Comments:

During the construction of the building, such an important question should be taken into account such as the opacity of the ceiling slabs.

Construction standards on this issue have special instructions.

An important structural element

Overlapping is the bearing elements of the building made of reinforced concrete structures. They get and distribute loads from their weight and in the building of people and equipment on the walls and supports. With their help, the internal space of the structure is divided into floors, and also separates the attic and basement.

Overlapping in the building must respond to many requirements. They must be durable, rigid, have good sound insulation characteristics, do not burn and do not pass water.

Material used for the production of floor slabs - reinforced concrete. These are mainly multi-standard structures with voids of different forms: polygonal, oval, round. Most often in construction uses elements with round voids. They are high strength, technological and fully prepared for installation. The bearing capacity of them is 800 kg / m². They are placed on the bearing walls located at a distance of about 9 m from each other. Rely on two sides. They are distinguished by fire resistance, rigidity, long life. As a material for walls, such overlapping elements will be placed, brick, aerated concrete, foam blocks and reinforced concrete panels are used.

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Some calculations

To find the size of the opening plate of the overlap, the basis for which it is planned to be laid is planned. It is mandatory to take into account the length and weight of the design, the thickness of the wall-support, the seismological stability of the building. In addition, it must be taken into account the load and its character, it will be temporary or constant. Such calculations should be carried out by specialists. For an individual developer when drawing up a project and installation, the main reference is the labeling of the manufacturer.

When using flat overlapping elements, the span value can be calculated as follows: you need to summarize the thickness of this element and the distance between the two supports. As for the depth of the recycling of the slab overlap on the basis of the brick, this value should be equal to the thickness of the structure itself, but be at least 70 mm. To calculate the minimum thickness of the outer wall, which will be the basis for plates of the overlap, it is necessary to take into account the thermal insulation layer and facing material on the end parts of the latter. Thus, the construction of a thickness of 140 mm should maintain the base whose thickness is at least 300 mm.

Installation of specialized design structures, which have liners, involves the minimum deepening of the slabs of the overlap base - 150 mm. When installing, you should not allow you to enter the wall of hollow liners. If the ribs are reinforced with two rods, then it is necessary to start them in one on the support. If the edge has one rod, then the clamps will take a tangent stress.

Armofamed designs are analogs of flat. Therefore, the minimum value of the depth of the content of these elements can be determined in the same way. The thickness they must have no less than 90 mm, the support occurs on two sides.

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Individual Construction

In specialized literature on construction work, it is determined by the necessary norms regarding the depth of the opening of the slabs of the overlap. This indicator is within 90-120 mm. For a more accurate definition of this value, certain calculations should be made, in which the length and weight of the structure, the thickness of the wall-support and the material from which it is made are taken. Also, the estimated load should also be defined.

For example, the use of the plate, the length of which is 6 m, suggests the depth of the support to the base of the brick of at least 100 mm. When using structures from reinforced concrete or steel, the depth of at least 70-75 mm is allowed, on the walls of foam blocks and aerated concrete - at least 120 mm.

Currently, three ways to build overlaps in the house are most popular in our country. This is the installation of ceiling slabs, a monolithic reinforced concrete overlap device and a flooring device on wooden (less often metallic) beams. All these methods and not only we will definitely speak. And the first technology that we will look at is the installation of finished slabs of overlapping.

To start a little about the slabs themselves. Depending on your form, all the plates can be divided into flat and ribbed. Flat in turn are divided into solid and void. We are now interested in void, because It is this type of slab and is used mainly in low-rise construction.

Honeycomb stoves are also classified according to various parameters, such as the shape and size of emptiness, plate thickness, plate manufacturing technology, reinforcement method.

I will not delve into the subject of classification. This information is better to search on the sites of manufacturers of concrete products (reinforced concrete products). We will be better talking directly about the installation.

The very first moment on which it is necessary to pay attention to the design of its future home is the ability to purchase plates of those sizes in your area, which are laid in the project. Each manufacturer has its own defined nomenclature of products and it is always limited. This is really important and I am surprised by the fact that very often developers forget about this recommendation and then they have to either chop one or more plates, or to do a monolithic plot at the overlap. We will talk about it below.

Warehousing slabs of overlapping at the construction site.

