Technology of pouring floor slabs with concrete. Monolithic concrete floor

Pouring a monolithic interfloor slab is not the easiest, but it is a truly universal and time-tested method.

In this article we will talk about the main design features and stages of floor construction, as well as types of formwork, including permanent formwork.

Typology of buildings and scope of application

The main areas of application of monolithic floors are buildings with load-bearing walls made of brick, block masonry or concrete panels, as well as domed houses. Requirements for the solidity of the floor may be determined by:

• non-standard building plan;
• the need to significantly increase the load-bearing capacity of the floor;
• increased requirements for hydro- and noise insulation;
• the need to provide an open layout;
• reducing costs for interior decoration.

Pouring is usually done after the construction of the walls of the first floor is completed. However, options for pouring monolithic floors already in buildings with roofs are possible, if weather or other conditions require it. In this case, I-beams are mounted on the masonry of the lower floor and a crown is poured along the perimeter of the load-bearing walls to the height of the ceiling. Also, to strengthen mechanical connections, with inside The crowns are produced with 40–50 cm embedded reinforcement. Its total cross-section cannot be less than 0.4% of the cross-section longitudinal section crown

Design calculations of the supporting structure

When choosing the span length, it should be related to the slab thickness as 30:1. However, when independent design There is practically no point in making a floor thicker than 400 mm, since load bearing capacity structure increases along with its own weight and static stresses. Therefore, the permissible load on homemade floors rarely exceeds 1500–2000 kg/m2.

The situation can be corrected by including I-beams in the supporting structure, laid on the concrete-lined masonry surface of the load-bearing walls. Another way to increase the span while maintaining relative freedom of layout is to support the floor on columns. With a monolithic structure thickness of up to 400 mm and a span length in four directions from the columns of up to 12 meters, the cross-sectional area of ​​the support is 1–1.35 m2, provided that the cross-section of the embedded reinforcement in the column is at least 1.4%.

Calculation of reinforcement of a monolithic slab

In general, the thickness of the slab is determined by the amount of reinforcing steel that is embedded in it. The reinforcement density, in turn, depends on the maximum permissible load and resistance to cracking. Avoiding special cases, we can give general example design demonstrating full compliance regulatory requirements with a sufficiently high safety margin.

In private construction, reinforced concrete is reinforced with reinforcement with a periodic profile of class A400, also known as A-III.

Diameter of rods in slabs of thickness:

• up to 150 mm - at least 10–12 mm;
• from 150 to 250 mm - at least 12–14 mm;
• from 250 to 400 mm - at least 14–16 mm.

The reinforcement is laid in two meshes with a mesh size of 120–160 mm, the thickness of the protective layer of concrete from the edges of the slab is at least 80–120 mm, and at the top and bottom at least 40 mm. The direction of laying four rows of reinforcement, starting from the bottom: along, across, across, along. For dressing, galvanized wire with a thickness of at least 2 mm is used.

Installation of different types of formwork

The formwork must withstand a load of 500–1100 kg/m2, including the dynamic impact of falling concrete. To create a formwork plane the following can be used:

1. Plastic sheets of reusable formwork.
2. Moisture-resistant plywood 17–23 mm thick.
3. OSB 20–26 mm thick.

The edges of the slabs must fit tightly to the walls; the use of formwork with gaps at the joints of more than 2 mm is not allowed unless it is planned to cover the surface with a waterproofing film.

Sometimes it is reasonable to make the formwork permanent, using profiled sheets, orienting them narrow shelf down. They are placed along the slab so that the waves during pouring form numerous stiffening ribs. The thickness is calculated from the bottom rib, thus saving the concrete mixture by 20–25%. In this case, the height of the ridge should not exceed a third of the total thickness of the slab. If the formwork is not planned to be removed, self-tapping screws with a rubber washer are screwed into it and tied with thin wire to the reinforcement.

Installation of formwork begins with the placement of racks: these can be either steel telescopic stands with a tripod and a unifork, or wood without defects with a cross-section of at least 100 cm 2. Each post should be connected to two adjacent 1-inch plank slants. The racks are mounted along the lines of the beams, the distance between which, depending on the thickness of the slab 150–400 mm, is:

• 190–240 cm with plywood thickness up to 20 mm;
• 210–260 cm with a plywood thickness of 21 cm.

In this case, the distance between the racks of one beam, depending on the gap between them, is:

• from 140 to 200 cm with a span of up to 150 cm;
• from 120 to 180 cm with a span of 160–210 cm;
• from 100 to 140 cm with a span of 210–250 cm.

