Provide for their laying with seams of 15 mm, that is, almost end-to-end. Regulatory literature prescribes the device monolithic areas with reinforcement at a distance between the plates of 300 mm.
To seal the joints between floor slabs, use concrete on fast-hardening Portland cement or Portland cement grade M400 or higher on fine aggregate... The grain size of the aggregate should not exceed one third of the inter-slab gap and three quarters of the clear size between the reinforcing rods. AT concrete mix it is necessary to introduce plasticizers and setting accelerators.
If you get a standard seam between plates 10-15 mm wide, then usually a bar of reinforcement is placed on the bottom of the seam, which is arranged in the form of a "cone", and poured with mortar.
We close non-design joints up to 300 mm
If the width of the joints between adjacent slabs does not exceed 300 mm, it is relatively easy to seal such a joint, to choose from - several ways of filling the seams.
Method 1
- From the bottom of the adjacent slabs, using spacers, we install a board or plywood sheet, bridging the gap - this is formwork;
- A piece of roofing material or film can be placed on top of the formwork, then there will be no traces of concrete on the formwork, and it can be used further;
- Fill the gap between the plates with mortar;
- We are waiting for the concrete to gain strength within 3-4 weeks, we remove the formwork.
Method 2
If it is not possible to bring the formwork from below, you can make permanent formwork made of galvanized roofing steel with a thickness of 0.8-1 mm according to the size of the gap between the plates, with support on the upper edge of the slab (trough). The profile of the side surface of the slabs will provide additional space and rigidity to the monolithic area.
Method 3
Another way to seal seams fixed formwork – from steel strips with a thickness of 4 mm and a width of 5 cm, make mounting parts along the gap profile, as in the previous case, resting on the front surface of the slabs, lay these mounting parts every 0.5 m along the length of the slab. On the bottom (in the plane of the lower edge of the slabs) we put a strip of galvanized roofing steel, plywood or plastic, and concreting. This method ensures reliable adhesion of the monolithic area to the slabs.
Method 4
If you come across a couple of defective slabs with the wrong location of the side locks, when the recess is at the bottom, they can be installed next to a gap of 2-3 cm. From below, bring the formwork according to method 1 and pour concrete through the provided gap.
Monolithic areas with a width of more than 300 mm
If the gap between the slabs is from 100 to 300 mm, we perform a monolith with reinforcement. There are also options here.
Option 1
Used when formwork from below is not possible.
- We install load-bearing beams with a section of 40x100 mm on an edge, with a step of 1 m, resting on adjacent slabs;
- We fasten the formwork panels to the supporting beams with wire twists;
- We close the formwork roofing material or film;
- Install reinforcement cage on glasses so that the reinforcement is 30 ... 50 mm higher than the formwork;
- We are concreting.
Option 2
If it is possible to fix the formwork from below, it can be used for the device supporting structure fittings.
- We build the formwork;
- We make mounting parts from reinforcement А1Ø8… 12 (depending on the width of the gap to be overlapped), taking into account that there must be a distance of at least 30 mm between the bottom of the formwork and the reinforcement;
- We put a protective material at the bottom of the formwork;
- We install mounting parts;
- We lay the reinforcement or reinforcement cage;
- We are concreting.
Do not settle for sealing the gap between the wall and the slab with lightweight concrete honeycomb blocks (foam concrete, expanded clay concrete, etc.) - they do not have the required bearing capacity. Taking into account the arrangement of furniture along the walls, this section of the floor has a large load, this will lead to the destruction of blocks and the need for costly repair of the floor.
Areas between the wall and the slab are sealed in the same way.
This story tells not only about sealing joints, but also about anchoring the plates to each other:
Ceiling seam from the underside
Inter-tile seams - the rusty walls are filled with concrete at the installation, then the ceiling is primed, putty and painted, unless another finish is provided.
Sequence of embedding of rusticates
Before concreting seams are thoroughly cleaned of dust and mortar residues metal brush , for better adhesion of the mortar to the board, the side surfaces can be primed.
- Prepared fresh concrete solution is unloaded into a container and delivered to the work site;
- With a small width of the rusticum, filling is carried out at a time, with a large width of the site - in several layers, but no more than 2 ... 3 hours;
- A small-width concreting site is bayonetted, with a large one - compacted with a vibrator;
- For the first week, the surface of the monolith is moistened with water daily;
- After 28 days, the formwork is removed.