Of course, it's great if you have the opportunity to lay overlap plates immediately when you deliver directly from the car that brought them. But most often this does not happen. Or the driver insists that you discharge the plates as quickly as possible, because It is in a hurry to the next order, or the plates are laid on the car not in the order in which you need, or you just bought them in advance and put it is not going to lay. In all these cases, the slabs will need to be stored on your site.

Try to choose for this smooth surface. Never put the plates right on the ground. Must under the edges of the plate need to put something, for example, trimming a wooden bar. The lining should be only two, at a distance from the edge of approximately 25-40 cm. Under the middle of the plated lining can not be installed.

Plates can be stored with a stack of up to 2.5 meters high. The lining under the first slab makes higher so that if they are given to the ground when laying the subsequent plates, the first one did not touch the Earth, otherwise it can easily break. All subsequent lining is enough to do even out of an inch (2.5 cm). It is necessary to place them in the stacker above each other.

Preparation for mounting slabs.

Preparation begins at the moment when bricklayers drive out the last rows of masonry. The plates will lie down smoothly and without drops, if the upper rows of bearing walls will be smooth and will be in one horizontal plane.

To achieve this, it is necessary to have a horizontal level mark in all angles of the room. They put them in the process of erection of walls with a level or a laser level, or a hydraulic level. And when the last row of masonry is done, the roulette is controlled by the distance from the marks to the top of the walls. In all corners, it should be equally. From my experience I can tell you exactly that some bricklayers neglected by this, especially when they make a stuffing masonry simultaneously with the front, performed "under the rod".

The top row of bearing walls should be a tychkoe. That is, if you look from the inside of the closed room, then on the bearing walls (on which the slabs of the overlapping are based on) in the very top row of the masonry should only be visible.

If the plates are put on the carrier partition with a thickness of 1.5 bricks (i.e., the plates are based on both sides), then the upper number of such a partition is laid out by one of two ways:

Before laying plates of overlapping onto walls from various blocks (foam concrete, gas-silicate, slag, etc.), it is necessary to make a reinforced concrete belt (usually about 15-20 cm thick). Such a belt is made or pouring concrete into a formwork, or using special U-shaped blocks around the entire perimeter of the house box, i.e. Not only on the bearing walls, but also by non-carrier.

When installing hollow slabs, the overlap of the hole in them must be embedded. It is much more convenient to do in advance until the plates are lying on the ground. In general, the SNIP prescribes to close the voids necessarily on the side of the plate, which relies on the outer wall (to reduce the probability of the plate freezing), and from the side that relies on the inner partition, only starting from the third overlap from the top of the house and below (to increase strength). Those, if, let's say, there is a base overlapping in the house, the overlap between the 1st and 2nd floor and the attic overlap over the 2nd floor, then it is necessary to close the emptiness from the carrier partitions only in the base overlap.

I will say that we can always close the holes when laying the holes. Moreover, recently increasingly round-standing plates come from plants with already sealed holes. It's comfortable. If the holes are not embedded, we insert the one-and-a-half brick in them (you can even half) and the remaining slots are poured with a solution.

Also before installing the plates, it is necessary to prepare a platform for the crane in advance. Well, if in place where the crane of the ground will stand, as the native, lying. Worse, when the ground is mighty. If you have a basement, you can not put a crane too close to the house, in order to avoid what is shown in the figure below:

In such cases, it is better to order a truck crane with a longer boom. Also, sometimes in place where the crane will stand, you have to first lay several road plates (usually there are somewhere used). Often it has to do in the fall in rainy and slurted weather, when the plot for so much "smashes" that the crane will simply dangle on it.

Laying plates of overlapping.

For mounting the slabs of the overlap is quite three people. One clins the plates, two laid. If you wish, you can cope and together, although not always. It happens that when overlapping, for example, the second floor installers and the craneer do not see each other. Then at the top, in addition to 2 people, directly laying the slab, there must be another person who will serve a crane team.

The laying starts from the wall on the layer of the solution not more than 2 cm. The solution must be sufficiently thick so that the plate does not squeeze it completely from the seam. After the craneman puts the plate on the walls, it first leaves the slings stretched. At the same time, with scrap, the slab, if necessary, is not difficult to move a little. If the upper surfaces of the bearing walls were made smooth, then the plates will go to bed smoothly, without drops, as they say "from the first approach."