The main beams are usually made of 100x100 mm timber. Secondary beams, which have a cross-section of 50% of the main ones, are laid across them in increments of 500–650 cm. If the formwork is made of profiled sheets, the pitch of the secondary beams is equal to 3.5 times the distance between the waves.

Vertical formwork is mounted from retaining panels attached to external wall building. Often, 80–100 mm thick aerated concrete blocks are laid around the perimeter to hide the ceiling belt.

Reinforcement and strapping

After installing the formwork, it is lubricated with an anti-adhesive compound and the installation of reinforcement begins. On the crowns and supporting ribs, the rods are tied into a square, maintaining the minimum permissible protective layer on all sides. The main floor mass is reinforced with mesh. The bottom layer is placed on plastic “crackers” that control the preservation of the bottom protective layer. The mesh is tied at the intersection of every third rod.

After tying the bottom mesh, intermediate clamps are installed on it every 100 cm in a checkerboard pattern. To strengthen the support, end clamps are mounted on the walls. These elements help maintain the design distance between two reinforcement planes.

The mounted upper mesh is connected to the lower connecting brackets. After installation is completed, the reinforcing structure should be as one whole and easily absorb the load from people walking on it.

Pouring concrete

Monolithic floors are poured with concrete grade B20-B30, prepared in factory conditions. Filling monolithic floors should be carried out in one stage, so filling the space in small doses is not recommended. If it is impossible to complete the entire volume of work at once, sections of the slab must be cut with a mesh with a mesh size of 8–10 mm.

The mixture can be supplied to the ceiling using a concrete pump or a large bucket lifted by a crane. After serving on top, the mixture is evenly distributed, vibration-set and left to harden.

Further actions

Concrete gains sufficient strength after 4 weeks, during which time it needs periodic wetting and protection from rain for the first 2 days. After drying, the formwork can be removed and the construction of walls can begin.

During the construction of a house, there is no way to do without installing a ceiling. This design limits the height of the room, insulates it from the penetration of cold air in winter, takes on loads from the roof or top floor. In modern technologies, a slab reinforced with reinforcement is most often used.

Description of types, design features, technical requirements

Depending on the location and functional purpose, concrete floors come in several types:

• basement;
• interfloor;
• attic;
• attics.

According to another classification, they are divided into solid and prefabricated. The first ones are made independently, pouring the mixture onto a prepared reinforcement frame. This method does not require the use of a crane to lift the slabs, but additional workers will be needed to install the formwork, tie the frame, and pour concrete.

Prefabricated systems are produced by laying standard panels the right size. According to their design, they come in three types: monolithic, ribbed, hollow. In private construction, the third option is more often used. Product dimensions: length – up to 7 m, width – 1.5, height – 0.22.

Taking into account the operating conditions, the following requirements are imposed:

• strength and rigidity exceeding the design load (it is defined as the total weight of the slab itself, screed, furniture, and other things);
• high level of sound insulation;
• fire resistance;
• wall thickness under concrete blocks not less than 200 mm.

Concrete has high thermal conductivity, to reduce which it is recommended to insulate it, for example, with mineral wool.

Installation instructions

Preliminary preparation of the structure and slabs helps to lay the finished concrete floor with your own hands.

Scheme of preparatory work

1. To ensure that the panels are in the same plane, the upper end of the load-bearing walls is checked for horizontalness. This can be done in this order: 30-40 cm before the end of the laying, markers are applied to the wall using a laser or liquid level, and then the finishing brick rows are checked with a tape measure. The top row is positioned so that the bricks are oriented towards the inside of the room.

2. Most often, the edge of the box is aligned differently - the perimeter of the upper edge of the walls with reinforcement is concreted. Due to this, the brick or block structure is further strengthened. At a certain level, the masonry leaves an empty space for the armored belt. The depth of support (overlap) of the ceiling depends on the total thickness of the slab together with thermal insulation. Typically the panel extends into the wall by 70-120 mm.

The scheme for pouring an armored belt is similar to laying a foundation: the formwork is installed, a frame of reinforcing bars is made inside it using welding, and the mixture is poured without crushed stone. The design of the belt for the plinth is made faster: simply add additional formwork along the outer edge of the foundation.

3. Before installing the slabs, be sure to close the voids at their ends. If this is not done, when placing the wall of the upper floor on the edge of the ceiling, it may collapse. Concreting the joints between the slabs will not produce results: the mixture will flow into the holes. It is not difficult to close the cavity - half a brick is inserted into it and sealed with mortar.