Uneven shrinkage at home
It's unpleasant when cracks appear on the ceiling. This often happens due to:
- Uneven building settlement;
- Incorrectly selected grade of concrete;
- Poor quality concrete.
Let us dwell on the reasons for the uneven precipitation. It can occur if:
- Constructive flaws - incorrectly designed foundation;
- Foundation devices without taking into account geology, the depth of soil freezing and the depth of groundwater;
- Poorly performed work on the foundation and masonry of the walls;
- Low quality building materials.
To understand the reason for the appearance of cracks, sometimes you have to order a construction expertise.
Decorative ceilings
A protective layer of concrete with a thickness of 30-50 mm should ensure that the ceiling is free of rust stains from reinforcement, but sometimes this layer is ineffective. From contemplating stains on the ceiling, traces of leaks and cracks in rustic best remedy - installation of a suspended, hemmed or stretched ceiling.
Decorative ceiling - the best decision if necessary leveling the ceiling surface. It will close all construction flaws and complement the interior. If you want to reduce the height of the room, arrange multi-level or dropped ceilings from plasterboard, acoustic boards or combined from various materials.
Indoors low height they carry out hemmed or stretch ceilings. Here the champion - stretch ceiling, which "eats" only 3-5 cm of the height of the room.
Any problem finds its solution. Sealing seams between, even with large widths, does not pose a major structural or technical problem. From the options offered, it is easy to choose the one that suits a particular case.
The construction of a private house is a complex and laborious task, within which it is necessary to perform various types of work. For example, it may be necessary to fill in a monolithic area between floors due to the fact that it is impossible to form a floor completely from slabs according to the project. This happens very often in cases of the formation of flights of stairs or when it is necessary to lay various communication elements between the plates. It is quite possible to form a monolithic section between the slabs with your own hands. Although this work is laborious, it is quite doable if you adhere to all building codes and regulations.
In the process of forming a section of a monolith between floor slabs, it is important to correctly perform the following work:
- install props and form the formwork;
- form a reinforcing mesh;
- prepare a concrete mixture;
- pour concrete correctly.
Correct performance of these types of work will allow you to create a solid and reliable section of the monolith between the floor slabs in the required place.
Required materials and tools
Considering that the work on the construction of the concrete overlap section consists of different stages, a number of materials must be prepared for each of them. The list of such materials may vary due to different factors, including the distance between the plates to be poured. The standard list looks like this:
- plywood or boards for creating a direct surface for pouring mortar and side formwork, construction film;
- wooden beams or metal channels to create a horizontal support on which plywood or a board pallet will be laid;
- timber (120-150 mm), wooden beams or channels to create bearing supports under the formwork site;
- reinforcing bars (15-25 mm), wire for binding, metal chairs for installing reinforcing bars at the required height (you can use reinforced mesh);
- cement M400, sand, crushed stone, water for mixing concrete mortar;
- concrete mixer;
- circular for cutting beams, boards, plywood, as well as metal reinforcing bars;
- shovel, bayonet tool, trowel or a rule for leveling the surface of the overlap between the slabs, protective film to cover this area.
The amount of all materials depends directly on the distance between concrete slabs you need to overlap and what area as a whole the monolithic overlap area occupies. Usually, in private houses, such an overlap area is not very large, so its formation is not too difficult a task. However, in this case, all the same, you should adhere to a clear phasing and rules for working with building materials and designs.
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Stages of work on the formation of a monolithic section between floor slabs
Monolithic plot the overlap between the slabs is formed in approximately the same way as any. Given the small area of \u200b\u200bsuch a site, the work, of course, is simplified, but it is necessary to adhere to all building codes and regulations. Therefore, no matter what distance between concrete slabs is poured, all stages of work must be performed carefully, on which the reliability of the monolithic structure created independently will depend.
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Installation of supports and formwork
First, we form a formwork for a monolithic section, which should have such mechanical and strength characteristicsto hold a large mass of concrete solution for a long period, which will dry out for a long time.
