Road stone covered with fiberglass pros and cons. Composite reinforcement - pros and cons

Which appeared on the construction market relatively recently, has both advantages and disadvantages, which the consumer must be aware of. Despite the assurances of manufacturers that these products are a full-fledged replacement for metal fittings, their use can not be considered justified in all situations.

What is fiberglass reinforcement

The so-called composite reinforcement is a fiberglass rod around which a carbon fiber thread is wound, which serves not only to reinforce the structure of such a product, but also to ensure its reliable adhesion to the concrete solution. This type of reinforcement has both pros and cons, and its use should be approached very carefully.

Plastic clamps serve as elements for fixing carbon-fiber reinforcing bars to each other. It is convenient that the use of welding is not required to connect the elements of such fittings, which is undoubtedly a big plus.

Assessing the feasibility of using fiberglass reinforcement, it is necessary to consider all the pros and cons of its use in individual situations. This approach will ensure the high efficiency of this material as a means of strengthening building structures for various purposes.

If you do not take into account the characteristics of fiberglass reinforcement and do not compare them with the parameters of similar products made of metal, you can cause serious damage to the future building structure or finishing elements. That is why, before proceeding with the selection of elements for reinforcing concrete structures, it is necessary to understand in which cases the use of certain products is more appropriate.

Main advantages

Among the advantages that distinguish carbon fiber reinforcement, it is worth highlighting the following.

• An important advantage of fiberglass reinforcement is its low specific gravity, which makes it possible to use it for reinforcing lightweight structures made of cellular concrete and some other building materials. This allows you to significantly reduce the weight of structures that are reinforced with it. Meanwhile, the weight of a conventional concrete structure when using fiberglass reinforcement will decrease slightly, since it construction material has an impressive mass.
• Low thermal conductivity is also one of the advantages of fiberglass reinforcement. When using such fittings in concrete structures cold bridges are not formed (which cannot be said about metal reinforcing elements), which significantly improves their thermal insulation parameters.
• The high flexibility of fiberglass reinforcement allows it to be shipped to the customer in coils, rather than cut into individual bars. Thanks to the compact form of packaging, it is much easier to transport such fittings, for which you can use the trunk of any car, and this greatly reduces the cost of delivering the material to the construction site. The use of reinforcing elements, which are shipped not in cut bars, but in coils, also makes it possible to reduce material costs by reducing the number of overlaps. This positively affects both the strength characteristics of the future concrete structure and its cost, which is especially important when performing construction work.
• Such an advantage of fiberglass reinforcement as its durability inside a concrete structure is considered quite controversial. Reinforcement made of metal, being in an isolated state, is also not exposed to negative influence external factors, which ensures the durability of its use.
• CFRP reinforcement is a dielectric material, which is an advantage of products made from this material. Electrically conductive metal reinforcement is more susceptible to corrosion, which negatively affects its durability.
• Compared to metal reinforcing elements, fiberglass products are not exposed to chemically active environments. This advantage of fiberglass reinforcement is especially important in cases of construction of buildings in winter time when various salt solutions are added to the concrete, accelerating the hardening process.
• Being a dielectric, carbon fiber fittings do not create radio interference inside the building, unlike metal bars. This advantage is important when there are many reinforcing elements in the concrete structure. Otherwise, the use of composite reinforcement will not become a minus, but it will not be so relevant.

Fiberglass reinforcement also has disadvantages, which potential consumers should also be aware of.

Main disadvantages

The disadvantages of fiberglass reinforcement are associated with its following characteristics.

• The disadvantages of fiberglass reinforcement include, in particular, the fact that it does not withstand exposure to high temperatures. At the same time, it is difficult to imagine a situation where a reinforcing cage inside concrete can be heated to a temperature of 200 degrees.
• A rather high cost is a conditional disadvantage, given the fact that fiberglass reinforcement of a smaller diameter can be used to reinforce concrete structures in comparison with metal products.
• CFRP reinforcement does not bend well. This disadvantage limits its use in the creation of reinforcing frames for concrete structures. Meanwhile, it is possible to make bent sections of the reinforcing cage from steel elements, and then build them up with fiberglass rods.
• Reinforcement made of fiberglass does not withstand fracture loads well, which is very critical for concrete structures. Accordingly, their reinforcing frame must successfully withstand such loads, which reinforcement made of composite materials cannot boast of.
• Unlike a metal reinforcing cage, fiberglass products have less rigidity. Because of this drawback, they do not tolerate vibration loads that occur when they are poured using a car mixer. When using this technique, the reinforcing cage is subjected to significant mechanical loads, which can cause its breakage and violation of the spatial position of its elements, therefore, rather high requirements are imposed on the rigidity of such concrete structures.