4. Prepare a site for lifting equipment. This is an area with dense soil, otherwise the crane will get stuck in soft soil. To ensure its stability, temporary placement of road panels on the site is practiced. It is advisable not to place the crane close to the pit to prevent the collapse of the soil or the sliding of heavy equipment.

Laying technology

It will not be possible to install the ceiling yourself; the process usually involves three installers. One worker connects the slabs, the other two correct them as they are lowered.

1. On reinforced belt Apply a fairly thick concrete mixture (layer thickness at least 2 cm).

2. The crane operator lowers the panel, holding it by tensioning the sling ropes. In a suspended position, it can be easily moved in the desired direction using a crowbar.

3. Compensation cut. It is necessary if one slab covers several spans. Conventional structures work in bending and must rest on two short ends. If intermediate supports are installed, tensile stresses arise in the upper part of the floors. Since there is no reinforcement there, cracks may appear. To relieve stress, use a grinder to cut a groove, placing it above the intermediate support. Subsequently, a crack will appear at the site of the slot.

4. Anchoring. This is stitching with reinforcing wire: it is threaded through the mounting lugs, tightened, and then welded. The scheme is usually laid down in the project; if it is not there, it is used standard option. For load-bearing walls there is at least 1 anchor for every 3 linear meters; for non-load-bearing walls, anchors are removed from all outer loops. The end plates are sewn together with diagonal anchors.

Inter-tile gaps (rusts) are filled concrete mortar, due to which the structure becomes monolithic and durable.

During installation, sometimes you have to adjust the dimensions. The optimal overlap on the wall is no more than 120 mm, and the maximum permissible value is 250. Increasing this parameter changes the design of the ceiling, and as a result, cracks may appear on it. The panels are shortened in the following way:

• mark a cutting line, place a block under it - its thickness should be such that the edge to be separated is suspended;
• According to the markings, make an incision with a grinder, use a sledgehammer to split the concrete above and below the voids;
• break partitions;
• metal reinforcement is cut with a grinder, leaving a couple of millimeters - this residue is broken with a sledgehammer (otherwise the stressed reinforcement may pinch the disc of the grinder).

If the size is insufficient, the gap near the wall is filled with bricks.

How to make a ceiling yourself?

The frame is made from edged boards(thickness 25-35 mm), plywood (thickness from 20 mm) or rent.

1. Install the formwork. Its dimensions should be such that the edges rest against the walls without gaps. The position of the structure is checked using a level. Cover it with waterproofing film.

2. Reinforced. Typically, rods with a diameter of 12-14 mm are used for the frame. First, longitudinal and then transverse elements are laid (cell 12-15 cm), tied with wire. The upper mesh of the frame is made in the same order, the joints of the rods are arranged in a checkerboard pattern, and the ends of the rods are placed on the load-bearing beams.

3. Preparation of concrete. Volumetric proportions of its components:

• sifted sand - 2 parts;
• crushed stone (gravel) – 1 part;
• cement M400(500) – 1 part;
• water.

Pour enough water so that the solution resembles liquid sour cream in thickness.

4. Filling. All cavities are carefully filled with the mixture, “smoothed” with a shovel, removing air. For the finishing fill, make a thicker mixture and lay it down. The thickness of the layer is 2-3 cm less than the final size of the overlap. After a couple of days, the set composition is covered cement-sand mortar medium thickness, level with the rule to an ideal plane.

The solidifying monolith is periodically watered and covered with film in hot weather. On the 10th day, the formwork is removed and allowed to gain strength for 3-5 weeks. After this, you can begin the next stage of construction.

It is important to install the interfloor ceiling with your own hands correctly, using construction technology step by step. It is necessary to delve into all the details of the construction of buildings.

At the first stage, it is important to determine the thickness of the main load-bearing walls of the first and second floors; the thickness of the future floor will depend on this. According to the standard for houses made of brick or aerated concrete, the interfloor ceiling can be installed from 15 to 20 cm; in houses made of more fragile materials, the thickness is reduced. Technology interfloor ceilings depends on the selected materials, height future design and the weight of the entire structure.

Formation and installation of formwork

start with formwork formation. It is installed between floors and is designed to securely secure cross beams. If there are old wooden planks it would be appropriate to use them. Having initially formed the covering from the boards, it is necessary to install a support. Stable logs are often used. A layer of waterproof plywood is laid on top of the formed structure. Next, the quality of the structure is checked for sagging. When eliminating defects and bends, they must be corrected immediately. In the future, the structure must be stable, able to withstand the additional load of furniture, distributing the load.