Formwork installation is carried out as follows:
- We form the bottom of the formwork. To do this, you can first take a sheet of plywood or boards and stuff them onto beams used as load-bearing elements for the bottom. The distance between floor slabs required for pouring in a private house is usually not very large. Therefore, it is very easy to form the bottom of the formwork. Before the formation of the reinforcing lattice, it is advisable to cover the bottom with a construction film or even a simple roofing material.
- On both sides, the lateral boundaries of the monolithic section will be floor slabs. On the third, there is usually a wall. Therefore, the side part of the formwork will require the use of one simple board. Even if you need to install a side shuttering board on both sides, this will also not be difficult.
- Under the beams or boards, used as the main holding elements of the bottom, we supply vertical supports and fix them in such a way as to completely eliminate the possibility of the bottom of the formwork sliding off the load-bearing vertical supports... Often they even use a univil for this. However, in the conditions of private construction, without special supporting equipment, it is possible to fix individual parts of the formwork structure with each other using nails, staples, etc.
- It is imperative that the foundations of the formwork bearing supports are firmly supported in the floor plane. For this, you may need to compact the soil, put some kind of tiled or board material, etc. It all depends on what kind of floor is at the construction site at the time of creating a section of a monolithic floor.
Having created a reliable formwork and making sure of its strength, you can proceed to the next stage of work.
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Reinforcement mesh formation
No matter how small the monolithic area created between the floor slabs is, it must be reinforced. If the distance between the floor slabs is more than 1.5 meters, then it is advisable to use a reinforced mesh in addition to reinforcing rods. With a small gap, it will be enough to install two layers of a lattice of rods.
Reinforcement grid is formed quite simply:
- We saw off the rods of the required length based on the formation of a reinforcing lattice with a step of 15-20 cm. We connect the rods with each other using a wire. We form two layers of such a reinforcing lattice.
- Using reinforcement mesh We put the first layer of the lattice on special metal "glasses" that raise the lattice by 5 cm from the bottom of the formwork. Then we lay the mesh and put another layer of reinforcing lattice on top of it.
- A small area between the floor slabs can be reinforced with conventional frame from rods - without a grid. It is necessary to form the frame in two layers, so that each of them is 5 cm away from the edge of the floor slab. All work can be carried out without a welding machine. simply by tying the rods with ordinary metal wire.
Sometimes you can come across a recommendation that the reinforcing bars should be inserted into the holes pre-drilled in the floor slabs. This should not be done. The created monolithic section will be supported by mounting recesses, which necessarily exist along the side planes of any floor slab models. Such mounting recesses are longitudinal, round (in the form of a glass). They are enough to provide reliable support for the monolithic concrete area between the slabs.
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Concrete mix and its pouring
When you start mixing a concrete solution, you need to make sure that there is a sufficient amount of materials necessary for it. Having calculated how much volume is required to be poured, it is necessary to calculate how much cement, sand, gravel and water will be required to prepare the solution. This is done using a simple formula. For a medium-sized monolithic site, concrete grade 200 is suitable. For private construction, it will be enough to use cement M400 for mixing this grade of concrete. The calculation for 1 m³ of such a solution is made from the following indicators of the mass of all materials:
- 280 kg of cement M400;
- 740 kg of sand (approximately - 0.55 m³);
- 1250 kg of crushed stone;
- 180 liters of water.
It is very simple to calculate how many meters of cubic solution you need in total, because a monolithic section is usually a rectangular parallelepiped. And having prepared everything necessary materials, you can start mixing the solution in a concrete mixer.
When working with a concrete mixer, you should follow a few simple rules:
- do not exceed the rated load of the concrete mixer;
- install the concrete mixer exclusively on a flat surface;
- unload the finished solution first into a separate container, and then transfer it evenly to the required place.
The last rule is not relevant if the solution is fed directly from the concrete mixer into the formwork prepared by us under the section of the inter-tile monolith. In addition, it is very important that between separate stages pouring the solution took no more than 2-3 hours. If the area is not wide, it is best to do everything in one fill. After pouring the solution into the formwork, it is necessary to level the surface of the filled area with a rule or a trowel. It is very convenient to use for this a flat board with an emphasis on the floor slabs between which the monolithic area is poured.
