Monolithic belt for walls made of cellular blocks. Reinforced belt for aerated concrete

In this article, we will figure out why we need an armored belt on aerated concrete. The basic requirements for this structural element will be considered in detail, and you will also learn how to properly make an armored belt for aerated concrete on your own.

The armored belt for aerated concrete is a tape structure made of monolithic concrete, repeating all the contours of the building wall. In gas-block houses, this belt is a necessary element that significantly improves the strength characteristics of the entire building.

In order for the reinforcing belt not to be the weak link of the house in terms of thermal insulation, the technology provides for the creation of belts not for the entire width of the wall, but with an indent from its inner side.

In this case, the minimum width of the belt should be 25 centimeters for brick and 20 centimeters for concrete. The free space formed after pouring the armored belt is filled with heaters and closed with a foam block fitted to the size.

We will also give reviews of builders specializing in the construction of foam concrete houses, which will help you get a complete picture of the need to equip a reinforcing frame for expanded clay concrete blocks:

Igor, 49 years old, Moscow:

For the past seven years, my team has been using foam concrete as the main building material, and I have heard only positive feedback from customers about our work.

The number of fans of this material, since its appearance on the domestic market, has grown significantly. We install armored belts on aerated concrete in every house we have built.

I believe that the reinforcement frame is absolutely necessary for foam concrete, and the manufacturers' statements that the strength of the blocks is already enough for the installation of any floors do not correspond to reality. As for me, it’s better to play it safe once again and consolidate the work than to bite your elbows later.
Oleg, 45 years old, Rostov:

We build houses from gas blocks. We install the armoframe without fail, especially for hanging rafters and to fix the ceilings from concrete slabs. Recently, he built a utility room for poultry in his summer cottage, using a cinder block as a building material.

It was equipped with a brick reinforcement frame, because I am sure that the “doctor prescribed” it to be fixed to all buildings made of building materials based on foamed concrete.

2.3 Do-it-yourself armo-belt arrangement (video)

Comments:

When a house is being built, it is very important to have an armored belt for aerated concrete, which makes it possible to make the building structure more powerful, and the roof frame fastening more stable.

To date, one of the most economical, reliable and affordable materials for building a house is aerated concrete.

In this regard, when manufacturing an armored belt for aerated concrete, builders tend to make it with a minimum number of connecting seams in order to ensure the presence of a homogeneous material.

It plays an important role when connecting different types of material, such as wood with foam concrete blocks. The fact is that aerated concrete and similar materials have a porous structure. They are not able to withstand large loads if the point of application is small surface areas. In addition, this material cannot provide reliable fastening of floor beams. There is only one way out of this situation - an armored belt for aerated concrete. It has a special design designed for a variety of mechanical effects.

The entire perimeter of the house is surrounded by a monolithic belt, which has several more names:

• seismological;
• unloading;
• reinforced.

The design has the form of a ring, completely closed.

In the case of the construction of a two-story house, two are laid in the project. They will be located at the junction of the first floor with the second, as well as the roof with the second floor. But when a house is being built from aerated concrete, two belts are not enough. Another monolithic belt is laid, especially for the manufacture of the foundation.

Main characterizing points

1. Low cost of construction work. Aerated concrete house is much cheaper than a brick house.
2. Low weight.
3. Frost resistance.
4. Moisture resistance.
5. Resistance to aggressive environments.
6. Fire resistance.
7. The service life reaches 100 years.

If we compare aerated concrete with brick, we can find several negative aspects:

1. The structure is highly porous. It causes decompression of the structure and its subsequent destruction.
2. High quality waterproofing required.
3. Cracks may appear.
4. Wall reinforcement is required.
5. Foundation reinforcement required.

In addition, strengthening the house of aerated concrete blocks requires additional costs. In this regard, they try to strengthen the walls next to the foundation or after laying each subsequent row of blocks.

During operation, the building experiences a variety of loads:

• strong wind;
• temperature jumps;
• deformation due to low soil density.