Regarding the size of the plates on the walls, I will give an extract from the document "Manual for the design of residential buildings. Vol. 3 (to SNiP 2.08.01-85) 6. Overlap ":

Paragraph 6.16.: The depth of the prefabricated plates on the walls, depending on the nature of their support, it is recommended to take at least mm: when describing the contour, as well as two long and one short sides - 40; when working on two sides and span plates of 4.2 m and less, as well as on two short and one long sides - 50; When painting on two sides and spit plates more than 4.2 m - 70.

When prescribing the depth of the recycling, the slabs of the floors should also take into account the requirements of SNiP 2.03.01-84 to the anchoring of the reinforcement on the supports.

We try in our practice to make a resting at least 12 cm, the benefit now there is an opportunity to acquire exactly those plates that need. The step of their length is 10 cm.

Often I hear the disputes about whether it is possible to describe the wetting plates of overlapping on the three sides (two short and one long) and how much can start the plate with a long side on the wall. From what is written above, it follows that the plates can be described. But it is not so. If you read the specified SNiP, then it says that the plates that rely on the three sides have a different reinforcement scheme, rather than those that relieve only two sides.

The overwhelming majority of hollow plates, which are now produced by the Zbi plants, are calculated on the resting on two short sides, so it is not recommended to start them with a long side on the wall. With a certain load, it can lead to cracking plate. The reinforcement scheme and therefore the possibility of supporting the slab on the third direction you need to specify the manufacturer.

Also an error associated with the wrong loading of the plate is overlapping two spills at once (see fig. Below):

Under certain adverse conditions, the slab can be cracked, and the place of the crack is absolutely not predictable. If you still use this scheme, make a grinding incision (to the depth of the disk) on the top surface of the plate strictly over the middle partition. Thus, in the case of which the crack will pass precisely on this incision, which is not scary in principle.

Of course, it's good if we manage to overlap exclusively entire plates. But circumstances are different and still sometimes some kind of slab (or not even one) have to chop along or across. To do this, you will need a Bulgarian with a diamond disk on concrete, a sledgehammer, scrap and not the most slandered man.

To facilitate work, the slab is better put on the lining. Moreover, this lining is placed under the cut line. At a certain point, the stove will simply break through this line from its own weight.

First of all, we make a breakdown on the top surface of the slab with a grinder along the cutting line. Then, causing a sledge hammer from above, cut down the strip on the top of the plate. Punch concrete in the field of emptiness is quite simple. Next, we break the lower part of the plate (also by voids). When cutting the plates along (rubies always on the hole in the stove), it breaks pretty quickly. With the hatch, if the slab after the destruction of the bottom part is not broken, the sledge hammer strikes from the side of the vertical partitions of the slab to the victorious.

In the process of cutting the fitting fittings cut. It is possible with a grinder, but more securely welding or a gas cutter, especially when the reinforcement is pre-tense plane. The disc from the Bulgarian can eat. So that this does not happen, do not cut the reinforcement to the end, leave a couple of millimeters and after breaking it with the blow of the same sledgehammer.

Several times in your practice we had to chop the plates along. But we never used to say so "hardware" with a width of less than 60 cm (there are less than 3 holes), and I do not advise you. In general, taking the decision to cut the plate, all responsibility for the possible consequences you completely take on yourself, because no manufacturer will tell you that you can cut the plate.

Let's now see what can be done if you still lack a whole number of plates to completely cover the room:

Method 1 - The first or the last (maybe both) plates put it, without bringing the long side to the wall. The remaining gap is laying brick or blocks, having no more than half of the wall (see Fig.):

Method 2. - We do the so-called "monolithic section." A formwork from plywood is placed on the bottom, the reinforcement frame is made (see Fig. Below) and the plot between the plates is poured with concrete.

Anchoring overlap slabs.

After all the plates are laid, their anchors are produced. In general, if the construction of the house is carried out by the project, then the anchoring scheme should be present in it. When there is no utter, we usually use the scheme shown in Figure:

Anchor is done with the end of the end in a loop that clings to the mounting loop of the plate. Before welding the anchor to each other and to the mounting hinges, they need to be pulled as far as possible.