The interfloor covering device is divided into several main types:

• Reinforced concrete;
• Monolithic;
• Prefabricated;

Do-it-yourself reinforced concrete interfloor slabs are popular in buildings made of stone and brick. A special feature of the design is the laying of hollow panels. When seams are formed, they are completely filled with mortar. The disadvantage of forming floors reinforced concrete type is the massive weight and the need to use lifting equipment. In addition, the slabs have a standard size. With a house perimeter different from standard project, it will be difficult to correctly install the support of each slab.

Do-it-yourself wooden interfloor ceiling erected if you want to save money and time on construction. At the same time, it is important to correctly determine the type of ceiling and the ability to carry out installation without the involvement of additional equipment, renting forklifts and a team of specialists.

Monolithic ceiling. Main characteristics

Interfloor covering arrangement monolithic type represents a homogeneous solid structure, the array of which is distributed onto load-bearing walls. The use of a monolith has an undeniable advantage in that there is no need to use construction equipment. This coating is effective in that it makes it possible to implement modern architectural solutions, created by yourself at no additional cost. Before starting installation, it is advised to prepare construction beams that will serve as support. The steel surfaces of the beams are installed on wooden partitions.

Typical formwork includes the following elements:

• Special telescopic type stands;
• Holding tripods;
• Flooring;
• Basic moisture-resistant plywood;
• Frame and fittings.

The nuances of laying reinforcement with your own hands

Installation of interfloor ceilings carried out whenever possible without touching the surface of the formwork. The dimensions of the fittings range from 6 to 12 mm. At the same time, the structure is secured with certain clamps. The formed frame leaves cells of 10*10 cm. Wire is used to tightly bind the frame to the cells. Beams can be used various types from wood to aluminum. Next, the entire surface of the layer is densely filled with mortar, forming a homogeneous surface. The disadvantage of forming a reinforced floor is the formation of beams along the entire perimeter of the structure at minimal distances.

It is quite difficult to completely fill the ceiling with your own hands. The main nuance is to carry out the filling layer no more than 10-12 hours from the previous one. To create a uniform layer, the solution should not be allowed to dry completely. The technology of interfloor slabs makes it possible to obtain reliable adhesion of the monolith to the surface of the floor and mortar, holding the entire structure together. This method of creating a ceiling with your own hands is the most reliable, safe and easy to install. Complete hardening of the entire layer occurs no earlier than 28 days from the moment of the last pouring. Uneven drying leads to subsequent destruction of the surface, the formation of chips, cracks and additional dust. If it is necessary to eliminate the resulting defects, it is important to simultaneously fill the entire surface with a small amount of water and leave until completely dry.

Prefabricated monolithic type floors and their differences

The prefabricated monolithic type of flooring is the most relevant and in demand in the cottage-type construction market. The combination of support beams on one side and hollow blocks on the other has many advantages. The construction of interfloor floor beams must be uniformly filled with concrete and interfloor structure ready. Weight standard design quite low and amounts to no more than 19 kg per square meter. In terms of time, it is somewhat more difficult to produce a prefabricated monolithic floor, but there is no need to rent lifting equipment and all stages can be carried out independently. The entire structure is reinforced with wire no more than 6 mm in diameter.

Removal of formwork and installation of interfloor ceilings

When installing the main floors, the formwork is removed. Removal of the side surfaces is permitted in the case when the main overlap has completely frozen and formed robust construction. It is necessary to carefully check the entire surface from all sides.

Strength concrete structure determined by indicators:

• Load-bearing elements whose span is less than 2 meters account for 50%.
• Slabs with a span of 6 meters or more – 70%.
• Reinforced types of structures no more than 25%.

How to determine the strength of hardened concrete of an installed interfloor slab?

The concrete surface increases the strength of the coating from the moment the last layer is poured over time:

• 3rd day strength is about 30%.
• Day 7 increases to 60%.
• Day 14 is 80% or more.
• Day 28 is around 100%.
• Day 90 increases by 30%.

The duration of hardening of the concrete floor depends on the air temperature and humidity level environment. There are special additives that help speed up the hardening process of concrete on the surface of the floor.

Installation of interfloor ceilings can be labor-intensive; if difficulties arise, InnovaStroy specialists recommend contacting experienced craftsmen.

