Fiber foam concrete blocks. Construction of monolithic houses from fiber foam concrete Construction of houses from monolithic fiber foam concrete
Building a house today is easy and simple. Technologies allow this to be done quite quickly and at an affordable price. The most popular building materials for construction individual houses today are foam concrete blocks, aerated concrete blocks and fiber foam concrete.
A house made of aerated concrete blocks is fast!
They began to build houses from aerated concrete back in the 1980s of the last century, and today this material has long surpassed classic brick in its consumer qualities. Compare for yourself - the main advantages of aerated concrete are low thermal conductivity, high heat resistance, noise insulation and frost resistance. Aerated concrete blocks are lightweight, which means there is no need to build a powerful foundation. And the price of a house made of aerated concrete is within the capabilities of almost everyone.
Gas block with cladding and insulation - 6955 rub/m2 finished wall(working with materials)
Fiber foam concrete - durable!
Houses made of fiber foam concrete are built to last for centuries. Fiber foam concrete does not have the disadvantages of aerated concrete, since this material is made from foam concrete reinforced with synthetic or natural fibers. Buildings made of fiber foam concrete are capable of retaining heat 20–30% stronger than other building materials. Fiber foam concrete is able to control the microclimate in the room: in summer it is cool in such a house, and in winter it is warm and dry. In terms of its environmentally friendly properties, fiber foam concrete is second only to wood. At the same time, it has no equal in terms of durability.
The composition of fiber foam concrete includes high-quality cement, selected sand, fiber (reinforcing polypropylene threads) and an air-entraining additive (foaming agent) to create a porous structure.
A wall made of fiber foam concrete with a thickness of 30 cm can provide heat savings comparable to brickwork two meters wide. At the same time, fiber foam concrete is the only building material that, with a minimum width of masonry without insulation, meets the requirements of modern SNIPs for heat conservation. And the sound absorption quality of fiber foam concrete is proven by the following example - when interior wall 20 cm thick, you can’t hear any sounds from the next room at all.
A monolithic house made of fiber foam concrete is ideal in everything! This is the best value for money!
Fiber foam concrete - 5900 rub/m2 of finished wall (work + materials)
Today's know-how is monolithic construction from fiber foam concrete. The advantages of this method of building a house are obvious.
Firstly , you save by eliminating the process of laying blocks. Using monolithic housing construction technology, fiber foam concrete is poured directly into ring masonry, removable or permanent formwork.
Secondly , the integrity of the house frame is ensured - there are no joints that allow drafts to pass through, no use of mortar that creates voids in the walls, no “cold bridges.”
Third , the walls of the house at monolithic filling made from fiber foam concrete, they are smooth and even, which means they do not require additional plastering work.
Fourth , houses made of fiber foam concrete are fireproof. The Ministry of Emergency Situations recommends the use of fiber foam concrete walls at facilities where there is a risk of fire. Fiber foam concrete has the first degree of fire resistance, does not emit harmful and toxic substances when exposed to open fire and retains the strength of the structure.
Fifthly , monolithic house made of fiber foam concrete - light and stable. It can be erected on almost any site, providing all the required quality characteristics. Price monolithic house made of fiber foam concrete with a facade made of facing bricks is much cheaper than a similar house made of aerated concrete blocks with insulation and brick cladding. And the quality and durability of fiber foam concrete are many times higher than the characteristics of any other building material.
These are the main advantages of using fiber foam concrete. In addition, it can be noted that when building a monolithic house from fiber foam concrete, you do not need to spend money on transportation costs for delivering blocks to the construction site - fiber foam concrete is produced directly on the construction site.
Our company produces fiber foam concrete in full accordance with the approved technological process on high-tech equipment. All components of the solution are imported and of the highest quality. Fiber foam concrete is foamed with special blades at certain speeds. In its production, a specially developed foaming agent is used, which ensures highest quality fiber foam concrete.
We build houses from fiber foam concrete - with high quality, quickly, easily and at the most affordable price!
The construction company "SK-Absolut" provides a full range of services from design to construction of houses and cottages using monolithic construction technology from fiber foam concrete.
When constructing facilities, we use the most modern equipment to ensure high-quality work.
The technology does not require the use of lifting mechanisms, makes it possible to reduce construction time and implement architectural solutions of any complexity.
