395 mm long, reinforced with welded steel mesh. The seams between the beams and slabs are filled with cement mortar and rubbed. Attic and basement floors must be insulated, interfloor soundproofing. For this, expanded clay or sand bedding, layered coatings with elastic gaskets are used. At the same time, it is desirable that heat and sound insulation be carried out not due to an increase in the weight of building structures.
Since the elements of beam ceilings are relatively light in weight, they are used in buildings equipped with low-capacity cranes (up to 1 t).
When constructing reinforced concrete floors in sanitary facilities, a waterproofing layer is included in the floor structure. To do this, 1-2 layers of roofing material are usually glued on bituminous mastic over decking or panels.

Monolithic floors

Monolithic ceilings are performed according to the established formwork. By transferring loads from the floor to the load-bearing walls, monolithic ceilings serve as an additional rigid frame of the building. Their device requires a certain professional skill and should be carried out according to the project under the guidance of a specialist builder. Making floors in place has its advantages. It does not require special transport and lifting equipment. Small-scale mechanization is enough to lift and move concrete. The basis monolithic floors the Monnier slab is laid, in which the reinforcement is placed in places of tension, that is, in the lower part of the slab. This is because steel has 15 times the tensile strength of concrete. The reinforcing frame of the slab should be located at a distance of at least 3-5 cm from the formwork walls so that concrete can fill this space. Length of span covered monolithic slabs, should not exceed 3 m. For plumbing pipelines, special metal or vinyl sleeves with an inner diameter larger than the pipeline being laid are installed in the ceiling. The gap between the sleeve and the pipeline is minted with tarred tow.

The disadvantages of monolithic ceilings include the need to install wooden formwork over almost the entire area of \u200b\u200bthe house. However, this does not mean that the formwork must be set all at once. Overlapping can be done in separate spans, transferring the formwork as the concrete sets.
The bearing capacity of monolithic ceilings is provided by reinforcement, the diameter of which must be at least 8-12 mm. In this case, intermediate joints of the rods along the entire length of the floor are undesirable. Minimum layer of concrete with outer side the overlap must be at least 2 cm. The span must be concreted in one working cycle.

Monolithic reinforced concrete slabs consist of a flat slab resting on walls and a system of beams (ribbed and coffered slabs) or on walls and directly on columns (beamless slabs).

Ribbed floors are a structure consisting of interconnected slabs and beams. The span of the slab (the distance between the axes of the ribs) is taken from 1.5 to 3.0 m, with a thickness of 60 to 100 mm.

Beams (or ribs) usually point downward, but if you want a smooth ceiling, they can be placed on top.

A coffered floor is obtained by crossing ribs of the same height evenly spaced in two directions; it is used for aesthetic reasons in the interiors of public buildings, as well as a means of lightening the large mass of the slab with large spans.

Beamless ceilings rest on columns through broadened capitals.

The listed floors are made at a construction site in a specially made formwork.

Recently, instead of monolithic structures, promising constructive building systems of prefabricated-monolithic buildings erected in the inventory formwork of the Grazhdanstroy type have been used.

OVERLAY PLAN		INTERFLOOR FLOORS ON WOODEN BEAMS WITH ROLLING BOARDS
		1- clean floor; 2 - lag; 3 - plaster; 4 - beam; 5 - cranial bars; 6 - roll-up shield; 7 - soundproofing (backfill)

		WHEN INCLUDED IN EXTERIOR WALLS	IN OPEN INTERIOR IN EXTERIOR WALLS

		IN OPEN INTERIOR WALLS
		1 - grouting; 2 - two layers of roofing on mastic; 3 - anchor; 4 - nails; 5 - open nest; 6 - overlay 50x6 mm
WOODEN BEAMS WITH SKULL BAR	RUN BOARD DESIGN
SUPPORTING THE END OF WOODEN BEAMS
		WOODEN FLOOR IN SANITATIONS
		1 - ceramic plates; 2- cement mortar; 3 - waterproofing; 4 - flooring from tongue-and-groove bars 50 - 60 mm FLOORS ON WOODEN BEAMS AND ROLLING PLATES FROM HOLLOW LIGHT-WEIGHT CONCRETE BLOCKS 1 - clean floor; 2 - lag; 3 - plaster or grout; 4 - roll-up shield; 5 - solution; 6 - lightweight concrete block

Rice. 47.

FLOORS

FROM WOODEN BOARDS	FROM GYPSUM CONCRETE PLATES

ATTIC FLOORINGS

INSTALLATION OF PARTITIONS OF THE 2ND FLOOR

INTER-APARTMENT PARTITION	INTERNAL PARTITION

Rice. 48.