Such negative properties are corrected by a monolithic belt.

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Application and features

The reinforcing belt has several especially important functions:

1. Protection of wall structures from possible deformation, due to the movement of the soil, which occurs during the change of seasons, when uneven shrinkage of the building is observed.
2. Provides extra strength.
3. Strengthens the structure, makes it more rigid.
4. Thanks to the monolithic belt, the load is evenly distributed.
5. Point loads are removed if the beams were anchored with anchor bolts.

The constructed unloading belt must necessarily look inextricable, since its main purpose is to increase the resistance of the walls of the building to loads that will cause cracks. The monolithic belt is built mainly in buildings where gas silicate blocks are the building material.

And what are the reasons for the construction of a reinforcing belt? The beam supporting the entire roof truss system is called Mauerlat. With its help, the roof is connected to the wall of the building. As a result, there is a uniform load on all wall surfaces of structures. In the case of fastening the roof structure with anchor bolts, point loads appear. Cracks appear in aerated concrete. When hanging rafters take place, an increased load occurs, which is perceived by aerated concrete blocks. As a result, they expand. To create a uniform distribution of such a load, a monolithic belt is made.

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Highlights of the work

1. Formwork. Usually such a formwork is a frame, which is made of wooden boards. They are fastened on the outside with small slats. This method of manufacturing formwork is considered the simplest and most in demand. For a monolithic belt, it is quite enough to have a height of 30 cm. The thickness should be much greater than the width of the wall. The base of the wooden formwork is attached to the wall with self-tapping screws. From above, with a step of 80 cm, transverse ties are fixed. They are also made from wooden boards. Such fasteners are required, since the mass of poured concrete can crush the entire structure. When insulating a reinforced belt, professionals recommend moving the formwork a little deeper. The resulting niche is then filled with thermal insulation.
2. Frame. If it is planned to make floors without the use of concrete slabs, it is quite enough to make a frame using a pair of reinforcing bars, which are interconnected by jumpers. The frame will take the form of a ladder, where the step of the jumpers will be equal to 50 cm. To apply more serious loads, the frame must have increased reliability. In this case, four reinforcement bars are taken, which are connected by jumpers. If you look at such a structure in a section, you get a square or rectangular structure. For any version of the frame, it must be set in such a way that the wall is at a distance of more than 5 cm from the frame. Aerated concrete blocks should not be connected to the armored belt. To do this, the gap between them is laid with fragments of brick. Welding of the reinforcing cage must be done directly in the formwork. The fact is that the finished frame has a very large weight. It will be difficult to lift and install accurately. The correct installation of the frame is checked by the building level.
3. Pouring concrete. After all the preparatory work, the unloading belt is poured. For this, a ready-made concrete solution is used. It can be purchased at every specialized store. For this, cement grade M200 is used. If desired, concrete can be made independently. There are practically no difficulties in the manufacture of concrete mortar, but the work is highly labor intensive.

For work you will need:

• cement;
• sand;
• rubble.

Usually a ratio of 1:3:5 is taken, water is added. Everything is thoroughly mixed until the desired consistency is obtained. For such work, you will need a lot of concrete, therefore, in order to save your strength, you should use a concrete mixer.

Armopoyas on aerated concrete is a reinforced concrete structure that serves to strengthen the walls of houses. An armored belt for aerated concrete is installed around the entire perimeter of buildings and structures so that it increases resistance to temperature changes, subsidence of the soil under the structure and resists the force of the wind. It is also advisable to use an armored belt on aerated concrete when building houses on sloping terrain.

purpose

The armored belt is used to strengthen the house around the entire perimeter, as well as:

• In the case when the aerated concrete structure is not able to withstand the loads when using point fixings for the roof frame. Cracks and chips form on the plates.
• With a design with a hanging roof frame, a load is obtained on brick and aerated concrete walls. In this case, the reinforcing screed plays a big role and will not allow the house to “burst at the seams”.
• When the beams of hanging roofs, which are attached to aerated concrete material, carry a point load, which leads to a weakening of the strength characteristics of buildings and structures. Cracks, chips, destruction are formed. To avoid this, they strengthen the points with loads and the place under the roof with the help of an armored belt.