Fiber foam concrete is used as the main material for construction - foam concrete with the addition of polypropylene fibers.
Houses made of fiber foam concrete are equally good in both cold and hot climates. Characterized by low thermal conductivity and being vapor permeable, they provide comfortable living. Due to natural ventilation The house has a healthy, pleasant microclimate. The materials used are non-flammable, environmentally friendly, and excellent sound insulators.
What are the advantages of fiber foam concrete?
Reliability
Fiber foam concrete is an almost eternal material, not subject to the effects of time, does not rot, and has the strength of stone. Increased compressive strength allows the use of products with lower volumetric weight in construction, which further increases the thermal resistance of the wall.
Heat
Due to their high thermal resistance, buildings made of fiber foam concrete are able to accumulate heat, which during operation can reduce heating costs by 20–30%. High geometric accuracy of product dimensions allows you to avoid “cold bridges” in the wall and significantly reduce the thickness of the internal and external plaster. The weight of fiber foam concrete is 10% to 87% less than standard heavy concrete. Significant weight reduction results in significant savings on foundations. In the diagram on the right you can see a comparison of the thicknesses of single-layer enclosing walls according to SNiP-N-3-79 and SP 41-99.
Microclimate
Fiber foam concrete prevents significant heat loss in winter and is not afraid of dampness. The pores of fiber foam concrete, unlike aerated concrete, are closed, this allows you to avoid too much high temperatures in summer and regulate the air humidity in the room by absorbing and releasing moisture, thereby helping to create a favorable microclimate.
High installation speed
The house is installed without the use of lifting equipment due to the lightness of the structural parts and unique mobile equipment for pouring fiber foam concrete. The work does not require large amounts of time and labor costs- a two-story cottage structure can be assembled by a team of six workers in 10-12 days.
Soundproofing
Fiber foam concrete has a relatively high ability to absorb sound. In buildings from cellular concrete current sound insulation requirements are met.
Environmental friendliness
During operation, foam concrete does not emit toxic substances and is second only to wood in its environmental friendliness. For comparison: the environmental friendliness factor of cellular concrete is 2; wood - 1; bricks - 10; expanded clay blocks - 20.
Economical
Fiber foam block has a high geometric dimensional accuracy of products (+1mm) and can significantly reduce the thickness of internal and external plaster, as well as the total consumption of masonry mixture. The weight of foam concrete is 10% to 87% less than standard heavy concrete and brick, so there is no need to make powerful and expensive foundations.
Fire safety
Products made of fiber foam concrete correspond to the first degree of fire resistance; when exposed to open fire, they do not lose strength and do not emit harmful substances. The Ministry of Emergency Situations is recommended for fire walls, including those at storage facilities for highly flammable materials.
Transportation
The ratio of weight, volume and packaging makes all building structures convenient for transportation and allows full use of transport capacity.
Wide range of applications
In addition to walls, fiber foam concrete is used for heat and sound insulation of roofs, floors, insulation of pipes, production of prefabricated blocks and partition panels, floors and foundations.
Blocks based on foam concrete with the inclusion of fiber have become very popular with modern builders. This is due to the fact that this material has a number of positive qualities, which are so necessary for the walls of the house. However, it is worth remembering that fiber foam concrete is a product made of sand, cement and fiber-based foam material, which means it also has its disadvantages associated with the production technology and the components used.
Properties and scope
To begin with, it is necessary to say that the materials of this type are manufactured by certain companies. Therefore, it is worth talking about product quality based on general characteristics, and not based on a specific batch. Taking this into account, we will consider fiber foam concrete as a separate product created without violations technical process ().
Characteristics
First of all, it is worth saying that this type of material can safely be called the most environmentally friendly. It is assigned index 2, while wood is in first place and brick in tenth ().
At the same time, fiber foam concrete does not require additional processing, which would reduce this indicator, which cannot be said about wood, which requires impregnation and protection from fire.
- Special attention should be paid to the fact that products made from this material can have different dimensions. Large blocks are especially in demand, as they significantly reduce installation time and simplify it. Also, when making them, you can take into account some features in advance and create additional forms, which will completely eliminate diamond drilling holes in concrete or reduce their number to a minimum.