OVERLAY PLAN			FLOORS ON REINFORCED CONCRETE BEAMS WITH ROLLING FROM LIGHT CONCRETE PLATES

			1 - clean floor; 2- lag; 3 - plaster or grout; 4 - reinforced concrete beam; 5 - gypsum concrete slab; 6 - solution
			FLOORS SUPPORT OF PARTITIONS


T-BEAM	LIGHT CONCRETE ROLLING PLATE	STONE - INSERT

			ANCHORING AND BEAMS SUPPORT INTERIOR WALL


NOTES:			EXTERIOR WALL
1. Reinforced concrete tee beams (BT) take the same section C (h\u003d 220) in length no more than 6000 mm and a multiple of 300 mm .; 2. Slabs (non-bearing) rolling - gypsum concrete 395x80 (h) unreinforced; carrier - 395x90 (h) reinforced (for attic flooring); 3. Beams are anchored in 1 - 2 pieces.

Rice. 49.

FLOORS

IN RESIDENTIAL ROOM

CERAMIC TILE FLOOR

(IN SANITATIONS)

ATTIC FLOORINGS

Rice. fifty.

FLOORS

FLOOR (BOARD, PARQUET, LINOLEUM)

IN RESIDENTIAL ROOM


CERAMIC TILE FLOORS	ATTIC FLOORINGS

* the components and dimensions of the ceiling above the cold basement are indicated

Fig.53.

OVERLAY PLAN BUILDINGS WITH LONGITUDINAL BEARING WALLS	BEARING ON A BRICK WALL AND ANCHORING DETAILS
INTERPRETATION OF THE MARKING OF PLATES: P - plate; K - with round voids; 4;6;8;10 - design load; 4;6;8 and 10 kN/m 2 (without taking into account the own weight of the plate); 60.12 - length and width in dm.	CONNECTION TO THE BRICK WALL (BASIC - WITH INCLUDED IN THE KDADKU)

SECTION OF A PLATE WITH ROUND COLUMNS
	JOINTS BETWEEN PLATES

	SUPPORT AND FIXING ON EXTERIOR WALLS


	SUPPORTING AND FASTENING PLATES TO INTERIOR WALLS

1 - wall; 2 - overlap; 3 - steel anchor; 4 - cement - sand mortar; 5 - concrete grade M 200; 6 - reinforcing concrete

Rice. 51.

SUPPORT OF MULTIPLE HOLLOW FLOORS ON WALLS

a,b - external large-block; c - internal large-block; g - external brick; d - internal brick; e - the same with channels

Rice. 52.

FLOORS OF LARGE-PANE BUILDINGS AND THEIR PARTS

a, b, - wiring diagrams of the floor with a small (a) and a large step of the walls (b); c - joint and fastening of floor panels by welding loops to each other while resting on internal walls; d, e - the same with the help of connecting rods

Rice. 54.

SOLID REINFORCED CONCRETE FLOOR PANELS OF LARGE-PANE BUILDINGS

a, h - lifting loops; f, i - embedded parts for welded fastenings of panels; g = reinforcing outlet at the corner of the panel; k = loop for attaching mounting struts.

Rice. 55.

SOLID REINFORCED CONCRETE FLOOR SLABS FOR RESIDENTIAL BUILDINGS WITH SMALL (2.7÷3.6 m) BEARING WALL PITCH (SERIES 1.143-2)

Rice. 56.

SOLID REINFORCED CONCRETE FLOOR SLABS FOR RESIDENTIAL BUILDINGS WITH LARGE (≤6.3m) BEARING WALL PITCH (ON SERIES 108)

Rice. 56.

RIBBED PRESTRESSED DECKING

SPAN 9 M

PRESTRESSED DECKING

TYPE TT-12 (12 M) TT-15 (15M)

1 - mounting loops; 2 - longitudinal ribs; 3 - transverse ribs

Rice. 58.

REINFORCED CONCRETE RIBBED PLATES OF TT- AND T-SHAPED SECTION FOR WALL PITCH UP TO 15 M (SERIES 1.242-1)

APPLIED IN FLOORS AND ROOFS OF PUBLIC BUILDINGS

LEAKED CONCRETE VENTILATED SLABS FOR COMBINED ROOFS WITH EXTERNAL DRAIN

WITH LONGITUDINAL CHANNELS Ø60; VIA 165 (SERIES 1.165-2)	WITH TRANSVERSE CHANNELS 50x50/2;

LEAKED CONCRETE SLABS (SERIES 1.165-7) FOR COMBINED ROOFS WITH INTERNAL DRAIN		PARAPET PLATES