Even in professional floor layouts, a monolithic section between slabs in buildings is often found complex configuration... Concreting this piece is much easier than casting a solid slab, since the lower, upper level is set by default, there is no side formwork, the lower shield is enough. One option is to use precast-monolithic floor SMP.
Monolithic slab technology
AT individual construction more commonly used slabs standard height 220 mm. This must be taken into account when reinforcing homemade plotensuring the minimum possible protective layer 15 - 30 mm. If the monolithic area between the floors will protrude above the adjacent ones, an increase in the thickness of the screed will be required when finishing the floors.
Factory floors have voids in which it is convenient to stretch the electrical cable. In a homemade slab, communications must be bricked up before pouring so as not to hammer the concrete later. This technique often used for the manufacture of hatches. If openings for stairs are cut in industrially manufactured slabs, the reinforcement scheme is violated, the structure loses bearing capacity, becomes dangerous for operation.
Formwork
The monolithic section between the slabs is poured onto the shield, which must be supported from below with racks. The simplest calculations of sawn timber cross-sections are the most a budget option for an individual developer, show that boards, timber with minimum dimensions can be used for formwork:
In this case, the structure will support the weight concrete floor without sagging, changing geometry.
By default, the monolithic section between the floors has a side formwork, which are the ends of reinforced concrete products laid in place. It remains to place under the bottom surface of the board, bringing their edges under the existing PC plates, to check the flatness, the absence of bending in any direction. To do this, you need to follow the steps:
After that, between the extreme pillars, the remaining pillars are mounted, ensuring the horizontalness of the beams, girders, deck boards. When choosing wood of grade 2, the bending strength of the lumber is insufficient. Besides bottom strapping pillars with boards of 25 mm, necessary to prevent shear during pouring, a similar strapping is additionally used at the level of 1.3 - 1.5 m. All pillars are sewn "inch" across, lengthwise, forming a rigid spatial structure.
Stackable racks are used to facilitate demoulding:
- they are made less than the design height
- build up in pieces in the upper part, which is enough to unscrew during dismantling
When stripping the form, first dismantle the lower bars of the racks, then remove the beams with the upper pieces of the racks. After that, the deck is dismantled with the girders screwed to it. In the future, all lumber is suitable for construction rafter system... If you choose grade I wood, you can reduce the cost of the "inch" board for strapping the posts in the middle part.
If it is necessary to fix formwork elements to existing walls, it is better to use anchors with metal sleeves. They are easily removed from the masonry after stripping, unlike the dowel-nails, the plastic elements of which are almost impossible to remove from the wall.
Deck
At this stage, the monolithic section between the slabs is equipped with a deck on top of the purlins. The edges of the boards are brought under the existing floor slabs, the middle lies on the beams, which ensures the rigidity of the structure.
The gaps between the boards are foamed from the inside of the formwork (from above), the boards are covered plastic wrap... This will keep water in the concrete, facilitate demoulding, and prevent the floor slab from cracking. Plank construction is convenient for wiring engineering systems - holes of any diameter are drilled with crowns, drills without problems in any area.
When the width of the hollow section is less than 1 m, the technology is often used without posts, beams:
The deck is attracted by wire twists through the timber to the lower planes of the laid slabs, reinforced, poured according to standard technology. It is not recommended to punch holes for reinforcement at the ends of the slabs, since they weaken the structure of hollow PC products. Wire clamps cut off angle grinders when stripping flush, part remains inside a monolithic piece.
To increase the overlap resource, reinforcement of at least A-III periodic section (hot-rolled) with a diameter of 10 - 16 mm is used. The main nuances of reinforcement are:
For knitting the joints of the cells, a wire of 1 - 2 mm is used, the knots are created by manual, mechanical hooks, homemade equipment installed in a screwdriver or with a special knitting gun.
The area between the slabs can be reinforced with a ready-made mesh or a mesh connected on site. In the first case, the dimensions of the longitudinal, transverse rods are removed, taking into account 4 cm of the protective layer on each side. The nets are knitted on flat areas, laid on the deck on top of the film on spacers 15 - 30 mm. More often used concrete blocks 10 x 10 cm or plastic coasters with cross-slotted fittings.
For the top layer, these devices are not suitable due to small size... Clamps, staples, tables are used here different forms, designs. The main task of these elements is to support the upper mesh in the design position (15 - 30 mm below the slab plane).