Do-it-yourself wooden interfloor ceiling

Wooden ceiling structure responsible for the formation of sustainable flooring the upper floor and a flat, reliable ceiling of the lower floor. The main mass is taken up by the load-bearing walls of the building. The installation of wooden interfloor slabs is most popular and in demand in modern construction country houses. Due to the ease of construction, the quality of the resulting flooring, environmentally pure materials and economical expenses. Wooden blocks tightly connect the building elements, exerting a horizontal load on all the main supporting walls.

Advantages of installing wooden floors

• Increased level of thermal insulation;
• Preservation of the acoustic properties of the room (if necessary);
• Simplicity and ease of installation with your own hands;
• Carrying out work in any weather conditions;
• Use of any type of ceiling: basement, interfloor, attic, attic.

When using wooden floors in areas prone to moisture accumulation (bathroom, basement, pool area, baths, etc.), it is recommended to use an additional level of waterproofing material.

General characteristics and construction of wooden interfloor slabs

Installation of interfloor slabs using wooden beams requires attention to the possibility of bearing weight. Own weight wooden covering is about 250 kg, while the weight of the additional load is taken into account at least 200 kg.

When choosing beam sizes, you must clearly determine:

• Beam thickness (standard: at least 5 cm);
• Height 15 cm or more;
• When laying wooden beams in increments of 50 meters or more, it is necessary to use a mineral-type insulating material.

List of necessary tools for installing ceilings with your own hands:

• Availability anchor bolts;
• Keys;
• Staples;
• Hammer;
• Screwdriver;
• Keys;
• Strong rope;
• Nails;
• Wood hacksaw;
• Roulette;
• Axe;
• Rigid construction cord.

Mastering the stages of technology, necessary tool Installation of the interfloor ceiling is quite easy. Installation wooden floors begins with laying the timber. Professionals advise using a glued type with a length of 12 meters or more.

Differences between wooden ceilings:

• Used when creating individual design of cottages .
• The cross-section of the material used depends on the width of the opening and the weight of the future structure, the ability to support the load of the building’s foundation.
• When purchasing material for the formation of interfloor ceilings, it is important to pay attention to the quality of the timber. Additional drying for more than 4 months and antiseptic treatment will allow you to maintain the original quality for a long time.
• If wood becomes suppurated, chips or cracks form, timber should not be used!
• All dimensions must be checked and adjusted to the required ones. The use of beams and bars of different levels is not recommended.
• Fire safety wood flooring required additional processing to form a stable impact of open fire.

Sometimes craftsmen recommend using roughing bars, which are installed on the edge of the beam elements. Next, a roll is formed and a dense rough coating is formed. Ventilation arrangement also plays a significant role in creating a cozy interfloor ceiling. Free circulation air flow between floors allows you to maintain a comfortable climate inside the building.

The InnovaStroy company specializes in the construction of houses according to individual orders"Full construction". High-quality interfloor coverings are the main task of creating comfortable multi-level housing.

Video existing species do-it-yourself interfloor ceilings, offered for viewing by the company InnovaStroy.

During the construction of houses, garages, cottages, and other structures, a stage comes when it is necessary to perform floors. The ceilings can be interfloor or ceiling, made of wood, using wooden beams, using concrete slabs or by pouring concrete. Each of these floor installation methods has its own legal right, existence, supported by the economic feasibility of using a specific option in each individual case. In this article, we wanted to talk about a specific case, namely the pouring of concrete interfloor (ceiling) floors. Before we talk about the methods of installing these floors, we wanted to touch on the topic of the use and installation of poured concrete floors, let's talk about their feasibility and advantages relative to other similar floors.

Advantages of poured concrete floors (monolithic concrete floors)

First of all, monolithically poured concrete floors should be considered as an alternative to slab floors. Wooden floors are too different from concrete-monolithic floors, first of all in price, monolithic ones are much more expensive, secondly, in strength, they are much stronger, thirdly, in durability and other not so significant differences. That is why it is worth comparing, first of all, with slab floors. Thus, in some cases, monolithic (concrete) floors are cheaper, which is an undeniable advantage, and at the same time they have similar strength properties. Another important advantage is that the fillers monolithic concrete ceilings can be made in any way complex shape, almost anywhere, which is sometimes impossible for standard, factory-made concrete products.

Example of installation of concrete, monolithic floors

Next, we give a specific example of installing concrete floors. IN in this case, This special example, possible improvements that could be made to improve the quality of the overlap, we will describe how alternative solutions. So, first of all, it is necessary to build a support for the poured concrete mixture and formwork.