- It must be said that this material retains heat well, but it should not be used without additional insulation. The fact is that fiber foam concrete blocks do not have a homogeneous structure, since the air bubbles in them are randomly located and have different sizes. It is because of this that it is worth installing at least thin insulation so that the insulation is uniform, although in regions with a warm climate this may not be necessary.
- Properly manufactured foam fiber concrete has excellent antibacterial properties.. It is not afraid of mold or mildew, but professional craftsmen still advise adding a primer with similar additives to the solution or performing subsequent processing.
- Usually, the disadvantages of fiber foam concrete are not as pronounced as the advantages. They consist in relatively low strength. Moreover, this material is quite suitable even for the manufacture of three-story houses.
- It is also worth saying that these blocks are very easy to process.. By choosing them to create walls, you can avoid such a process as cutting reinforced concrete with diamond wheels.
Advice! By purchasing a batch similar material, it is worth asking the seller or manufacturer for a quality certificate. It must describe all declared characteristics and their compliance.
Application area
Considering that such blocks are light in weight, they are often used to make interior partitions or lintels.
- Many craftsmen use this material to create small buildings and houses. The fact is that its price and properties make it possible to save money and solve a number of problems related to insulation and environmental friendliness.
- It is not recommended to use such blocks for making a foundation or plinth. Typically, the installation instructions suggest using more durable products in such cases.
Advice! This type of material should not be confused with aerated concrete, since they have completely different characteristics, which naturally determines their scope of application.
- When doing the work yourself, it is worth remembering that these blocks have a certain absorbency, and therefore the solution is made slightly liquid.
- It is worth remembering that each manufacturer of these materials has its own system of standards, which does not always coincide with popular dimensions. Therefore, when ordering blocks, you need to know their size in advance.
- Should not be left finished goods made of such material without appropriate finishing. She will not only decorate appearance, but will also serve as additional protection.
Conclusion
By watching the video in this article you can learn more about this type of building material. Also, based on the text given above, it is worth concluding that for small buildings such blocks are the most optimal and can be completely used without insulation ().
However, it must be remembered that fiber foam concrete does not have a very good appearance and needs additional finishing. At the same time, its technical characteristics allow you to save a lot of money, which is completely justified.
In conditions modern market, the features of which are determined by the strict framework of the economic crisis, increased demands are placed on such factors as the cost of construction, the heat and sound insulation efficiency of the materials used and their consumption per unit of construction volume, operating costs, labor intensity and construction time of buildings. Therefore, the use of some building materials, previously widely used in construction, has become unprofitable under current conditions. Research conducted by specialists has revealed that the use of materials such as brick and concrete is uneconomical due to the excessive weight of the resulting structures (the volumetric weight of brick is 1400-1800 kg/m3, cinder concrete 1000-1800 kg/m3, reinforced concrete 2500 kg /m3), which forces you to make a more massive foundation and leads to higher construction costs. In addition, the construction of brick walls is associated with high labor costs and long construction times, and when using fully prefabricated concrete structures there is a need to use expensive equipment with a large load capacity. In addition, these materials have too low heat-protective and sound-proofing characteristics that do not meet modern requirements building codes and rules. According to previously valid thermal engineering standards for Rostov-on-Don, the thickness of walls made of brick = 510 mm was considered sufficient, and of expanded clay concrete 400 mm, according to the requirements of the new standards, for a residential building the thickness of the wall is from hollow brick should be 1470 mm, and from expanded clay concrete or pumice concrete 1090 mm. It is impractical to build walls of such thickness, so there is a need for additional insulation and sound insulation with other materials in order to meet thermal requirements with a more acceptable thickness of the enclosing structures. This complicates the production technology construction work, increasing material consumption, cost and construction time of buildings. Therefore, the use of these materials is considered ineffective. According to experts, materials such as gas and foam concrete have a much greater degree of efficiency and competitiveness.
Technology for the production of factory products from autoclaved aerated concrete has been constantly improved over 50 years, and its current level makes it possible to erect buildings with great speed and good quality. This material, which uses aluminum powder to form a cellular structure, undergoes autoclave processing in a factory, after which it is sawn into blocks ready for construction with strength sufficient to erect walls of buildings up to three floors high. This material has a low volumetric weight (the most commonly used is aerated concrete, with a density of 600 kg/m3), and has significantly better heat-insulating and sound-proofing characteristics than brick and concrete ( standard thickness aerated concrete block– 400 mm is sufficient to meet the required heat transfer resistance). The disadvantages of autoclaved aerated concrete are: destruction under the influence of dynamic loads, requiring mandatory lining for protection from mechanical influences; poor bending performance; high moisture capacity due to open capillary pores, which sharply increases thermal conductivity in a humid environment, which forces surfaces to be protected from moisture; Also, in the event of a fire, when heated above 600 degrees, aerated concrete releases toxic substances that are hazardous to health. The need to carry out long-term autoclave processing increases the cost of production. The complexity of manufacturing reinforced beams and floor slabs makes it difficult to master this material in construction.