For bending reinforcement, apply homemade gadgets... For example, a 50 - 70 cm piece of pipe with a 10 - 15 cm mandrel welded to one of its edges will provide the required radius (5 bar diameters) and reduce the force.
The area between the slabs may contain nodes for the input of engineering systems. Embedded, void formers are installed after or before reinforcement, depending on the location, configuration, size. For example, it is better to mount an 11 cm sewer cross before laying the nets, sleeves for water pipes can be installed at any stage. 
Void formers of complex shape are required for specific communications. Therefore, they are usually made from polystyrene foam, expanded polystyrene, cutting into pieces of the same format to achieve the desired length from a 5 cm sheet.
For rigid fixation, absence of movement of light polymer fittings, expanded polystyrene holders when pouring the floor, the following technology is used:
- plugs are put on the fitting
- fixed with self-tapping screws from below through the deck
- or the plug is screwed on from above
- then a fitting is put on it
These areas, poured on their own, can be supported by internal flights of stairs... For them you need:
- release bottom mesh reinforcement
- to make a step for supporting the reinforced concrete structure of the march with a reciprocal seat
- install the formwork for the staircase / hatch
To release the reinforcement, you will need to make cuts in wooden board lintels chain saw... Put the board on the reinforcement, passing it through the cuts, foam the remaining slots. Steps, recesses are created by screwing narrow strips to the formwork from the inside.
Fill
Before placing concrete between floor slabs, it is recommended to prime the ends existing slabs to improve adhesion. Basic guidelines for concrete works are:
Solar ultraviolet light, hot dry weather, frost are contraindicated for concrete. Covering with burlap, sawdust, sand allows the surface to be wetted without destruction. The film protects from the sun's rays in summer, in winter it provides the principle of a thermos, keeping the heat that forms during the hydration of cement with water.
The concrete grade is selected in accordance with the standards of SP 63.13330 for reinforced concrete structures:
- density - 1 800 - 2 500 kg / m 3
- compressive strength - from B7.5
Water tightness, frost resistance for structures operated indoors does not matter much. When self-production concrete, it is necessary to take into account that the probability of cracking is sharply reduced if a filler of various fractions with a continuous row of grains is used. The sand should not exceed 1/3 of the total volume of the aggregate.
After pouring between the floor slabs, sagging may remain in the newly made section. They are polished with a diamond tool for angle grinders (grinder) of the disc type. If the project includes a self-leveling, warm floor, screed, alignment of the joints is not necessary. For better adhesion of two adjacent reinforced concrete structures, grooves can be made in the lateral edges of the factory plates if the appropriate tool is available.
When placing concrete, these recesses are filled with a mixture, two slabs are obtained almost monolithic. The quality of the lower edge of the slab is usually inferior to factory counterparts, therefore, finishing with stretch, level ceilings is often used. 
This technology is very convenient in the manufacture of hatches or stairways. These technological holes can be reinforced with rods diagonally located near them, dramatically increasing the strength of reinforced concrete. Cutting a hatch into a factory slab compromises the integrity of the mesh reinforcement, weakening the default design. This is especially true when the opening is shifted to the middle of the slab.
The technology of a self-made monolithic overlap section allows you to fill the voids when laying out the slabs without reducing the structural strength. Even without pre-tensioning of the reinforcement, the slabs have a high resource if the specified requirements are met.
Comments:
Building a house is a very laborious task that includes quite a lot of work. For example, pouring a monolithic section between floor slabs is also among them, since construction from only slabs is not possible. This problem, as a rule, arises in cases where it is required to lay communication elements or form a flight of stairs. It is worth noting that, adhering to certain construction rules, you can carry out this process yourself.
When creating monolithic overlap sections, it is necessary to correctly install the support, form the formwork, reinforcing mesh, make a mixture of concrete and pour it.
With the correct execution of all the above works, the monolith section between the floor slabs will be as strong and reliable as possible.
Materials and tools required for work
For each stage of work, you must prepare your own set of materials and tools. Their list may differ only due to some factors, for example, the distance between the plates that you want to fill. However, there is still a standard list that includes the following materials:
The area between the floor slabs is filled with concrete, pre-reinforced.