After performing anchoring, we immediately close the solution all the mounting eyes in the stoves and the rusts (seams between the stoves). Try not to delay with this so that the rustle does not get a construction trash, and the water was not flooded with rain and snow. If you suspect that the water in the stove still hit (for example, we bought the plates with already sealed emptiness, and rain water could even get when stored at the factory), it is better to release it. To do this, after laying, simply drump up the perforator one by one small hole in the plates from the bottom, in those voids where the mounting eyes are located.

Especially dangerous is the foundation of water in voids in the winter when the house still does not heal (or not at all completed) and the plates are frozen below zero. Water satuates the bottom layer of concrete, and with a repeated cycle of freezing-defrosting the plate just begins to collapse.

Another way to fasten the plates is the construction of the so-called concrete ring anchor. This is a kind of monolithic reinforced belt, only it is not done under the plates, but in the same plane with them, also throughout the perimeter of the house. More often such a method is used on, foam concrete and other blocks.

Immediately make a reservation that we never used it because of much greater time consideration. I think the annular anchor is justified in more seismic regions than our Nizhny Novgorod region.

At the end of the article, I propose to see a small video in which we are talking about choosing the slabs of the overlap:

There is a lot for this article - a lot of mistakes allow the builders.

What is a collection plate (empty or ribrant)? This is primarily reinforced concrete design designed for a certain job. Any reinforced concrete can only work with such a scheme when the voltages in it can pick up the working fittings.

In prefabricated plates, the working fittings is located only in the lower zone of the plate and only along the plate. What does it mean? This means that the slab without destruction can be bent only in the longitudinal direction and only so that the bending of the plate is directed down.

As can be seen from the figure when the stove bends, its lower part is stretched, and the reinforcement takes the stretching voltage at the same time, because Concrete is not capable of it. Concrete without reinforcement with bending will only crack and collapse. With the slightest bend, we need to install the fittings that will take the stretching tension of the bend on themselves.

Now back to the collection plates. We know that the working fittings of the plate is located only along the plate and only at its bottom face.

Consider below various situations of the overlapping slabs.

How can I desire prefabricated slabs

1) Classic method of supporting the stove: on two sides.

Everything is sustained here in the best traditions: the plate is bent under the weight of the load, the working fittings picks up the bend voltage, and if the load does not exceed the carrier plate, no destruction occurs - everything works according to plan.

2) Opportuning plates in three sides (two short and one long).

This method of support is also called with a stove with a stove on the wall. It is allowed to be applied when the width of the span plate is not placed, and the monolithic portion is impractical. Compared to the previous option, this option is worse than the slab, but in principle, it is not prohibited. The main thing is to remember: it is desirable a slab on the long side does not start deeper into the wall than to the height of the plate (with a plane height of a 220 mm plate, do not be deeper than 220 mm) so that pinching is not formed. What is pinching, and what it is harmful to prefabricated plates, will be considered in the article a little further.

In this case, not the entire stove bended, but only the free edge. But still at the same time, longitudinal working fittings come into operation and picked up tensile stresses - just not in the entire stove, but in its parts.

How can not be prefigured prefabricated slabs

As we remember, the working fittings in the stove is only in the longitudinal direction. In the transverse direction there is only a minor mesh that can perceive the load from the safety slab on the installation period (when the loop rises with a crane for four loops). And if we are an inmost plate on two long sides, under load it will begin to bend as in the figure, and it simply will not be sufficient fit of the reinforcement in this direction - the stove will start cracking. At the initial stage, the existing grid will be able to perceive the existing grid, but (I repeat), the area of \u200b\u200bthe reinforcement of this grid is calculated only on its own weight of the slab.

2) Additional support device in the stove span.

It is necessary to remember once and for all: the prefabricated plates work exclusively as one-time. If somewhere in the span a wall or column appears, it is shown in the figure above. The stove between the supports bends down, and above the support occurs in the opposite direction - with a stretched zone at the top. But in the upper zone of the plate we have no workforce, and we have nothing to perceive the tensile tensions of bending. As a result, cracks appear in the upper zone of the slab, as shown in the figure. It can only be one crack, but it will be enough to lead to emergency to emergency.

3) Opportuning the collection plate for two walls with the removal of the plate of the slab in the form of a balcony (console).

