Since in recent times prices for various Construction Materials are growing rapidly, you need to think about how to create efficient and high-quality buildings so that after construction you do not have to correct mistakes. In order to exclude possible mistakes and risks, during the construction of any buildings it is necessary to organize expansion joints in concrete. These designs minimize various deformations.
No exception here and various concrete structures. It can be floors, blind areas and many other structures. If the choice of technology for creating the floor is made incorrectly, then as a result it will be covered with cracks, and top coat deformed.
The condition of the foundation tape depends on the blind area. If it cracks, then this can cause moisture to penetrate into the base and eventually result in very serious consequences.
How do they look?
By appearance they are cuts in the concrete. Thanks to these cuts, cracking of the base will not occur with sharp and smooth temperature changes. This can be explained by the fact that the base can expand, there is enough space for this.
Yes, there is a large number of similar protective building structures. The SNIP classification contains not only temperature, but also many other types of seams.
Variety of concrete joints
So, among the seams are distinguished:
- Shrinkage;
- Sedimentary and temperature;
- Antiseismic.
Temperature-shrinkage seams are temporary lines. They are created mainly in monolithic structures directly during the pouring of concrete mixtures. As the mixture begins to dry, it will shrink. This may form cracks. So, the solution will shrink, and the pressure will act on the void line, which will expand. Then, when everything is dry, the line will be destroyed.
As for the second group, these grooves are designed to save the building from precipitation and temperature changes. Sedimentary seam can be found on any elements of the building, as well as at the base. The temperature notch can be found everywhere, on any elements, but not on the foundation. For example, in most buildings you can find expansion joints in the walls.
Anti-seismic protection are special lines that divide the building into blocks. Where these lines pass, they create double walls or special racks. This makes the building more stable.
Protects against sudden changes in temperature and deformation
By their own design features, temperature-deformation seam is a special groove, line. He divides the entire building into blocks. The size of such blocks and the directions in which the notch line separates the building are determined by the project, as well as by special calculations.
In order to seal these grooves, as well as to minimize heat loss, these grooves are filled with heat insulators. Often applied various materials rubber based. Thus, the elasticity of the building increases significantly, and thermal expansion will not be destructive to other materials.
Often, such a cut is made from the roof to the base. The very foundation of the building is not divided, since the foundation is lower than the depth at which the soil freezes. The foundation will not be affected low temperatures. The step of the expansion joint depends on the materials used, as well as on the point on the map where the object is located.
In most buildings and structures, you can use the numbers from the tables. The distance between the expansion joints will be 150 m for those buildings that are built from prefabricated structures and heated, or 90 m for heated monolithic structures.
Where is there no heating?
In this case, these figures are reduced by 20%. In order to prevent forces, in case of uneven settlement, settlement joints can be arranged. Also, this protection can play the role of temperature. The sedimentary section should be created to the base. Temperature - to the top of the foundation. The width of the expansion joint should be 3 cm.
Protection in homes where people live
The temperature seam in a residential building has ancient history. The use of these technologies began during the construction of the first Egyptian Pyramid. Then it began to be used in any stone structures. With the help of this trick, people have learned to save their homes from temperature fluctuations and other natural disasters.
The operation of residential buildings often leads to various types destruction of the base and foundation. Among the many possible causes you can distinguish the movement of the soil under the house. This is a signal of a violation of waterproofing. Subsequently, the house will collapse sooner or later.
How it's done
Every home has a perforator. So, with the help of a drill, you need to make a horizontal cut in the wall. Then it is necessary to seal the seam with roofing felts, tow, and at the end a special lock should be made from water, sand, clay and straw. This composition must be well sealed with a temperature seam.
And if the house is made of bricks
Here, such means of protection should be provided at the design stage. In order to equip the incision, a tongue is used in brickwork, which will be lined with two layers of roofing. Then everything is pulled together with a layer of tow and again it is required to cover everything with a lock based on water and clay.
- The sheet piling is created at the stage of building construction. However, if it is not available and is not provided, but to do this protective agent very necessary, then everything can be done with a puncher, but you need to work very carefully. What is a tongue? This is a technological breakthrough. The dimensions of such a recess are 2 bricks high and 0.5 deep.
- At this stage, it is necessary to overlay the future expansion joint in the brickwork with the same roofing paper and fill it with the same tow. Thanks to their unique properties these materials do not react in any way to temperature jumps, and the masonry, in turn, will not react to them either.
- Now it's time to close this groove. Most people use concrete or cement mortar. However, clay-based putty is much better suited for these purposes. Efficiency is due to the fact that clay is an excellent heat insulator and water insulator. Clay also has a decorative function.