A reinforcing belt made of reinforced concrete is used in the case of:

• wall deformations due to movement and unevenness of the soil;
• the need to provide additional strength to buildings;
• the need to distribute loads along the walls;
• prevention of point loads due to the fixation of beams to the camps of buildings and structures using studs and anchor bolts.

The armored belt for aerated concrete must be integral, since it plays a large role in the duration of the service life of buildings, which means it must increase the strength of the walls' resistance to various loads.

Where is it installed?

They begin fixing the armored belts on aerated concrete by determining its location. The area of ​​application should be selected based on its main function - increasing the strength characteristics of buildings where there are negative living conditions and soil buoyancy.

The reinforced concrete one-piece structure includes several belts. To make the first belt, install the upper part of the foundation. Filling occurs under the tape. Using the second belt, the installation is above the supports. This design is the basis for the supporting foundation.

The first grillage is 350 mm high and 1000 mm wide. These dimensions are approximate, as they are affected by environmental conditions:

• humidity;
• temperature regime;
• soil change.

It should be located along the perimeter of structures and under load-bearing walls. Such a basis will ensure the reliability of buildings and structures. A second reinforcing belt is installed with a height of 300 mm and a width the same as that of the wall. The use of a second layer is optional.

The third layer is placed under the barrier slabs. It provides a coupler of walls and interferes with formation of cracks. The fourth one is used in the construction of brick and aerated concrete structures and is installed for barrier slabs on the second floor.

Device methods

They begin construction work with the calculation of the size and shape of armored belts. There are two ways to make an armored belt for aerated concrete:

• using formwork;
• using gas blocks.

When installing tie-down structures, the following materials and tools are used:

• roulette;
• concrete mixer;
• boards;
• fittings;
• mallet;
• equipment when working with aerated concrete;
• fasteners;
• glue;
• concrete mixer;
• concrete mortar and ingredients for its preparation;
• insulation;
• stone.

With formwork

Before starting, a wooden formwork is made. After its installation, the reinforcing structure is mounted and everything is poured with concrete. The formwork is applied in the form of U-shaped blocks. At the end of the work, the resulting structure is covered with an insulating layer, due to which the heat output through the reinforcement is reduced.

Materials and tools

To make formwork, the following materials are used:

• Boards with a flat surface.
• Plywood, which must be moisture resistant. To ensure it, the plywood surface is treated with a coating based on polymeric materials.
• Warming material. Which has a small volumetric weight and is resistant to mechanical stress.

Required tools:

• building level;
• hammer;
• roulette;
• hacksaw;
• boards of various sizes;
• plumb;
• drill;
• self-tapping screws;
• wire;
• mount.

Formwork installation

Mount the formwork begin at the same time around the entire perimeter of the structure. They begin to fix the formwork with screws or nails. After that, the spacer is attached to the shields and, to increase strength, connect them together with wire. To provide heat in the building, the inner layer of the formwork is laid with a heat-insulating layer.

After assembling the frame, a building level is used to ensure evenness of the structures. To give a good bunch of gas blocks with an armored belt, a number of nails are driven into their top layer even before the pouring stage.

Reinforcement installation

Installation of fittings is possible from two and four rods. Using the first option, concrete slabs are installed in increments of half a meter. In the end, the frame will resemble steps. This design is suitable for foundations with light loads.

For more complex and heavy options, a base of four rods is used, which is also connected by jumpers. As a result, the design will be in the form of a four-sided figure. When installing reinforcement, a five-centimeter distance from the edge of the structure must be observed. The connection of the elements is carried out with a wire intended for tying the reinforcement, but in no case by welding.

fill

As soon as the work on the installation of the formwork is completed, they begin to pour concrete mortar into a monolithic frame. The concrete mixture includes the following components:

• sand;
• crushed stone;
• cement;
• water.