This situation is approximately the same as in the previous case. There is no top fittings, there is nothing to perceive the stretch. The larger the length of the console and the larger the load on it (especially on the edge), the faster there will be destruction.

Svet plate in another direction will be the same emergency as shown in the figure.

4) Opportuning the cooker plate on columns (point supports).

If you want to open the plate not on the walls or beams, but straight to the columns, remember: it is impossible to do this. The principle of operation of reinforcement in reinforced concrete: the stretched fittings in the stove works only when its ends are headed on the support. If under the edge of the plate (and under the end of the reinforcement rod), there are no supports, such an armature turns into a useless ballast.

In the picture, we see the option of supporting the plates on 4 columns. First, the stove begins not only in the longitudinal, but also in the transverse direction - and how we found out from paragraph 1, in this case cracks may form. But this is not the worst thing - these cracks simply will not have time to form due to an emergency in another direction. So, secondly, we have only two extreme reinforcements on the support, the rest "hung in the air" and do not turn into work. This means that the area of \u200b\u200bworking reinforcement in the stove decreased many times in comparison with the required. Naturally, such a stove will strive to collapse.

The best way out of this situation will be the device beams in the right place of supporting the stove - between closely located columns.

5) pinching the collection plate of the overlap.

What is pinching? In the case of supporting the slabs of the overlap is the installation of the plate on the wall more than the magnitude of the height of the slab section and the suspension of the wall. The fact is that the pinched plates work at all as hingedly relying. All prefabricated plates are designed for hinged support (when the stove is missing, as if rotates on the support). In regulatory documents on the collection plates, the depth of the support is clearly stipulated, and it should not be not only less than the specified one - it can not be done too large.

Consider in the figure, which brings the plates to the support.

With a hinge support, the stove simply rotates a bit on the support and stretched in the lower zone - there is a lower work fittings.

When pinning the plate too deeply, it is started to check, as a result, it is bent in a cunning way when the lower zone of the plate is stretched in the center, and the support is the top. And in this upper zone, we do not have enough fittings to perceive stretching efforts. As a result, cracks are formed, which are especially dangerous to what they are not visible (they are hidden under the floor), but over time they expand and lead to emergency state.

I hope this article clearly demonstrated how you can design the prefabricated (empty, ribbed and full-scale) plates, and it is impossible.

class \u003d "Eliadunit"\u003e

Comments

1 2 3 4

0 # 91 Irina 12/14/2019 10:03

Quote Ksenia:

0 # 92 Taras 06.02.2020 10:21

Quote Irina:

Quote Ksenia:

Hello! In our private house there was a situation of which blood is fastened and this is not an exaggeration. When building the first floor, 27 years ago, two slabs of overlappings were laid with a rough impairment, they lay on the wall only 5 cm on each side. Plates 4.20 long. Now these plates, especially alone, shift the wall to which they rest. In short, after some time everything collapses. I do not see any more exit, except inside the room to build additional walls around the perimeter of the room. If you have time ..... there is no money from the word at all. If you take off the floor, make the foundation and lay out the walls in the brick, so that the stove create support will correct this situation? Full of the house of children, there is nowhere to go, everyone will have to do without departure from the house. Answer please.

Ksenia, write me on the postyandex.ru

I will advise you. Is free

0 # 94 Irin 06.02.2020 11:51

Quote Oleg:

Irina, since you are considering including the options of gross mistakes, then I think this article will fit well in addition that it is impossible under the stove in the zone of support to lay the reinforcement bar (and even more so lay in the project!). Some builders even with considerable experience allow this error and require young designers of the corresponding support node. I met that. Builders are made allegedly for compliance with the thickness of the solution under the stove. If the project is laid under a stove of 10 mm, then they, pests, lay the rod with a diameter of 10 mm.
Why not? One of the main prescriptions of the solution under the stove is a uniform distribution of the load, and the reinforcement bar is a voltage concentrator. Those. The load will be transmitted through such a metal wedge. Brick under this rod can crack / bell, because The solution will fill either in a row with a rod, or an excess solution is extinced during alignment, and the stove will begin to rely on this metal wedge.

Ksenia, write me on the postyandex.ru

I will advise you. Is free

Good day, please describe how to solve the problem, which Ksenia wrote about.
The question is important for many. Thanks in advance

In case of emergency, it is primarily a thorough examination with the clarification of all factors. Without this, any instructions may lead to a deterioration in the situation.