Considering the advantages and disadvantages of fiberglass reinforcement, it is difficult to say how much better or worse it is made of metal. In any case, the choice of this material should be approached very reasonably, using it to solve the problems for which it is really intended.

Fields of application of fiberglass reinforcement

Reinforcement made of composite materials, the laying rules of which are easy to learn from the corresponding videos, are used in both capital and private construction. Since capital construction is carried out by qualified specialists who are well acquainted with the nuances and disadvantages of using certain building materials, we will dwell on the features of using such material in the construction of private low-rise buildings.

• Reinforcement made of composite materials is successfully used to strengthen foundation structures the following types: tape, the height of which is greater than the depth of soil freezing, and slab. The use of carbon fiber reinforcement to strengthen foundations is advisable only in cases where the building is being built on good ground, where concrete bases will not be subjected to fracture loads that fiberglass elements may simply not withstand.
• With the help of fiberglass reinforcement, walls are strengthened, the laying of which is made of brick, gas silicate and other blocks. It should be noted that as a connecting element of walls, composite reinforcement is very popular among private developers, who use it not only to strengthen the masonry of load-bearing structures, but also to ensure their connection with facing partitions.
• This material is also actively used for bonding elements of multilayer panels. The structure of the latter includes a layer of insulation and concrete elements, which are interconnected using fiberglass reinforcement.
• Due to the fact that the reinforcement of this type is free from such a disadvantage as susceptibility to corrosion, it is often used to strengthen various hydraulic structures (for example, dams and basins).
• In cases where it is necessary to effectively increase the rigidity of glued wooden beams, they are also reinforced with fiberglass reinforcement.
• This material is also used in road construction: with its help, they strengthen the layer of the asphalt canvas, which is subjected to increased loads during its operation.

Summarizing all of the above, it should be noted that the use of fiberglass reinforcement can be quite effective, given its shortcomings and the limitations associated with them, which are specified by the manufacturer.

Can fiberglass reinforcement replace metal analogues

Despite the fact that reinforcement made from composite materials is a fairly new material in the construction market, you can already find many recommendations (and even videos) on its use. Considering these recommendations, we can conclude that it is best to use fiberglass reinforcement to strengthen walls erected from bricks and building blocks, as well as to connect load-bearing walls with interior partitions.

Every building needs a foundation. To make it stronger, reinforcement is inserted into the concrete. Previously, it was made exclusively of metal. Modern technologies allow the production of composite reinforcement. It has its pros and cons, and therefore, before using it in the construction of a bath, you should carefully study the features.

Material Features

Reinforcement, which is made from various composites, has found application both in private and in capital construction.

Composite reinforcement can be of two types depending on the material of manufacture. It is made from fiberglass or basalt fiber. The latter is much more expensive, although its properties slightly exceed the quality of fiberglass rods.

The peculiarity of composite reinforcement is that it consists of two layers - internal and external. Inner part- this is a core of fibers arranged in parallel. These fibers are interconnected by a composite of epoxy or polyester resins. It is from the core that the characteristics of the reinforcement depend.

Fibers are wound onto the core in the form of a spiral, which are also interconnected using a composite. This part is responsible for adhesion to the concrete solution.

Since the composite material does not have sufficient bending strength, it is not suitable for knitting when laying steel bars. To do this, it is better to use plastic clamps.

Advantages and disadvantages

The carbon fiber rods are fastened with special clamps; there is no need to use welding for fastening

The advantages of composite reinforcement include:

• light weight;
• the cost is lower than that of the metal;
• strength;
• resistance to aggressive environments;
• excellent heat-insulating properties, which is the main advantage in the construction of a bath;
• is not a conductor, and therefore does not interfere with radio waves;
• service life can be 80 years;
• fittings are sold in bays, and therefore the length of the rod is unlimited.

And yet, composite reinforcement also has disadvantages:

• it cannot be operated at temperatures above 200°C;
• not too tight. However, the last drawback is important only in the construction of high-rise buildings. In the foundation of the bath, elasticity does not play any role.