Using a concrete mixer, thoroughly mix the ingredients until a homogeneous structure is formed. Formwork is poured in one step. After that, the formed air bubbles are removed with the help of tamping mechanisms. The monolithic layer is laid with insulating material.

Armopoyas (reinforced reinforced concrete belt) aka seismic belt- a very strong monolithic strip along the perimeter of the building and load-bearing walls made of aerated concrete.

Tasks of the armored belt - significant strengthening of load-bearing walls to increase their bearing capacity, to avoid cracks and other deformations due to uneven shrinkage of the building, roofing, wind and other loads.

The armored belt securely fastens aerated concrete blocks, evenly distributes the load and creates structural rigidity.

Ideally, the geometry, reinforcement and composition of the concrete of the armored belt is determined by calculations.

Usually the width (thickness) of the armored belt equal to the width of the wall, 200-400mm, and the recommended height is 200-300mm.

But it would be wiser to make the width of the armored belt a little thinner than the wall, so that there is a reserve of space for insulation, to reduce cold bridges. Extruded polystyrene foam (EPS) is best for this business, as it isolates heat perfectly. There is also the option of pouring the armored belt into ready-made aerated concrete U-blocks, but see more about this later in the text.

1. With uneven shrinkage of the house, with seasonal heaving of the soil, during earthquakes, the armored belt holds the geometry of the building.
2. Armopoyas can align walls horizontally.
3. Giving rigidity to the entire building of aerated concrete.
4. Local loads are distributed evenly on load-bearing walls.
5. The high strength of the armored belt allows you to attach all critical structures to it, for example, a Mauerlat.

Mauerlat must be firmly attached to the load-bearing walls with studs and anchors. The rafter system itself, the weight of the entire roof, snow and wind loads create a significant bursting force that can break unreinforced walls. The armored belt under the Mauerlat solves this problem, and it will be performed in the same way as under the ceiling.

1. The frame of the belt reinforcement must be continuous.
2. Armopoyas should be on all load-bearing walls.
3. The overlap of the longitudinal reinforcement is at least 800 mm.
4. The frame is made of two rows of reinforcement, two rods each.
5. The minimum thickness of the longitudinal reinforcement is 10 mm.
6. It is advisable to use long (6-8 meters) reinforcement bars.
7. The diameter of the transverse reinforcement is 6-8 mm.
8. Step of transverse reinforcement - 200-400 mm.
9. Reinforcement on all sides must have a protective layer of concrete of at least 5 cm.
10. The longitudinal and transverse reinforcement is connected to each other with a knitting wire.
11. At the corners, the longitudinal reinforcement must be bent, and try to overlap further from the corner.
12. The frame must be strictly horizontal.

Calculate the distance between the reinforcement bars according to the thickness and height of the armored belt, taking into account the protective layer of concrete, at least 5 cm on each side.

Do-it-yourself armored belt for aerated concrete (video)

Scheme of reinforcement of corners and junctions of the armored belt

Armo-belt insulation

The armored belt is a very serious "bridge" of cold, through which most of the heat escapes, and on which condensation forms from the inside of the armored belt. And to avoid this, it is necessary to insulate the outer side of the armored belt with aerated concrete, or polystyrene foam or polystyrene. Expanded polystyrene is more preferable. So in advance you need to provide space for insulation, filling in the armored belt with an indent from the outer edge of the wall.

Insulated armored belt for aerated concrete

What brand of concrete to fill the armored belt

For pouring the reinforced belt on aerated concrete, concrete grade M200-M250 is used. It can be brought ready-made with a mixer from the factory, or you can make it yourself.

Proportions for concrete grade M200: cement M400, sand, crushed stone (1:3:5). Proportions for concrete grade M250: cement M400, sand, crushed stone (1:2:4).

There should be a minimum amount of water in concrete, and to give plasticity, use a plasticizer.