Reinforced concrete plates are one of the most common types of overlaps. They provide high strength and allow you to mount a rigid construction as soon as possible. Mounting slabs of overlapping is a responsible task that requires certain knowledge in the field of construction. About everything in order.

Types of floor slabs

Before starting to mount a horizontal design, you must select the type. Reinforced concrete precast designs are available in the form:

• multi-profile;
• flat (PT);
• tent panels with ribs located around the perimeter;
• with longitudinal ribs.

Most often choose the use of reinforced concrete crowded. They are produced two species, depending on the method of manufacture:

• round-standing (PC);
• continuous molding (PB).

Scheme of a multi-profile slab overlap with holes

Row-standing plates - proven time products that have been used in construction for several decades. There are many regulatory documents and installation rules. Thickness - 220 mm. Products are installed according to serial sizes, which creates inconvenience in individual construction.

The manufacturing technology of these plates implies the use of reusable forms to fill, and before the manufacture of non-type products, first will be prepared to prepare a formwork. Therefore, the cost of the desired size can increase significantly.. Typical PC plates have a length of 2.7 to 9 meters in 0.3 m increments.

Concrete products diagram with dimensions

The width of the reinforced concrete products can be:

• 1.0 m;
• 1.2 m;
• 1.5 m;
• 1.8 m.

The designs of 1.8 m wide are extremely rare, because due to the high weight, the installation process in the project position is greatly complicated.

PB are used almost the same as the previous type. But the technology of their manufacture allows you to give the product any length. Thickness - 220 mm. Width like a PC series. The disadvantage is a little experience in the use and rawness of regulatory documentation.

Flat PTs often acquire in crowded elements to multi-duct plates. They are produced with a thickness of 80 or 120 mm and have smaller sizes that allow you to overlap narrow corridors, storage rooms, bathrooms.

Opporting plates

Laying the slabs of the overlap is carried out after preparation of the project or the schema on which the product layout is performed. The elements of overlapping should be chosen so that their sufficient support is provided to the brick wall or clay-concrete blocks and styling without breaks in width.

Minimal support for PB series and PCs depends on their length:

• products up to 4 m long - 70 mm;
• products are more than 4 m - 90 mm.

Visual scheme of how correctly and how to make the wrong overlapping slabs

Most often, designers and designers take the optimal value of the wallpaper on a wall of 120 mm. This value guarantees reliability with small deviations when installed.

It will correctly be in advance to arrange the bearing walls of the house at such a distance so that it is easy to lay the plates. The distance between the walls is calculated as: the length of the standard plates is minus 240 mm. PC and PB series must be put up with a support for two short sides without intermediate backups. For example, PC 45.15 has a size of 4.48 m, it is deducted from it24 cm. It turns out that the distance between the walls should be 4.24 m. In this case, the products will be shared with the provision of optimal support.

The minimum support on the wall of products of the PT series - 80 cm. The installation of such reinforced concrete slabs is possible with the location of the poles on all parties.

Opportuning should not interfere with the passage of ventilation channels. The optimal thickness of the carrier inner wall of the brick is 380 mm. 120 mm on each side goes under the reinforced concrete overlap, and in the middle it remains 140 mm - the standard width of the ventilation channel. In this case, it is necessary as correct as possible. The displacement of the product towards the ventilating hole will lead to a decrease in its cross section and insufficient ventilation of the premises.

Summarizing said:

• pC series and PBs up to 4 m are based on two sides of at least 7 cm;
• pC series and PB more than 4 m - at least 9 cm;
• pT series - on two, three or four parties at least 8 cm.

Warehousing plates

Schemes for storage of products of different types

After the scheme has been developed and products purchased, they need to be located on the construction site for convenient installation into the design position. There are rules for the storage of materials:

• you need to lay items under a canopy;
• the place of the storage should be located in the area of \u200b\u200baccess crane;
• under the points of the support are supposed to links.