For the manufacture of foam concrete A liquid foaming agent is used, added to the cement-sand mortar to form air pores. This material has long been used in construction, both in the form of factory-made wall blocks, and in the form monolithic structures construction production, obtained by laying foam concrete mixture in removable or permanent formwork. This material, like aerated concrete, has a low volumetric weight (foam concrete with a density of 600 kg/m3 is most often used), combined with high heat and sound insulation characteristics (the thermal conductivity of foam concrete is the same as that of aerated concrete). The expansion of the use of this promising material is hampered by such disadvantages as: susceptibility to shrinkage deformations and a loose structure, which is easily destroyed, crumbling into small fragments under the influence of dynamic loads, which requires careful handling during transportation, installation in the design position, and operation of structures made from this material; instability of the structure and density of foam concrete due to the compression method of supplying air to the solution during its manufacture; open pores increase moisture capacity, which sharply worsens its heat-protective qualities in a humid environment; large shrinkage of foam concrete during the process of gaining strength and drying. If it is necessary to fasten attachments to walls made of foam concrete, problems will inevitably arise, since the loose structure of this material does not allow fixing the fastening elements, even when using special anchor bolts. They simply fall out of the walls, in addition, destroying the structure wall material. Poor bending performance makes it practically impossible to manufacture reinforced beams and floor slabs from foam concrete.
In the 90s, scientists from the Rostov State Construction University (Doctor of Technical Sciences Morgun L.V. and Candidate of Technical Sciences Morgun V.N.) invented and mastered a new unique building material - fiber foam concrete, which is based on cellular concrete dispersedly reinforced with polyamide fibers. After many years of research, this material was introduced into industrial production with unique qualities: when using special mixers, maintaining technology and selecting the components of the mixture, foam concrete is obtained with a stable density and uniform structure, high frost resistance, bending 2.5 times better than ordinary concrete.
Due to the low moisture capacity due to closed air pores at a design humidity of 8% (zone A), the thermal conductivity coefficient of fiber foam concrete with a density of 600 kg/m3 is only 0.1207 W/mK (gas and foam concrete 0.22), due to which the wall thickness is 300 mm is enough to meet the required heat transfer resistance for Rostov-on-Don. Thus, it turns out that a structure made of fiber-foam concrete, having a thickness of 30 cm, in terms of thermal conductivity is equal to a wall made of hollow bricks, 1.5 m thick. That is, fiber-foam concrete is an effective heat insulator and has a high vapor permeability, due to which it can ensure optimal parameters microclimate in rooms whose enclosing structures are made of this material. This allows you to reduce heating costs in winter and completely abandon the use of air conditioners in summer, as well as do without the device forced ventilation(which is necessary when using vapor-proof materials such as polystyrene foam, chipboard, etc.). All this makes it possible to significantly reduce operating costs.
Increased tensile strength and fracture toughness in combination with reduced shrinkage deformability allow the use of fiber foam concrete for the production of elements load-bearing structures, including those working in bending. That is, this material is not only heat-insulating, but also structural, providing structures made from it not only with high heat and sound insulation performance, but also sufficient bearing capacity, strength and rigidity, which sets it apart from most other materials.
Fiber foam concrete is environmentally friendly pure material, since it contains only water, cement, sand, fiberglass and foaming agent. Due to this composition, it is a non-flammable material, does not emit any harmful substances in the event of a fire, and is safe for people living in the house.
According to their own physical and mechanical properties fiber foam concrete is similar to wood. Products made from it are easy to saw and mill. Attachments are fastened using conventional anchors and self-tapping screws, without the use of any additional funds(which is a significant advantage compared to structures made of foam and aerated concrete, expanded polystyrene, and other materials).