If you are not going to heat the foundation of the bath to too high temperatures, then the best choice is the use of composite reinforcement. Durable and lightweight material, which can be cut into pieces of any length, has excellent reinforcing properties.

Fiberglass reinforcement is a building material created on the basis of fibers bound by a complex composition. It is produced on the basis of basalt, glass and carbon fiber, and they can be combined. However, basalt-plastic reinforcement and fiberglass are considered the most popular.

What is it made from?

It consists of two parts. The first is the trunk, due to which the high strength of the material is achieved. The fibers are bonded together by the polyester resins of the composite. The outer layer serves for reliable adhesion to concrete: it is a fibrous body that is wound around the trunk in a spiral. It is thanks to this composition that plastic fittings received positive reviews as reliable material for construction. There are various variations of rebar models, and some of them are quite unusual. For the production of this building reinforcement, fiberglass is used. Its peculiarity is that there are practically no analogues in the world, and positive traits significantly expand the scope. In addition, this material is modern and efficient, and therefore perfectly meets the requirements of the construction process.

At the heart of any fiberglass reinforcement are two components. The first is the reinforcing material itself, the second is the binder (a mixture based on the ratio of these components is 75 to 25. In composite reinforcement, all mechanical loads fall on the reinforcing component, while the binding materials are a kind of matrix that evenly distributes load on the entire length of the rod and protects it from external influences.

The most common recipe can be considered as follows: glass roving or basalt fiber is used as a reinforcing link, epoxy resin, in addition, the composition of the material will include a hardener and an accelerator. However universal composition does not exist, since each manufacturer builds its own technological process.

What is the secret of popularity?

It must be said that compared to metal materials, plastic products are much more in demand today. Moreover, plastic fittings are used in any construction process. This is achieved through several qualities:

1. Resistance to corrosion, aggressive environment, including the alkaline environment of concrete. Unlike metal, plastic does not rust or break. These qualities contribute to the fact that plastic structures are widely used in the equipment of berths, protective structures at water bodies.
2. Reliability and strength, which is greater for plastic products than for steel ones. It is reliability that allows them to be used in the construction of building structures for various purposes and volumes.
3. High tensile strength.
4. The lightness of the reinforcement: for example, compared to the steel variety, the plastic one is five times smaller in weight and 11 times smaller in diameter. These figures indicate that you can save on construction work, as well as on the transportation of material to the object.
5. Low thermal conductivity, due to which cold does not penetrate into the premises. It is no coincidence that plastic reinforcement for the foundation is increasingly being used: during its construction, it is possible to achieve high energy efficiency due to economical materials.
6. Resistance to exposure to radio waves.
7. Possibilities of application in various temperature conditions: -70 to +100 degrees.
8. Costs: buying a linear meter of plastic fittings will be much cheaper compared to, for example, a one-meter segment of a metal bar.

Features of composite fiberglass

Composite fiberglass reinforcement appeared on the domestic market not so long ago and today is considered new technology. Such plastic reinforcement also received good reviews, since it has a number of advantages compared to metal counterparts. Firstly, such structures are lightweight, so there will not be too much load on the foundation, which means that the building will last much longer. Secondly, due to the high tensile strength, such reinforcement can be used for the construction of complex structures. design features objects. Thirdly, the composite material is resistant to aggressive environments and does not conduct electricity.

On the other hand, composite plastic reinforcement has a weaker elastic modulus compared to steel products. Elasticity is especially lost when the composite is heated to 600 degrees. But on the other hand, it is this characteristic that speaks in favor of the fact that plastic fittings have also found application for the installation of the foundation, where tensile strength is very important.

Where are composites needed?

1. In floor slabs: as a rule, reinforcement is placed in the upper or lower concrete zone, while the concrete class should be B25.
2. When reinforcing structures made of concrete and reinforced concrete.
3. When building foundations with zero mark occurrence.
4. In reinforced structures that are exposed to aggressive environments.
5. At repair work associated with damage to concrete due to exposure to aggressive environments.
6. For reinforcement brickwork, especially if it is performed in winter.

Where is fiberglass reinforcement used?