After this, it is necessary to install the fittings.

It is best to carry out installation using mounting wire and lay two layers of lattice.

One reinforcing grid should be at the bottom, the second, laid through the “frogs,” should be at the top. Such a monolithic floor will more correctly perceive the bending load, due to the operation of the reinforcement in the most stressed places, which will significantly increase the strength of the floor.

Afterwards, we begin pouring concrete. It is best to buy the planned volume of concrete for this operation in order to carry out the entire pour at one time, since only in this case can you guarantee equal strength of the entire monolithic floor structure.

Also, you should not pour all the concrete into one place to prevent subsidence and collapse of the floor formwork. It is best to supply the concrete mixture evenly over the entire area; in extreme cases, quickly distribute it over this area using any alternative method.

The final stage will be holding the concrete mixture under certain conditions (temperature and humidity), which will ensure technological hardening of the mixture and its quality.

So, you can read in more detail about the process of hardening the concrete mixture in the article “How to pour concrete screed floor." Afterwards we dismantle the formwork, and our concrete floor is ready for use.

Calculation of formwork holding monolithic, concrete floors during pouring

Someone with a specific construction background can install a concrete floor based on their life experience, or as they say “by eye”. We want to offer you another, albeit not an institute calculation, but which to a high degree will become yours successful pledge successful work.

Calculation of formwork for this type of floor should be done according to three main parameters:

1. For the longitudinal load on the supports holding the formwork. Initially, it is necessary to calculate the cross-section of the supports for the holding formwork.

How to pour the concrete floor between the floors of a private house yourself?

Is this value not so critical? as subsequent parameters, which is why you most likely will not have problems with it. σ = N/F ≤ Rс where σ are the internal normal stresses arising in the cross section of the compressed beam, kg/cm2; N – mass of our formwork and poured mixture, kg; F is the cross-sectional area of ​​the column cm2; Rс — design resistance wood compression by yield strength, kg/cm2. (For pine, the calculated resistance is 140 kgf/cm2)

2. For bending supports under load. Also, do not forget the factor that the bending rigidity of the beam changes with its length. So, as the length of the holding beam increases, its flexibility also increases, and its rigidity decreases accordingly. In order to take this factor into account, it is necessary to take the cross-sectional area of ​​the beam with a correction factor φ

σ = N/φF ≤ Rc

the coefficient will depend on the ratio of diameter to length; to facilitate calculations, it can be taken from the series below

L/d = 5 10 20 30 40 50
φ = 0.9 0.85 0.5 0.25 0.15 0.08

3. To ensure the integrity of the formwork base The last thing you should pay attention to is the strength of the retaining formwork onto which the concrete will be poured. So the formwork must withstand not only the static mass of concrete, but also the dynamic load during its pouring. Also, do not forget about the possible temporary overflow of concrete to a specific local place and the weight of the worker who will distribute the concrete in it. As a result, the permissible thicknesses of plywood formwork, with a margin of 1.5, with a span of no more than 1 m, can be taken from the series below.

Plywood thickness 18 mm 21 mm

Thickness of the poured concrete floor layer up to 9 cm up to 12 cm

Now you can not only pour the concrete floor, but also pre-calculate the auxiliary technological elements for its installation.

Fill the interfloor ceiling correctly

• Installation of formwork
• What types of floors are there?
• How is the reinforcement installed?
• When should formwork be removed?
• Determining the strength of concrete
• Let's calculate the cost and expenses

It is very important to fill the ceiling between floors correctly.

After all, it will be a reliable floor of the first floor in your house, and will also be a durable ceiling that will not sag under any weight. ground floor. We will look step by step at how you can properly make monolithic ceilings or a floor between floors with your own hands and what we will need for this.

Structural diagram of a prefabricated monolithic floor.

Firstly, we will need skillful hands, beam, concrete, since we are considering the option of covering in a private brick or block house, therefore, to successfully complete this task with your own hands, you need to delve into all the details, because we are going to make the ceilings with our own hands.

First, we need to determine the thickness of the walls, since the thickness of our ceiling between floors will depend on this. Usually, for walls in a private house made of bricks or blocks, a floor thickness of 15 to 20 cm is used, but for thin walls you cannot use such a floor thickness, and it would be better to use a completely different option.