Since fiber foam concrete is non-flammable material resistant to atmospheric influences, it is possible to refuse plastering or the use of any other types of cladding in order to protect its surface from destruction. That is, it is possible to exclude labor-intensive plastering processes from the technological cycle of construction work, which force one to take into account seasonality and other costs for protective wall cladding. Only decorative finishing will be enough.
It is these unique properties of fiber foam concrete that predetermined its successful use in construction as a universal building material that allows it to be used to construct all the main types of load-bearing and enclosing structures of buildings. In the Rostov region since 2000. The production of building products made from fiber foam concrete has been mastered and is successfully continuing, mainly wall and partition blocks, fillets and decorative facade elements.
Sarmat-tornado LLC has developed and introduced into industrial production unique mixers for the preparation of fiber foam concrete mixtures with guaranteed properties with a density from 200 to 1200 kg/m3. Based on these mixers, mobile complexes for use in construction environments and industrial stationary complexes with full automation of the production process have been developed and implemented. Thanks to these developments, our Architectural and Engineering Firm LLC has been designing and implementing this for many years unique material and, together with the manufacturer, carries out further development of the methodology and technology for manufacturing various construction products.
The main methods of construction using fiber foam concrete:
1. Monolithic construction of buildings in removable and permanent formwork.
With this method, special forms are installed directly on the construction site - formworks that follow the contours of the future structural element, for example, walls, ceilings, etc., into which reinforcement is installed according to the project and a fiber foam concrete mixture is laid from a special mixer. Hardening of the mixture occurs naturally, like ordinary concrete. After hardening of the fiber foam concrete, ready-made structural elements building. Formwork elements are either dismantled (when using demountable formwork) or become part of the structure (when using permanent formwork). This method is the most cost-effective and is widely used in construction. Buildings made of monolithic fiber foam concrete are structurally rigid, which is most important in seismic conditions and on subsiding soils. The weight of such buildings is significantly lower than similar ones made of brick and concrete, which allows saving on the foundation. In addition, the speed of construction increases significantly. Houses completely cast from monolithic fiber foam concrete have the lowest heat loss due to good thermal insulation properties material and the absence of “cold bridges” that inevitably arise during construction from reinforced concrete. The disadvantage is the influence of weather factors (frost in winter and extreme heat in summer) on the rate of hardening of fiber foam concrete and the quality of the resulting structures. To improve the quality and possibility of construction under adverse weather conditions, it is recommended to use thermal formwork developed and sold by Sarmat-Tornado LLC, which significantly reduces negative impact heat and cold. Monolithic method construction allows the construction of buildings with complex and curved layouts.
Construction of a residential building from monolithic fiber foam concrete using industrial collapsible formwork. The fiber foam concrete mixture is placed into the installed formwork using the FPB500MP mobile complex.
Finished walls of a house made of monolithic fiber foam concrete after dismantling the dismountable formwork.
Construction of a residential building from monolithic fiber foam concrete using permanent formwork from chip-cement slabs.
After the installation of the formwork is completed, the resulting structure will be filled with a fiber foam concrete mixture.
A finished house made of monolithic fiber foam concrete after finishing work (plastering and painting chip-cement slabs of permanent formwork).
2. Use of small-sized wall and partition blocks and hand-laid lintels for the construction of cottages and buildings up to 3 floors. The same blocks are used for self-supporting wall filling of multi-storey frame-monolithic and other buildings. This method is best mastered in construction practice, and many years of experience show the high efficiency of using fiber foam concrete products to reduce construction time and improve the thermal characteristics of buildings. The use of fiber-foam concrete reinforced lintels solved the problem of “cold bridges” over windows, which previously inevitably arose when using reinforced concrete for their manufacture. Thanks to the accuracy of the dimensions of the factory-made blocks, the costs and time for finishing work are significantly reduced - walls and partitions do not need to be leveled using drywall or plaster; putty on a vinyl mesh is sufficient for final finishing. Due to high frost resistance, external surfaces do not require protection from atmospheric factors, but to improve the architectural appearance of the building, brick cladding, decorative plastering, or ventilated facades can be used, which will not deteriorate the performance characteristics of the material and will further reduce heat loss. The use of decorative facade elements made of fiber foam concrete (rusts, cornices, rosettes, pilasters, sandriks, keystones, brackets, moldings, and other elements) allows you to diversify the architectural appearance of buildings, which are much lighter and more durable than traditional ones made of gypsum and gypsum concrete, and at the same time can be easily finished , which allows you to improve the appearance of the building at the lowest cost. Due to the fact that fiber foam concrete holds screw anchors and screws well, there are no problems with fastening cladding and decorative façade elements.