The scope of this building material is extensive:

1. Due to the tensile strength of fiberglass, it is advisable to use it for the construction of the base for objects. First, the installation will be simple. Secondly, the foundation will be strong. plastic fittings for the foundation, the reviews are positive due to the fact that it allows you to create a monolithic foundation. It is placed directly into the concrete solution during the pouring process, which makes the adhesion of materials stronger. In order not to form pores and cavities at the junction, specialists use special vibration equipment.
2. When equipping a power line high voltage. Since the material does not conduct current, energy will be lost to a minimum, while its operation will be safe.
3. Plastic reinforcement reviews builders receive positive due to its versatility. Yes, it can be used to increase strength. roadbed, pillars, bridges.
4. Composite materials form the basis for the production of sleepers. Due to the intense vibration that causes concrete to break down, it was necessary new material, and fiberglass reinforcement has become the right and effective solution.
5. The metal is not resistant to aggressive environments, high humidity, solvents and acids, respectively, its service life is not very long. Fiberglass used in the construction of docks, berths, various barriers on coastline, shows the best performance.
6. Plastic reinforcement is also used in mine equipment when fixing a special mesh that protects the walls and vaults of the mine from collapse and fixes them.
7. You can not do without this material and when fixing the insulation or facing material on the finished wall.

Varieties of fiberglass reinforcement

Plastic reinforcement in construction today is used more and more often, which is associated with its unique characteristics. In addition, composite reinforcement today means whole line non-metallic structures, which significantly expand the scope of their application. So, modern manufacturers offer fiberglass and basalt rebar. At the same time, a variety of substances can act as polymer resins that bind the fibers, each of which has its own characteristics.

Any building material is used on the basis of certain rules and requirements. This also applies to composite reinforcement. Plastic fittings, the characteristics of which are so diverse, are used in construction on the basis of SNiP, approved back in 2003. By the way, each type of material is controlled by the manufacturer, and therefore the fittings must necessarily correspond to the parameters that were originally declared.

Reinforcement for the foundation: how to choose?

Today, in private housing construction, plastic reinforcement for the foundation is increasingly used. Experts advise when choosing it to contact official dealers and reliable manufacturers, since the strength and durability of the building as a whole will depend on the quality of the material. An important role is played by the quality of the product, as well as the density of the winding of glass roving along the entire length of the rod. The coils must also be filled with high quality. materials good quality- this is the most optimal choice for the equipment of any foundation - slab, tape or columnar. The type should be chosen depending on the bearing capacity of the soil, as well as the load on the building as a whole.

Reinforcement of the foundation is necessary in order to make the load on the foundation of the building more uniform during operation. Concrete has compressive strength, but its structural integrity can be compromised by stress. It is with the help of reinforcement that greater adhesion to concrete is achieved, respectively, the foundation becomes stronger and more reliable. The main requirements when choosing fittings should be the following:

• providing rigid adhesion to concrete;
• durability;
• flexibility;
• rust and corrosion resistance.

The fittings can be working, that is, reducing stress and external loads, as well as distributive, when the load is evenly distributed on each rod - this contributes to the preservation correct location working rods. With the help of clamps, the rods are connected into a frame, protecting the concrete from cracking. Transverse rods protect against the occurrence of inclined cracks in the foundation, and longitudinal - from vertical ones.

slab foundation

When erecting this type of base, reinforcement with a ribbed surface with a diameter of at least 10 mm is needed. It is the diameter that affects how strong the reinforcement will be. Plastic reinforcement for the foundation, reviews of which are so good, should be selected depending on the type of soil. Suppose, on non-porous and dense, that is, with good bearing capacity and resistance to deformation, the thickness and diameter can be small. If the house is massive, but on soft ground, the reinforcement should be thicker - about 14-16 mm. With this option, the reinforcement of the slab will be upper and lower, and the total number of bars will be more than 100. Knitting can be done in several ways. For example, first reinforcement bars in the lower chord can be connected longitudinally and transversely, then vertical bars are attached to them, then again transversely and longitudinally. When knitting fiberglass reinforcement, it makes sense to use clamps and plastic ties. This is the so-called binding of reinforcement with plastic clamps.