The water-cement ratio should be in the range from 0.5 to 0.7, that is, 5 to 7 parts of water per 10 parts of cement.

Adding too much water to concrete makes it less durable.

To remove air bubbles from concrete, it should be vibrated with a special building vibrator, or the liquid concrete should be intensively and for a long time pierced with a piece of reinforcement.

Concrete must be poured into the formwork at one time so that it is monolithic (inseparable).

Proper, competent installation of floors is a guarantee of a reliable, long-term service life of buildings. For buildings made of blocks (aerated concrete), additional support is required - reinforcement. The armored belt in a house made of aerated concrete is a special additional structure that is mandatory when installing floor beams and roofs. The manufacture of reinforced belts, for houses made of cellular concrete, the installation of ceilings is regulated by SNiP. Here are the brands and characteristics of the beams, the necessary parameters for supporting the walls, from what and how it is made. Compliance with these standards is directly related to the structural stability of building structures.

Armopoyas is an indispensable element in the construction of a house

What is an armored belt for?

A structure made of aerated concrete material will not be able to withstand high loads (shrinkage of the building, sedimentation of the soil under it, daily temperature changes, seasonal changes). As a result, the blocks crack, collapse. To avoid various kinds of deformations, monolithic reinforced concrete fixtures are installed. The reinforced belt takes these loads on itself, distributes them evenly, ensuring the reliability of the structure, and binds the walls into one.

It is also needed to distribute the vertical load. Giving the structure rigidity, it does not give rise to floor movement (aerated concrete blocks expand with the movement of moisture, steam). For this, he also received the name - unloading, seismic belt. Another purpose of armored belts is to protect the edges of the upper blocks from destruction (installation of interfloor ceilings). Remove the point load of beam wooden frames when constructing a roof. Given these qualities, the armored belt is mandatory for beams, floor slabs of the second (subsequent, roof) floor in a house made of aerated concrete blocks.

An armored belt is needed to evenly distribute the load on the foundation and walls

During the construction of one-story buildings, the question often arises whether an armored belt is needed for a one-story house made of aerated concrete. This element is simply necessary if:

support beams (Mauerlat) are installed on which roof rafters are attached, this is especially true for projects of one-story houses with an attic;

the foundation is made on unstable ground to bind the entire structure into one (bearing) system.

A prerequisite for houses made of aerated concrete blocks is the complete looping of the belt. The outline of the structure must be without breaks. Refusing to use the armored belt, the appearance of cracks is inevitable. Even despite light wooden floors and masonry reinforcement from aerated concrete blocks.

Unlike brick structures, for a house made of aerated concrete, the reinforcing belt must be made in a single ring

Interfloor reinforced belt

This type of construction is performed for slab or beam floors. The main purposes of ceilings include the perception and transfer of the load of its own weight, interior, people to walls, dividing the internal space of buildings into floors, overlapping spans. This is a load-bearing structure that rests on the outer and inner walls around the entire perimeter.

The basis for pouring the armored belt is the supporting surface of the bearing walls, which perceives the entire mass of the future structure. General requirements:

installation is carried out on the entire perimeter of the future building, taking into account the internal walls;

for external load-bearing walls, blocks with a density of at least D-500 are used;

height, made according to the height of aerated concrete, or less is allowed (200-400 mm);

belt width - 500 mm (reduction by 100-150 mm is possible);

the reinforcing cage rests on supports (brick, pieces of blocks, plastic clamps) 3 cm high so that it does not touch the walls, thus creating a so-called protective concrete layer;

for pouring, concrete not lower than grade B-15 is used.

Formwork for pouring concrete mortar with reinforcing mesh

On our website you can find contacts of construction companies that offer foundation repair services. You can directly communicate with representatives by visiting the exhibition of houses "Low-Rise Country".

Armopoyas for aerated concrete under floor beams, poured into a pre-prepared formwork. This frame is made from:

Plastic.

aluminum.