Scheme of construction of a building from
fipropene concrete structural elements factory-made (wall blocks, lintels, floor slabs and coverings)
Construction of a residential building using prefabricated fiber-foam concrete structural elements (wall blocks and lintels)
Project of three-story residential buildings in the city of Belaya Kalitva, with enclosing structures made of fiber foam concrete wall blocks with brick lining.
Implementation of a project of three-story residential buildings in Belaya Kalitva.
Fragment of the facade of a residential building in Belaya Kalitva.
Internal apartment partitions made of fiber foam concrete wall blocks and lintels.
3. Construction of buildings from large blocks and floor and roof slabs from fiber foam concrete - this method develops the fully prefabricated construction of buildings from high-quality factory-made products and allows the construction of all structural elements of the building from one material at high speed for both mass and individual construction. Buildings entirely constructed from fiber foam concrete have high consumer qualities - environmentally friendly, with good heat and sound insulation. The walls are made of large blocks of three or four rows cut. Floors and coverings are made of reinforced fiber foam concrete slabs. Made from the same slabs pitched roof. In this case, the slabs are laid with the required slope, replacing rafter structures, and eliminating the need for complex thermal and waterproofing. Currently, specialists from Architectural and Engineering Firm LLC, together with Sarmat-Tornado LLC, have developed, successfully tested and patented a prefabricated fiber foam concrete floor slab and are preparing its industrial production.
5. Construction of monolithic reinforced concrete buildings of any number of storeys using permanent formwork made of fiber-foam concrete is a promising method of constructing frame-monolithic buildings, in which permanent formwork of columns, walls, beams and ceilings is installed from factory-made fiber-foam concrete elements into which they are installed reinforcement cages, and a mixture of heavy concrete is laid. This method of construction makes it possible to speed up construction - there is no need to wait for the concrete to gain strength, or to remove and remount the formwork. There are no cold bridges in buildings and the acoustic characteristics are significantly improved.
Scheme for the construction of a frame-monolithic building using permanent formwork made of fiber foam concrete.
Section of a building using permanent formwork made of fiber foam concrete.
6. Very promising direction is use of fiber foam concrete in the construction of energy efficient and passive buildings. When converting houses built from traditional building materials to energy-efficient and passive technologies Substantial part costs are spent on insulation and elimination of “cold bridges” to achieve the required thermal conductivity coefficient from 6 to 10 W/mK. Without all these measures, such technologies do not work. In buildings constructed entirely of fiber foam concrete, the required thermal conductivity can be achieved without any additional measures or costs, which makes the implementation of such technologies more economically attractive.
Fiber foam concrete: more expensive - yes, but is it better?
Increased requirements for the thermal characteristics of external walls and roofs of residential buildings, caused by the requirements for energy efficiency of buildings under construction and reconstruction, predetermined the appearance on the market of a wide range of thermal insulation materials.
Fiber foam concrete is one of the lightweight concretes.
The scope of thermal insulation is very diverse. Slab insulation is used for effective brickwork, as well as when installing roofs, they are sheathed brick walls, after which ventilated facades are made. Large blocks of lightweight concrete are used for the construction of self-supporting walls with floor-by-floor cutting in multi-story buildings residential buildings and for laying external walls during the construction of low-rise manor-type housing. In the market niche of lightweight concrete blocks there are now a lot of the most different offers, and here we offer both well-known aerated concrete and polystyrene concrete blocks, as well as relatively new ones - foam concrete, as well as the latest developments - fiber foam concrete blocks.
Comparison of some physical and mechanical characteristics of lightweight concrete.
Fiber foam concrete is foam concrete reinforced with randomly located pieces of synthetic or natural fiber (fibers) about 50 mm long. About fiber foam concrete and blocks made from it they say that this material is both structural and thermal insulating and has high strength. To check the validity of these statements, you should look at physical and mechanical characteristics this type lightweight concrete and compare with other types of similar materials.