We protect the blind area
So, in order to make expansion joints in the blind area, you must:
- Dig a trench along the length of the structure. Its depth should be 15 cm. The width of the trench should be greater than the roof peak;
- Pour a crushed stone pillow to the bottom of the trench, and lay roofing felt around the entire perimeter on top;
- Carry out the installation of the frame based on the reinforcement.
Before moving on to concrete work on the blind area, we will perform a protective seam. It should be done on the line where the walls and the blind area are connected. To organize the groove, it is enough to install boards of small thickness between the blind area and the wall. Also, these grooves are necessary and across. This is done in the same way. It is necessary to maintain a distance of 1.5 m.
After pouring concrete mix will get where it is needed, but where the boards are installed, grooves will remain. After sufficient hardening of the solution, you can pull the wood. Slots can be blown out with sealant or other means. The most important thing is that the incisions are not empty, otherwise the protection will be zero.
What about the concrete floor?
Expansion joints in floors can be made even after the mixture has hardened sufficiently. Of course, it is better to take care of them even before the pouring process.
To perform such protection in the floor, you need:
- Determine lines for cutting concrete. The distance can be easily and simply calculated. So, 25 must be multiplied by the size of the floor thickness;
- Cut grooves with a power tool. The depth in this case will be 1/3 of the thickness. Optimal dimensions in width - a couple of centimeters;
- Remove all dust from the grooves and prime;
- When dry, the slots should be filled with any material intended for this purpose.
These actions will not cause difficulties for anyone. What happened? If the floor is deformed, then these processes will go along the lines of the seams. Here the screed may crack a little, but the finish flooring stays perfectly intact.
It turns out that such events and simple technological operations, both on the street and in the house or any other building, allow you to protect the building. If once with inexpensive materials and a perforator to create an expansion joint in the slab, floor and anywhere, you can save a lot in the future and extend the life of the building.
An expansion joint in brickwork is necessary to ensure high-quality and effective protection of the building from premature destruction due to uneven shrinkage of the building or soil instability.
Competently and correctly created, it will help prevent cracks in the walls of the building and gaps in bearing walls Oh. To avoid cracking of the walls due to significant temperature changes, an expansion joint in the brickwork will help. The design of the expansion joint is given increased attention, since the strength and durability of the building depend on its implementation.
Kinds
Thermal seams must be made strictly according to the SNiP regulations There are several types of seams that increase the stability of the structure to various factors affecting its durability:
Temperature connections provide reliable protection from negative effect, which is caused by temperature fluctuations environment. Their device complies with the regulations of SNiP II-22-81, paragraphs 6.78-6.82.
Their peculiarity lies in the fact that such seams are arranged in accordance with the height of the walls, without affecting the foundation.
At a temperature of + 20 ° C in the hot season and -18 ° C or lower during the winter cold, it expands and narrows. Accordingly, its height changes. The range of such changes reaches 0.5 cm for every 10 m of height. It depends on the air temperature, but in any case, when creating them, they use a tongue filled with a tight, tight gasket in order to avoid blowing.
The width of the seam is from 0.1 to 0.2 cm, depending on the air temperature in each individual area.
Sedimentary joints help the building withstand heavy loads Sedimentary joints are designed to protect the load-bearing walls of the building from deformation and premature destruction under the influence of increased loads. It is these loads that lead to uneven shrinkage of the building and the appearance of cracks on the walls.
These defects occur most often during the construction of multi-storey buildings. Sedimentary expansion joints begin to form from the foundation of the house.
Anti-seismic seams are those whose device is mandatory in areas with increased seismic hazard. Soil mobility and tremors lead to significant deformations, which result in cracking of the walls and their subsequent destruction. The peculiarity of such seams is that with their help the building is divided into separate stable blocks.
To fill the seam, a heater, sealant and mastic are used, the density of which will ensure the quality of the device and withstand the upcoming loads.
The ability of the building to withstand deformations, its reliability and durability depends on the quality of the filling of the seam.
Device
The most common is the temperature expansion joint, since significant temperature differences become one of the most common causes, along which the walls of buildings crack and collapse. The width of the arranged seam also depends on the temperature level. 
In accordance with the regulations, it cannot be less than 2 cm, and in some cases reaches 3 cm. This is due to the fact that the expansion joints have sufficient horizontal mobility. The distance between the seams is at least 15 and not more than 20 m. In the hottest areas, this distance can be reduced to 10 m. For more information on the need for masonry joints, see this video:
The design is easy to install. The work is done with:
- harnesses;
- elastic fillers, characterized by the ability to maintain elasticity after hardening;
- bentonite or other substances that contain a small percentage of concrete;
- high elasticity sealants.