Installation of formwork

The next step will be formwork. It is installed between floors and is designed to secure the beam. When making formwork with your own hands, you can use old boards. Having laid the boards, they need to be supported from below with something, for example, logs. This will prevent this wooden floor from sagging. You can put plywood (waterproof) on top of the laid boards. Nessesary to use building level to determine surface unevenness so that our wooden flooring turns out smooth and, in cases of sagging, eliminate this defect. This method of pouring is called beamless.

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What types of floors are there?

Table where you can compare different types floors and choose the most suitable one for yourself.

There are reinforced concrete, monolithic reinforced concrete and prefabricated monolithic floors.

The former are especially popular for covering in brick houses. For their installation, solid or hollow-core panels are usually used, which are laid on cement mortar, the seams between the slabs are filled with mortar.

The disadvantage of this method is the need to use lifting equipment, standard sizes ready-made slabs are also a disadvantage, as they may not always fit the size of your home. The advantages of this method are strength reinforced concrete slabs, and the fact that concrete is not afraid of dampness, unlike wooden floors.

Monolithic concrete floors are a solid slab that rests on load-bearing wall. The advantage of this monolithic structure is the ability to carry out work without loading and unloading technical work, while the concrete surface is more durable, sealing joints is not required. More this method makes it possible to resort to bold architectural solutions.

To install this ceiling, it is necessary to use steel beams that are installed on wooden formwork.

This formwork includes several components: a unifork into which the beams are inserted, the beams themselves, telescopic posts that are supported by tripods, flooring and plywood. Sheets of plywood are laid on the formwork with a wooden floor, which serves as the basis for further pouring the concrete floor of the first floor. Next, a frame made of reinforcement is installed.

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How is the reinforcement installed?

Fire resistance limit reinforced concrete floors- 60 min; wooden floors with backfill and lower plastered surface - 45 minutes; wooden floors protected with plaster, about 15 minutes; There are even fewer wooden floors not protected by fireproof materials.

The reinforcement is laid in such a way that it does not come into contact with the surface of the formwork.

Reinforcement will require 6-12 mm.

How to make a reinforced concrete floor yourself?

For this purpose, special clamps (chairs) are used. The laid reinforcement frame should consist of cells measuring 10x10 cm. Using wire, the reinforcement frame is tied together with your own hands. In this method of flooring, you can use not only wooden floors, but also aluminum beams. Everything is ready, now all that remains is to fill the entire floor area with the solution.

The disadvantage of this type of construction is the need to install wooden formwork over the entire area of ​​such a floor.

Since we are going to fill our prepared surface with our own hands, we may need crane or a special trolley with an opening bottom. The concrete floor must be poured correctly. After all, you won’t be able to pour it quickly with your own hands, and therefore we need to take into account that the intervals between pours should be no more than 12 hours so that the solution does not have time to dry out, otherwise there will be no monolith, since the solution will not bind together.

Complete binding or adhesion of the solution occurs in approximately 3 to 4 weeks or 28 days. Uneven drying of the solution leads to cracks. If this happens, it is necessary to water the surface with water.

Prefabricated monolithic floor covering is the most modern device floors.

In this type of flooring, the space formed between one beam to another is filled with hollow blocks.

When all the spaces are filled with such blocks, all that remains is to fill the entire area of ​​this structure with a concrete solution. This type The structure can be assembled with your own hands without the use of lifting equipment, since the weight of 1 meter of beam is 19 kg. In terms of time and installation method, this flooring is more labor-intensive than other types of flooring. Before pouring this design, it must be reinforced with wire 5-6 mm in diameter.

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When should formwork be removed?

Scheme of small-panel collapsible formwork on frames for monolithic floors.

After meeting certain requirements, the formwork is removed from concrete monolithic structures. The side elements of the formwork, which are least exposed to the load from the weight of the monolithic structure, are allowed if concrete covering reached its maximum strength. It is worth being more careful when removing the load-bearing formwork of monolithic concrete structures.

This action must be performed when all standards of achievement are met. concrete pouring, the so-called design strength: load-bearing elements of a monolithic structure with a span of up to 2 m - 50%; bearing structures beams, purlins, vaults, crossbars and slabs with a span of 2 to 6 m - not less than 70%; load-bearing structures with a span of 6 m - no less than 80%; load-bearing structures, reinforced load-bearing frames, – not less than 25%.

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Determining the strength of concrete

Concrete gains its strength by 30% approximately on the 3rd day, on the 7th day the strength of concrete will be 60%, on the 14th day - approximately 80% and on the 28th day the strength of concrete is considered to be 100%. However, concrete continues to gain strength even after 28 days. On the 90th day, the strength of concrete increases by another 30-35% from 100% on the 28th day.