Failure to fulfill the last rule will lead to a different in half. PC products, PB and PTs work so that the appearance of intermediate supports or a solid base leads to the appearance of cracks. The laying is performed in the following order:

• wooden bars or boards under the edge of the plate are placed on the ground;
• on the board with a lifting crane from the machine by shifting the element of the overlap;
• on the stacked plate, boards or bars again;
• unload out the second plate from the car;
• repeat points 3 and 4, the maximum storage height is 2.5 m.

Requirements for masonry

Calculation scheme for floors

To properly install the floors of the overlap you need to ensure the performance of special requirements for the wall of the brick:

• equality of masonry at the site of laying overlaps;
• laying in three rows before the overlap of reinforcement grids with a cell 5 by 5 cm from a wire with a diameter of 3-4 mm;
• the top row to the vocabulary from the inside should be tychk.

If the plates are mounted on the ceramzite-concrete blocks, the monolithic belt is optional under the overlap. Such a design will help evenly distribute the load from heavy ceramzite-concrete blocks with less durability. Building technology provides for fill to blocks of monolithic tape from concrete thickness 15-20 cm.

Laying overlaps

For work, it will take at least three people: one performs the lines, and the two set them into the project position. If installers and craneer do not see each other, you will need another worker when installing the plate, which will serve the crane commands.

Concrete products laying scheme

The fastening to the hook of the crane is performed by four -roadwide sling, the branches of which are fixed in the corners of the plate. Two people stand up on both sides of the support and control its evenness.

When installing a PC pinching into the wall is carried out with a hard way, that is, on top and bottom, the plates are placed by bricks or blocks. When using overlaps according to the PB series, it is recommended to perform a hinged fix. To do this, the plates do not pinch on top. Many builders mounted a series of PBs just like PCs and buildings stand, but not worth the risk, because the life and health of man depends on the quality of the installation of carrier structures.

Another important feature of the use of products from the PB series is forbidden to make technological holes.

These punching are needed for conducting heating, water supply and sewage pipes. Again, many builders even during the construction of multi-storey objects neglected by this. The complexity is that the behavior of this type of overlap under load over time is not studied to the end, since there are no objects built for a long time. The ban on the punching of the holes has the base, but it is rather prophylactic.

Cutting plates

Sometimes to install the stove, it is necessary to cut it. Technology provides for carrying out works by a baccoon with a disc on concrete. Cutting the plates of PC and PT in length can not be, because in the support zones they have enhanced reinforcement. If you open such a cropped plate, then one edge will be weakened, there will be severe cracks on it. Cutting PB plates in length can be, this is due to the features of the manufacturer. Under the place of the cut laid a bar or board, which will make it easier for work.

The length separation is performed according to a weakened part of the section - a hole. This method is suitable for PC, but not recommended for PB, since the width of the walls between the holes is too small.

After installing the hole in the support zones, the walls are poured with light concrete or clog the mineral wool. It is necessary to provide additional strength in places of pinching into the walls.

What to do if it was not possible to decompose products in width

Sometimes the size of the room does not correspond to the width of the products, in this case all the gaps are driven into one. This space is overlapped with a monolithic area. Reinforcement occurs with curved grids. In length, they rely on the top of the overlap and as if they are saved in the middle of the monolithic site. For overlaps, concrete is applied not lower than in 25.

The technology of prefabricated overlap on the brick or blocks is quite simple, but requires attention to detail.

On the wall - one of the indicators of reliability, security and long-term service life of the building. Much depends on the competent installation of the plates, so all the rules and rules are governed by government agencies. There is a special document - SNiP, which collected the arch of these standards.

Purpose of overlapping

The floors are one of the main supporting structures of the building, so they are given enough attention during construction. The main function of reinforced concrete floors is the transfer and distribution of the load on its own weight, and then on other elements of the building.

At the location of these building structures are divided into inter beds, adventure and attic. Plates are manufactured in factory conditions and there are several types:

• collected-monolithic;
• multi-profile;
• made of heavy brands of concrete.

The main requirements that qualitative overlap must have strength, rigidity, non-controlling, sound and waterproof.

Most plates for overlapping are made with voids, such a design is considered the most optimal in weight and quality parameters. Laying occurs on the bearing walls of the structure, the step of which can be up to 9 m.

Parameters for the size of the content

The maximum and minimal support of the slab overlap on the wall is caused by the following factors:

1. The appointment of the building is a residential, industrial, administrative.
2. The material from which the bearing walls and their thickness are made.
3. The size of the overlapping span between the walls.
4. The size of the ZBB slab overlap and its weight.
5. Seismic indicators of the location of the building.