The construction of the expansion joint begins during the construction of the house. To do this, it is enough to retreat the required distance from the main masonry and fill it with insulation or sealant. The installation process will be easier if the depth of the sealant is small.
In reinforced concrete and stone structures of considerable length, dangerous self-stresses appear due to shrinkage and temperature effects, as well as due to uneven settlement of foundations. An example is the outer walls of buildings, which, with seasonal temperature changes, periodically receive increasing tensile or compressive strains. As a result, the walls of the building can break into two or more parts, depending on the length of the building. Additional stresses in structures from uneven settlement of supports arise when the foundations of buildings are placed on heterogeneous soils or when the pressures of the foundations on the foundations are not the same.
In order to reduce their own stresses from temperature differences, shrinkage of concrete and settlement of supports, reinforced concrete and stone structures of buildings are divided along the length and width into separate parts (deformation blocks) by temperature-shrinkage and settlement joints. Temperature-shrinkage seams cut buildings to the top of the foundation, and sedimentary seams - including the foundation. This is due to the fact that the temperature and humidity regime of the foundations fluctuates slightly, therefore, small self-stresses arise in it from shrinkage and temperature changes. In buildings from monolithic concrete expansion joints are at the same time working joints, i.e. places for stopping work on laying concrete for a long time.
Total Width expansion joints depends on the size of the deformation blocks of the building and possible temperature fluctuations. Calculations show that during the construction of buildings in conditions of average temperature, their deformation blocks can be separated by seams 0.5 cm wide; they can even come into close contact, since, due to the shrinkage of concrete, the seams themselves will open and form a gap sufficient to elongate the longitudinal structures of the blocks with increasing temperature. If the structures are erected at a relatively low temperature, then the width of the seam is usually taken as 2 ... 3 cm.
Buildings or structures that are rectangular in plan are usually divided by seams into equal parts. In buildings with extensions, it is convenient to place expansion joints in the incoming corners; with different number of storeys - in conjugation of a low part with a high one (Fig. 148), and when new buildings or structures adjoin old ones - at the junction. In seismic regions, expansion joints are also used as anti-seismic ones.
Expansion joints in enclosing structures are solved in a relatively uniform way, which cannot be said about the structures of the supporting frame. The most simple Constructive decisions temperature joints. In one-story buildings, this is achieved by installing paired columns.
expansion joints in frame buildings most often they are formed by installing double columns and paired beams (Fig. 149, a). Such seams are the most expensive and are recommended for buildings. elevated number of storeys under heavy or dynamic loads. In panel buildings, seams are performed by setting paired transverse walls. When resting the floor beams on the walls, it is advisable to arrange the expansion joint with the help of a sliding support (Fig. 149.6).
In monolithic reinforced concrete structures expansion joints are arranged by freely supporting the end of the beam of one part of the buildings on the console of the beam of the other part of the building (Fig. 149, c);
in cantilever expansion joints, the contacting parts must be made strictly horizontal, since otherwise, due to jamming of the seam, both the console and the part of the beam lying on it can be damaged (Fig. 150, a). Especially dangerous is the reverse slope of the supporting surface of the console. Exemplary designs of expansion joints in walls and ceilings are shown in fig. 150, in, city
Sedimentary seams (when new buildings adjoin old ones, in places where high parts of a building meet low ones, when buildings are erected on heterogeneous and subsiding soils) are arranged by means of paired columns based on independent foundations, or installed in the gap between two parts of the building (with independent foundations) loosely supported insert slabs or beam structures (Fig. 150.6). The latter solution is most often used in prefabricated structures.
A brick house is a reliable and durable housing. However, its walls are prone to deformation due to temperature fluctuations. The temperature joint in brickwork contributes to a significant reduction or prevention of possible cracking of the walls, maintaining their integrity. Such seams reduce the load on structural elements and make the masonry more resistant to fluctuations in air temperature.
What it is?
An expansion joint in brickwork is a special gap along the perimeter of the structure, which divides the wall into separate compartments, which gives the building elasticity. It is made in order to prevent cracks in building structure when expanding and contracting building materials under the influence of temperature differences, as well as for additional protection walls from deformation during shrinkage of the house. The size of the gap depends on the type of masonry and the ambient temperature at different times of the year, taking into account climatic conditions region. In multi-storey buildings, the temperature seam is:
- Vertical. It runs along the height of the entire house, with the exception of the foundation, the width is 20-40 mm.
- Horizontal. It is made at the level of all floors with a width of 30 mm.