Strip foundation

As a rule, the tape base has a height greater than the width. Accordingly, the tape due to small size it is prone to bending, and therefore, when building such a foundation, reinforcement with a smaller diameter can be used. The peculiarity of this base is that two reinforcement belts will be needed, regardless of what its height will be. The process of laying the reinforcement will be as follows: rods are laid longitudinally in the upper and lower parts of the foundation at a distance of up to 5 cm from the concrete surface - it is they who will bear the entire load in case of deformation. Reinforcement in several bars can be used for weak or moving soil, as well as for the construction of oversized houses. Ideal for building strip foundation fiberglass fittings - grades f6 and f7 (for houses on one floor), grades f8 and f10 - for residential buildings with an attic or two floors.

Column Foundation

Good plastic fittings (reviews confirm this) and during the construction of this structure. When reinforcing the columns, metal reinforcement with a diameter of 10 mm or fiberglass f6 is useful. As vertical bars, it is better to choose reinforcement with a ribbed surface, and horizontal ones are needed only for tying the bars into a single frame. The reinforcing cage is 2-4 bars as long as the height of the post. For example, when reinforcing a pillar 2 meters high and 20 cm in diameter, four f6 bars will be needed. They need to be placed 10 cm apart, and also tied up with smooth fittings with a diameter of f4 or f5. For any type of foundation, fittings for plastic pipes will also be required.

Features of knitting reinforcement

The foundation is an important component of any building, its quality and reliability are the guarantee that it will stand for a long time and serve reliably. The reinforcement of the base must be approached wisely. Consider how plastic reinforcement is knitted for a strip foundation, since it is it that is used most often in private housing construction. Knitting is needed in order to make the design of the reinforcing cage uniform and more durable. The rods are connected in those places where they intersect. A piece of wire is bent in the middle, then it is put on a special hook, which is applied to the reinforcement and tightened. An easier knitting method involves the use of plastic ties.

When creating a reinforcing system, plastic valves are important. Its main function is to contribute to a more durable and reliable fastening of plastic rods to each other. The most popular details in this regard are clamps, which are special and contribute to the creation of a protective layer with a certain thickness in concrete. The plastic rebar retainer is created by injection molding from polyethylene under high pressure. They are needed in order to securely fix reinforcing bars, frames in space, which will provide a protective layer in concrete or reinforced concrete structure. Clamps can be designed for horizontal and vertical surfaces, as well as for creating formwork.

How is plastic reinforcement made?

When you decide to build your home, pay attention to a lot of little things and start by building a foundation. Many are interested in the question of where to buy plastic fittings. Experts advise contacting trusted companies, since the durability of the service of the structure itself depends on the foundation of the house, its quality and reliability. Equipment for the production of fittings is quite expensive, and the quality of materials depends on its quality.

Plastic fittings, the production of which is carried out on high-tech equipment, can be produced in different diameters - 4-24 mm. Depending on the type of line, a different number of bars will be produced, as well as different sections. As a rule, the scope of delivery includes a number of devices - from a thread heating device and an impregnation bath to a broaching device and a control cabinet. Thus, the equipment for plastic fittings should be chosen correctly in order to make the technological process efficient.

Plastic fittings: customer reviews

In their reviews, builders - experienced and not very experienced - agree on one thing: plastic fittings are just perfect for installing the foundation. For example, some have used a combination of steel and plastic rods: the foundation slabs and basement walls are made from plastic, while the floors, where stronger materials are needed, are built from steel. Many also note the convenience of knitting compared to metal reinforcement, which is supplied in one rod. In terms of tensile strength and resistance to decay, there is also no better plastic reinforcement.

But, on the other hand, it does not do without negative reviews. True, judging by them, these shortcomings are still more than offset by advantages. For example, there is an opinion that hands itch after working with fiberglass. In addition, it is almost impossible to bend it to make, for example, corners in the form of the letters L or P. At the same time, the manufacturers themselves focus on the fact that fiberglass reinforcement should be used exclusively for the installation of the foundation.

Steel or plastic: what to choose

For a beginner in construction, the choice of materials is always an important issue. For example, when making a foundation, it is important to perform competent knitting of reinforcement. Of course, in the case of building a bath, you can use simple metal rods, but what to choose for a solid home? Today there is a choice between steel and plastic structures, each of which has its own distinctive features and disadvantages. If we talk about the merits, then they can be reduced to the following points:

As you can see, the advantages of the plastic variety are still greater. The disadvantages of steel include: the occurrence of corrosion and the large weight of the structure, while plastic fittings are only difficult in terms of bending. Thus, according to their technical specifications fiberglass reinforcement is in no way inferior to steel, while it costs less. On the other hand, it is very important to remember about the features of the construction of a particular house. For example, if you need to connect the facing material and the wall, then you can use plastic-based fittings. But when equipping concrete floors with reinforcement, it is better to use metal constructions, because in view of heavy weight they will not float when pouring concrete. Thus, when choosing structures for reinforcement, several factors should be taken into account at once, which means that it is better to use professional help specialists.