In accordance with the SNiP data, the support of the wall overlapping slabs is from 9 to 12 cm, depending on the factors described above. The final size is determined by engineers when designing a building. It is important to correctly calculate the magnitude of the adhesion, otherwise the floor pressure can lead to gradual cracking and destruction of the building.

Recording knot on a brick wall

When building buildings from brick, the laying is carried out close to the future ceiling, while it is important to leave small niches to install overlaps. The opening plate of the wall overlap on the wall is created taking into account the following conditions:

• furies plates should not rely on brickwork. For example, when inserted into 12 cm, a niche width should be 13 cm;
• the composition of the masonry and fixation of the floors should be identical;
• the voids formed in the channels should be filled with concrete liners. They are manufactured at the factory along with the plates.

The minimum supporting slabs of the overlap on the brick wall is not normalized in the event that the end walls of the zhb product lies with one side side. Installation is performed so that the masonry, which will be higher than the overlap, did not lie down on the formed extreme voids.

Installation of overlaps

Work on the installation of overlaps is carried out by a brigade of builders of four:

• crane driver that serves stove
• rigger running slabs,
• two installers engaged in coordinating the stove and room at a given place.

Opportuning slabs of overlapping on a brick wall at the same time is one of the most important procedures requiring strict compliance with standards.

Before conducting installation work, it is necessary to align the brickwork comb. If this is not done, the stove will be unstable. The gaps arising between the plates are sealed with cement mortar.

Features of flooring for buildings from aerated concrete

Opportuning overlapping plates on the wall is made on the ring reinforced belt, which is mounted by its perimeter. Such a monolithic concrete tape covering the entire building is required if the size of the content is less than 12 cm. The following parameters for Armopoyas are recommended:

• 12 cm thick;
• width 25 cm;
• superior depth is the same as for reinforced concrete floors.

In combination with durable reinforced concrete plates, the reinforced belt creates a rigid construction that has sufficient resistance to the structure of emergency effects, temperature drops and shrinkage deformations.

If the magnitude of the overlap on the wall is more than 12 cm, the building does not need the building in the additional reinforced belt. In such cases, it is enough to build a reinforced belt from the annular anchor on the outer perimeter of the plates.

Calculation of the Opproit Parameter

Regulates the size of the opening of slabs of overlapping on the walls of SNiP (otherwise, a set of rules and rules), which highlights the following blood sizes:

• modular - the width of the span, in which the design is installed;
• constructive - the real size of the ceiling plate from one end to another.

For example, if the modular length of the overlap is 6.0 m, the real - 5.98 m. To obtain the size of the room, 5.7 m should be installed slab with a content of 12 cm. The optimal calculation of the opening of the wall overlap plate is also important for saving Heat in the room. With too much intimacy of the end to the outer surface of the wall, cold air penetration will be observed inside. This design gives the cold floor in winter.

Overlapping ground floor

Installation of slabs of overlapping for the basement is the easiest. In order to achieve a flat surface for styling reinforced concrete structures, the top edge of the foundation should be aligned. Then, on the upper edge of the flooded foundation, formwork boards are exhibited. This design is poured with concrete solution. Thus, it turns out a perfectly smooth pillow for installing the plates.

The plates mounted on the smooth surface form a smooth ceiling, in which only seams should be seen, after which it is ready for decoration.

Sealing seams between overlappings

After the optimal size of the opening of the floor overlapping slabs was defined, and the reinforced concrete structures themselves are installed, you should close the seams between them.

For this, a sand-cement solution is used if the slots are insignificant. In the presence of large gaps, use the following ways:

1. Formwork is shutdown from wooden boards, into which the subsequent pouring of the solution occurs.
2. Large gaps can be embroidered with armature fragments, fragments of bricks and other materials. They are tamped in a slit, which are then embarrassed by concrete solution.

Educated voids when installing the plates, it is important to close at once. This greatly simplifies finishing works that will be made at the end of construction.

The future strength and durability of the structure depends on the correct calculation of the size of the opening of overlapping on the wall. Therefore, this process is regulated by the Rules of SNiP and is carried out by experimental designers.