3. Blocks of aerated concrete.

This type of formwork is used most often. This is the cheapest and most popular option. By installing a double-sided removable wooden frame (shields made of wood), it is fixed with self-tapping screws on both sides of the wall (to aerated concrete blocks). The upper part is pulled together with wooden lintels (step 800-1000mm). This is necessary so that the concrete does not push the structure apart when pouring.

Wood formwork is the most common option due to its availability.

The reinforcing cage (reinforcement diameter 8-14 mm), made in the form of a "ladder" (connection with jumpers with a step of 5-7 cm), fits into the prepared space. The rods are knitted together using a knitting wire (every half a meter), forming a square shape. It is not recommended to use welding, because of the rusting of the welds in the concrete. For beam ceilings (at a low load), a frame of two rods is enough, with a monolith height of 30 cm. For overlapping with slabs, an armored belt with increased reliability is used (4 rods and a monolith - 40 cm).

After removing the formwork, the outer wall is insulated along with the armored belt. If during finishing the outer walls are only plastered, then to remove the “cold bridge”, the formwork is moved deep into the wall. And in the resulting niche, then a heater is installed.

You can use one-sided removable formwork. In this case, aerated concrete blocks (10 cm thick) perform the external function. They are stacked on the bottom row, using glue. A wooden frame is attached to the inside. After that, insulation (5 cm) and fittings are laid. The top is also pulled together with jumpers.

Video description

How to make a wooden formwork for an armored belt:

Belt using blocks

The manufacture of such formwork requires additional additional blocks or ready-made U-shaped aerated concrete products. In this case, on the glue (on top of the previous row), internal (thickness 5 cm) and external (10 cm) or U-blocks (with walls - 5 and 10 cm) are installed. In the inner space, fittings and insulation are placed (to the outer wall). After that, the concrete is poured. For openings (doors, windows), at the level of the top of the previous row of masonry, wooden lintels are installed. They are fixed with vertical supports.

This type of formwork is relatively easy and quick to install. But it is not very popular due to the need to purchase additional material, and as a result, an increase in the cost of construction.

An armored belt with the help of concrete blocks will be more expensive, but with their help the place of reinforcement will not be noticeable

Mauerlat belt

This armored belt is installed from the bottom of the attic, both for one-story and for two or more storey buildings. It is necessary for installing fasteners under the Mauerlat, and takes the main load from the truss system (vertical forces aimed at breaking) and the load from snow and wind. The installed fasteners for the beam are simply in aerated concrete, they will not withstand these loads. They will loosen (due to the low strength of the blocks) and the Mauerlat will move from its place, which will inevitably lead to negative consequences. It also acts as an additional reinforcement of the walls, preventing them from cracking.

Such a belt can be made of reduced dimensions due to the thickness (having correctly calculated the load) and two reinforcing bars can be used for the frame. A distinctive feature of such an armored belt are vertical studs with nuts. They are installed together with the reinforcing cage, before pouring concrete. It is on these mounts that the Mauerlat will be installed, which is fixed on top with nuts. This is the future basis for the roof truss system.

In the same way, you can make an armored belt in a house made of aerated concrete and under wooden floors. Pre-prepared fasteners for wooden structures will avoid subsequent drilling of concrete for the installation of anchors.

Pouring concrete

To fill the belt, after all the preparatory work has been completed, ready-made concrete (M200) is used or it is made on site in a ratio of 3-5-1 from:

• cement (M400).

Filling is carried out not in parts, but completely around the entire perimeter. If such a process is impossible, the necessary jumpers are made in advance. Before pouring the next batch of concrete, temporary lintels are removed, the joints are wetted with water and poured with concrete. The solution is sealed with an iron pin, removing air bubbles from it. During the hardening process (approximately 5 days), the concrete is poured with water to increase strength.

Video description

Preparation of a solution for pouring an armored belt:

Conclusion

A reinforced concrete monolithic belt, made according to all the necessary parameters and rules, will give the house of aerated concrete blocks the necessary strength and durability. It will protect the walls from premature cracks, will make a reliable roof.