The main advantages of composite reinforcement are its low weight, high tensile strength, high chemical and corrosion resistance, low thermal conductivity, low thermal expansion coefficient and the fact that it is a dielectric. High tensile strength, which is much higher than that of steel reinforcement with equal diameter, allows the use of composite reinforcement of a smaller diameter instead of steel.

You can’t even imagine how beneficial the use of fiberglass reinforcement is! The economic gain from its use is made up of a number of factors, and by no means just the difference in cost between a running meter of steel and composite reinforcement.

Don't hesitate to look Full description factors that make up your savings Money, time, man-hours, electricity, Supplies etc. in the article "SAVINGS FROM THE USE OF COMPOSITE REINFORCEMENTS"

But, it must be remembered that composite reinforcement has significant disadvantages. Majority Russian manufacturers do not advertise these disadvantages, although any civil engineer can notice them on their own. The main disadvantages of any composite reinforcement are the following:

• the modulus of elasticity of composite reinforcement is almost 4 times lower than that of steel reinforcement even with the same diameter (in other words, it bends easily). For this reason, it can be used in foundations, road slabs, etc., but the use in ceilings requires additional calculations;
• when heated to a temperature of 600 ° C, the compound that binds the fibers of the reinforcement softens so much that the reinforcement completely loses its elasticity. To increase the resistance of the structure to fire in the event of a fire, it is required to take additional measures for the thermal protection of structures in which composite reinforcement is used;
• composite reinforcement, unlike steel, cannot be welded by electric welding. The solution is to install steel tubes (at the factory) at the ends of the reinforcing bars, to which it will already be possible to apply electric welding;
• such reinforcement cannot be bent directly on the construction site. The solution is to manufacture reinforcing bars of the required shape at the factory according to the customer's drawings;

Summarize

Despite the fact that all types of composite reinforcement are a fairly new material on the Russian construction market. Its application has great prospects. To date, it can be safely used in low-rise construction, in foundations various types, in road slabs and other similar structures. However, for its use in multi-storey construction, in bridge structures, etc. — it is required to take into account its physical and chemical features even at the stage of preparation for designing.

A curious fact - reinforcement in coils!

The main application of reinforcement in low-rise construction is its use for reinforcing foundations. At the same time, steel reinforcement of class A3, with diameters of 8, 10, 12 mm, is most often used. The weight of 1000 linear meters of steel reinforcement is 400 kg for Ø8mm, 620 kg for Ø10mm, 890 kg for Ø12mm. Theoretically, you can purchase steel reinforcement in coils (if you find it), while, later, you will need special device to re-align such reinforcement. Will you be able to transport 1000 meters of such rebar in your car to the construction site in order to reduce shipping costs? Now imagine that the indicated reinforcement can be replaced with a composite one of a smaller diameter, namely 4, 6, 8 mm instead of 8, 10, 12 mm. respectively. The weight of 1000 linear meters of composite reinforcement is 20 kg for Ø4mm, 36 kg for Ø6mm, 80 kg for Ø8mm. In addition, its volume has slightly decreased. Such fittings can be purchased in bays, while, external diameter the bay is slightly more than 1m. In addition, when unwinding such a coil, composite reinforcement does not require straightening, since it has practically no residual deformation. Could you imagine that you could transport the fittings required for the construction country house or cottages, in the trunk of your own car? And you don't even need help with loading and unloading!

Reinforced concrete structures are traditionally reinforced with a metal bar, but an alternative option, fiberglass reinforcement, is becoming increasingly popular. It replaces steel due to its high performance and technical characteristics. The growing popularity of plastic fittings is explained by low price compared to metal counterparts.

Description

The production and characteristics of the so-called composite reinforcement for concrete monoliths and structures are regulated by GOST 31938-2012 developed according to ISO 10406-1:2008. A high-strength carbon thread is wound on a specially prepared fiberglass base. It improves adhesion to concrete due to its helical profile.