The ceiling must be rigid, that is, under the influence of loads, it must not deflect (allowable from 1/200 for up to 1/250 of the span for interfloor).

The optimal temperature for hardening a concrete monolithic composition is considered to be 20-25 degrees. Optimal humidity is no higher than 90%. Of course, when building a structure with your own hands, it is difficult to make appropriate measurements of the strength of concrete, but we can still focus on weather conditions and accordingly draw certain conclusions about the strength of our structure.

For example, on days when the air temperature is 10 degrees, concrete gains strength by 40-50% on the 7th day, but if the air temperature is only 5 degrees, then concrete will gain strength by 30-35%. In hot weather of 30 degrees, the strength of concrete on day 3 will be 45%. At subzero temperatures, pouring a floor with concrete mortar with your own hands is not recommended, since concrete in such conditions does not gain any strength at all.

There are special additives to concrete mortar for such cases, but we are building for ourselves and with our own hands, so it’s better to wait. For now, you can only lay beams, make wooden floors between floors, build and install a reinforced frame, but it is better to postpone pouring concrete. But if you filled beams and reinforced frames with concrete mortar with your own hands, and then the air temperature dropped below zero, then do not rush into the decision to dismantle the formwork, wait until spring and warm weather.

Thank you.

The concrete was ordered M300. Supplier - titanbeton. ru
Two drivers who visited me do not understand Russian, do not have maps, and do not know the area. The first one had to be caught in a neighboring city based on his vague tips, something like “I’m standing at a store that I don’t remember passing by.” In general, they frayed my nerves. They carry 5 m3. It would be good if there were actually 4.5 m3 there.

Separately, a few words about the concrete pump. Initial price - 18 tr. The boom is 32m, it was poured through the fence without leaving the asphalt without any problems. The driver is a good guy, although at the end he asked for 2tr more than what was supposedly stated for “moving,” but he explained and explained everything well about the filling process itself. The unit itself is very difficult to operate. Although she drove and tried to supply concrete intermittently with one “pump” of the pump, the pressure and flow speed required great effort to move the hose back and forth, directing everything inside such a narrow formwork, evenly distributing the concrete in layers of 30 cm.

A total of 17 cubic meters of concrete were ordered, the possible refusal of the last mixer at RBU was agreed in advance, payment was made on the spot. After pouring 2.5 mixers, that is, 3/4 of the total volume, after thinking and thinking, we decided to give up on the concrete unit, we were afraid that the formwork would not hold up. They began to vibrate in the old fashioned way, with reinforcement rods - for the same reason. As it turned out, not in vain.
The concrete has run out, the last mixer has left. As expected, there are 200-250 liters of concrete left in the concrete pump receiver. The driver said to point the sleeve somewhere to swing something else. Having thrown the sleeve onto the thin wall of the partition, we did not expect that in a couple of seconds he would spit out another 70-90 liters almost to the top. And then the formwork began to crack... everyone froze. On medium-height M10 studs, washers with a diameter of 30 mm were pressed 0.5-1 cm on each side into the wooden posts and, as it turned out, a nut was torn off on one of the studs. Thus, the formwork became wider by this centimeter and a half. There was no further destruction, I exhaled. Geometry violations are not critical. After removing the formwork, they are not noticeable at all.
The remaining concrete was poured onto the area next to the gate onto a sheet of film. We also dragged this concrete into the formwork in buckets, leveling it more or less everywhere, right up to the windows. Having pierced everything once again, we parted ways.

Over the next couple or three days, periodically watering the concrete, formwork was assembled on the ground closer to the foundation pit, which could accommodate a 5-cc mixer. According to calculations, a volume of 4.8-4.9 m3 was needed. Having agreed with four working crests nearby, I placed an order at TitanBeton. I made several portable ladders around the formwork, along which concrete could be poured directly from a wheelbarrow. The mixer arrived and unloaded. They started dragging. Two people constantly shovel concrete, one carries it in a wheelbarrow, two more stand inside and pass buckets to each other. I don’t remember exactly how much time passed. But the concrete did not have time to stand. In 2.5-3 hours, I think we did it. However, there wasn't even enough concrete. Everything vibrated. I drove to the market for cement, leaving myself one assistant, and made about 9 more batches of 400 liters. I covered everything with film and left.

After waiting a few days, I began to slowly take everything apart. I dismantled the trough for concrete, scaffolding, and tore off the film. The weather was rainy, so I was not afraid of the concrete drying out.