- boards that will be used to create side formwork and surfaces;
- wood beams or metal channels, which will serve as a support for plywood or a board pallet;
- timber for creating bearing supports for the formwork platform;
- reinforcement rods, wire with which the bundle will be made, metal chairs;
- concrete solution, which is made from sand, cement M400, crushed stone and water;
- concrete mixer;
- circular saw, shovel, trowel, bayonet tool and protective film.
As for the amount of material, it depends on what kind of overlap area needs to be done, as well as on the overlap area itself. If we talk about a private house, then in such buildings it is, as a rule, not very large, so it will not be difficult to cope with the work on your own.
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Stages of forming a monolithic overlap area
Forming the area between the slabs is no different from creating any other. Despite the fact that the work area is relatively small, adhere to building regulations is still worth it, so all stages of the work must be performed carefully. It depends on this how reliable the monolithic structure will be.
The first thing that needs to be done is to form a formwork for a monolithic area. In this case, it is necessary to take into account the fact that the concrete solution weighs quite a lot, moreover, it dries for a long time, therefore the strength and mechanical characteristics of the formwork should be such as to keep it for a rather long period of time.
How the formwork is installed:
Formwork for a monolithic area between the slabs
- The bottom is made, for which a sheet of plywood is taken, and beams are stuffed onto it, which will play the role load-bearing elements... Since the distance between the slabs in a private house is not so great, it is not difficult to make the bottom of the formwork. Before shaping reinforcing grid, we cover the bottom with roofing material or construction film.
- The boundaries of the monolithic section on the sides will be floor slabs. There is usually a wall on the third side.
- Vertical supports are brought under the holding elements of the bottom, which are the beams. They must be fixed so that the bottom of the formwork does not slide off the vertical supports, which are load-bearing. For this, a unilk is used, although not always. As a rule, during the construction of a private house, there is no special supporting equipment, therefore, the fixing of parts of the formwork can be done with nails or staples.
- An important point in this process is the support of the formwork in the floor plane, which should be as strong as possible. This can be achieved by compacting the soil and backing up with some kind of board or tile material.
After the formwork is ready, and there is no doubt about its strength, we proceed to the next stage.
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Making a reinforcing grid
Regardless of the size of the site, it must be reinforced between the floor slabs.
If the distance between the slabs is from 1.5 m, it is best to use a reinforced mesh in addition to the reinforcing bars. If the distance is small, you can limit yourself to two layers of a lattice of rods.
Reinforcement mesh formation process:
The reinforcement grid is laid 5 cm above the bottom of the formwork, the reinforcement is pulled together with wire.
- The rods must be sawn off of a certain length, taking into account the step, which should be about 15-20 cm. Further, the prepared rods are tied together with a wire. As a result, you should get two layers of lattice.
- When installing the first layer, the reinforcement grating must be laid 5 cm above the bottom of the formwork, for which the "glasses" are intended. After that, laying a grid on top, lay the second layer of the lattice.
- If the area between the floor slabs is not so large, the reinforcement can be made with rods without mesh. The frame in this case is formed in two layers, and each of them must be 5 cm away from the edge of the slab.It is worth noting that to use welding machine this process is optional since all connections can be made with metal wire.
Some people advise inserting reinforcing bars into holes pre-drilled in the slabs, but this is not worth doing. The monolith section will be supported by the recesses that are present on any floor slab models. They can be either longitudinal or round, resembling a glass.
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Making and pouring concrete
Table of proportions of components for the manufacture of concrete.
Before you start mixing the concrete solution, you need to prepare all the necessary components. Since the monolithic area looks like a rectangular parallelepiped, then calculate required amount solution in cubic meters it won't be that hard.
After all the components are prepared, you can proceed to making the solution in a concrete mixer, observing certain rules:
- adhere to the loading rate;
- the concrete mixer must be installed on a perfectly horizontal surface;
- the solution must be unloaded into a special container, and after that - to the required place.
Concerning last rule, then it can be broken only if the concrete mixer is installed next to the formwork, and the prepared solution is discharged directly into it. Refilling should be carried out no later than 2-3 hours later. You can make one fill, this is important if the area is not wide. After that, the surface must be leveled, for which a trowel or rule is used.