The correctness of this comparison, of course, leaves much to be desired, since the characteristics of lightweight concrete are very dependent on their composition, and the compositions may vary depending on the preparation technology and chemical composition certain ingredients. However, by analyzing the data in this table, certain conclusions can be drawn. Thus, fiber foam concrete has the minimum thermal conductivity among all the materials under consideration, as well as foam concrete, which allows us to speak about the high thermal insulation properties of this material. The compressive strength of fiber foam concrete is slightly higher than the original foam concrete and is quite comparable with this parameter of other lightweight concrete. From the data presented, we can conclude that the characteristics of all non-autoclaved lightweight concretes are approximately identical, so it is difficult to talk about noticeable advantages of one of them. Price indicators also largely depend on the preparation technology, composition and other variable values.
What does dispersed reinforcement provide?
However, let's return to fiber foam concrete. Of course, adding fibers to foam concrete will not be able to change either the density or thermal conductivity of this material; this can only affect the strength indicators and operational characteristics. One of the main disadvantages of foam concrete is its high fragility, which leads to cracks and chips in the blocks when working with them. In addition, non-autoclaved foam concrete is characterized by high shrinkage deformations, which leads to products with cracks or even destruction. The introduction of non-metallic mineral or polymer fibers into the composition of cellular concrete makes it possible to eliminate or at least minimize these negative qualities. But whether dispersed reinforcement increases the strength of cellular concrete and, if it does, then by how much, is a controversial issue. Thus, from the materials that provide a link to the research of the RGSU (Rostov-on-Don) (http://www.btc-mos.ru/index.php?id_article=165) it follows that when polymer fiber fiber is included in the composition of foam concrete in the amount of 1 kg per 1 sq.m., its compressive strength does not increase. Moreover, increasing the amount of fiber to 3 kg per 1 sq.m generally reduces the strength by 10%. At the same time, research data from St. Petersburg State University of Civil Engineering (LISI) (http://fibron.ru/articles.html?id=6) says that the introduction of synthetic fibers into foam concrete can increase compressive strength up to 1.5 times. Both studies confirm that fiber reinforcement significantly increases flexural strength: SPbGASU speaks of 200 - 250%, and RGSU speaks of an increase in strength by 95% with a fiber content of 1 kg per 1 m2 and an increase in this indicator by 60% for every 1 kg increase in fiber quantity. In addition to the strength characteristics, studies by St. Petersburg State University of Civil Engineering record an increase of 7–9 times in the impact resistance of fiber foam concrete, as well as a sharp (up to 75–100 cycles) increase in frost resistance due to the ordering of the pore structure in the material. The almost complete disappearance of shrinkage cracks is also recorded, both at the manufacturing stage and during operation. At the same time, fiber foam concrete retains all real positive properties foam concrete: high thermal performance; soundproofing ability; resistance to rot, mold, fungi and rodents; environmental cleanliness; non-flammability; the ability to perceive temperatures up to +400 0 C. But for some reason, nowhere is it said that all the positive indicators of fiber foam concrete are extremely dependent on the technology for producing the concrete mixture. After all, if a relatively uniform distribution of fibers throughout the volume of the batch is not ensured, then the result will be simple foam concrete that does not have increased strength. In this respect, fiber foam concrete is similar to polystyrene concrete, for which it is also very important that foamed polystyrene granules do not accumulate at one point, but are placed throughout the entire volume.
Where to use fiber foam concrete?
Now about the specific use of fiber foam concrete. Its qualities, characteristic of this particular material, give maximum effect when used as:
thermal insulation of pipelines of process liquids and hot water, where its low weight, increased strength and absence of cracks will allow it to compete with traditional materials;
fire protection of steel and reinforced concrete structures, allowing you to achieve the required fire resistance of load-bearing columns and beams;
special anti-ricochet finishing of buildings and structures for military purposes.
The use of fiber foam concrete for monolithic or block walls in low-rise manor-type houses, self-supporting walls cut by floor for multi-storey construction is possible, but should be used when economic efficiency use of such material. The same can be said about the use of fiber foam concrete for the manufacture of thermal insulation slabs, tongue-and-groove partition slabs, etc. In these cases, the parameters of fiber foam concrete do not give it any tangible advantages over other types of lightweight concrete. As for the manufacture of floor slabs and lintels from fiber foam concrete, it is doubtful that for certain spans they will not require traditional reinforcement.