The contact of the expansion joint in the brickwork with the foundation of the building is unacceptable.
Types of expansion joints in a brick multi-storey building
In the group of such seams there is a sedimentary type.
In addition to temperature, there are other types of expansion joints in masonry, such as:
- shrinkage;
- sedimentary;
- seismic.
All types of special gaps protect each structural unit of the house from destruction and prevent the formation of cracks in load-bearing and other walls. Temperature and shrinkage voids are made in all, without exception brick houses. Sedimentary ones perform a protective function against destruction under high loads and are needed in multi-storey buildings and houses with an extension. They are made starting from the foundation, but the device is made according to the principle of vertical temperature gaps, so it is possible to combine them into heat-shrinkable ones and create them in one firmware. It is expedient to make seismic voids only in areas with increased seismic activity.
Insulation and insulation options
In order to protect against environmental influences and prevent drafts inside the building, all deformation gaps without exception are insulated. For this, a protective hermetic layer is created using elastic materials. The choice of insulation depends on the size of the expansion joint. In this case, one type of material or a combination of them is used. The table shows the type of insulation depending on the width of the temperature gap in the brickwork:
For sealing insulated seams use:
Long-term experience of working with housing and communal services enterprises has shown the need for periodic explanations various technologies maintenance of buildings and systems of functioning of various structural elements buildings.
Types of expansion joints
Expansion joints are divided according to their purpose into temperature, shrinkage, settlement, compensation and seismic and represent a through section of the building into separate blocks to reduce the load on structural elements in places of various deformations.
In our climate zone, the first two types are most common. Expansion joints can be seen on houses with a length of more than four entrances, and sometimes more often, and they serve to increase the elasticity of the building in the off-season, when the ambient temperature changes, and hence the building.
Shrinkage joints are used primarily in houses consisting of sections of different heights, which means that they give different shrinkage after construction.
In other words, expansion and shrinkage joints are needed so that the building does not crack due to temperature fluctuations and during the shrinkage of the building.
Of course, the expansion joint must be protected from snow, moisture, dirt, and drafts inside it. To do this, the seam is insulated and sealed. The choice of material for insulation depends primarily on the width of the joint, and the method of sealing the joint depends on the planned service life and available Money for its repair.
The most obvious seems to be to fill the seam with a vilotherm and plaster, as is done on many new buildings. This method how simple it is, it is also short-lived, since the plaster in the expansion joint is not able to withstand the load placed on it and inevitably first cracks and then crumbles.
Vilotherm, on the other hand, showed its fragility in the absence of its combination with mounting foam.
Seam insulation options
Let's analyze possible options insulation and sealing, depending on the width of the seam.
With a small width, the use of classic polyurethane foam will be optimal; in a state protected from sunlight, it is inferior in durability only to expanded polystyrene.
With a joint width of 30 to 50 mm, a combination of polyurethane foam and viloterm will be optimal. Vilotherm will provide foam savings and add plasticity to the joint, and foam will create a margin of safety and will not allow the vilotherm to accept permanent form during the displacement of parts of the building, which means it will not allow the appearance of gaps in the expansion joint.
The question is natural - why is it impossible to completely fill the seam with mounting foam?
Firstly, with a projected joint width of more than 30 mm, a significant displacement of the building elements relative to each other is also taken into account, which means that it becomes necessary to ensure proper plasticity of the insulation.
Secondly, foam is much more expensive than expanded polystyrene and vilotherm, and, as a result, when the seam is completely filled with only polyurethane foam, the cost running meter will increase significantly.
Seam sealing options
The sealing of the temperature-shrinkage joint is carried out either with a two-component sealant, or it is sewn up with a galvanized expansion joint.
Sealant can be used on seams of small and medium thickness. It is important to use a two-component polyurethane sealant, as it is more flexible than acrylic sealants and is more durable. The disadvantage of this method is the relative unaesthetic, since a two-component sealant cannot be applied in a perfectly even layer due to its properties. Plus - the cost of the seam, since the application of sealant is less laborious than installing a compensator.
The use of sealant is most justified for shrinkage joints, especially for new buildings, where the displacement of building elements relative to each other has not yet passed its most active stage. The sealant will crack over time, but without damage to the building facade, especially if the building is insulated with the currently widely used “wet facade”.
The most durable way to seal the expansion joint is to seal the joint with a galvanized expansion joint. It is extremely important to use not just a galvanized sheet, but to use metallic profile with expansion joint reinforcement. Its service life is limited only by the aging of the metal. If you use simple galvanizing without a deformation bend, then over time it will be torn out of the wall due to the lack of minimum tensile elasticity.
Loading...