The main element of the composite fiberglass reinforcement is the trunk, made of strong, parallel to each other fibers, united by a polymer resin sintered at high temperature. The barrel is covered with a fibrous structure applied by spraying or winding in two directions.

According to SNiP 52-01-2003, the use of modern fiberglass reinforcement is possible as a full-fledged replacement for metal reinforcement. Each manufacturer specifies specifications on its products, which can be used in walls, ceilings, basements and other concrete structures. It is mandatory to provide quality certificates based on examinations and test reports in laboratories.

Kinds

Fiberglass reinforcement is classified according to the types of materials used in the production. This is a non-metallic raw material of mineral or artificial origin. Industry offers the following types:

• Glass composite (ASP) - is a heat-treated mixture of longitudinally arranged fiberglass and polymer resins.
• Basalt reinforcement or basalt composite (ABP) - is made from basalt fibers interconnected by organic resins.
• Carbon-fiber or carbon-composite rebar (AUK) - has increased strength and is made from hydrocarbon compounds. It is more expensive than composite.
• Aramidocomposite (AAC) - based on polyamide fibers like nylon threads.
• Combined composite (ACC) - at the base is a fiberglass rod, on which basalt plastic is tightly wound. This type is not basalt rebar, which is confused with it, as it has a fiberglass core.

Manufacturers offer a large selection of fiberglass reinforcement in thickness. This makes it possible to make both a thin mesh of 4 mm and a strong reinforcing frame with a diameter of 32 mm for load-bearing structures. It is supplied in the form of cut whips or coils up to 100 m long.

This material is available in two types of profile:

• Conditionally smooth. Made from the main rod with a layer of quartz sand sprayed with a fine fraction, which improves adhesion with the concrete mix;
• Periodic. It is made of a rod, on which a fiberglass bundle is tightly wound, as a result of which anchor ribs appear on the rod, reliably holding it in the thickness of concrete.

Advantages and disadvantages

Fiberglass reinforcement is a new building material that is gaining popularity, has characteristics that allow it to be used for load-bearing structures. Its advantages include:

• Corrosion resistance. Fiberglass can be used aggressive environments. According to this indicator, this material is 10 times superior to metal.
• Low thermal conductivity of 0.35 W/m∙⁰С, which makes it possible to increase the thermal insulation of the concrete monolith, eliminates the risk of cold bridges. For comparison, the thermal conductivity of steel is 46 W / m∙⁰С.
• High resistivity allows it to be used in the construction of bridges, railway structures, power lines and other structures where there is a risk of penetration electric shock under high voltage.
• Low specific gravity, which reduces the pressure of structures on the surface of the soil, foundation. The average density of this material is 1.9 kg / m³, while steel has four times more - 7.9 kg / m³.
• The cost of fiberglass reinforcement is almost 2 times lower than with a metal bar.
• Application in a wide temperature range. It does not lose its properties at temperatures from -60 to +90⁰С.
• Unlike metal, fiberglass has a coefficient of thermal expansion similar to concrete, so a monolith with such reinforcement does not crack with temperature changes.
• For the installation of a reinforcing mesh, you do not need a welding machine, it is enough to connect it with plastic bundles and clamps.

Like any material polymer reinforcement based on fiberglass has disadvantages that are taken into account during operation:

• Insufficient resistance of fiberglass to high temperatures, the resins used to bind the fibers ignite at a temperature of 200⁰С. For private houses or utility rooms, this is not a problem, but at an industrial facility, where the concrete monolith must be refractory, the use of this reinforcement is unacceptable.

• Almost 4 times lower elasticity modulus compared to steel.
• When preparing the mesh, it is almost impossible to bend the composite at the desired angle, due to the low fracture strength, such elements have to be ordered at the factory.
• One of the disadvantages of fiberglass composite reinforcement is that it does not allow making rigid reinforcement, and its strength decreases slightly over time.

Characteristics

Composite reinforcement is evaluated according to technical parameters. This material has a relatively low density. Therefore, the weight running meter fiberglass reinforcement, depending on the diameter - from 20 to 420 g.

Plastic reinforcement has a constant winding pitch - 15 mm. This is the optimal value for minimum cost material, provide high level adhesion to concrete.

Technical characteristics of fiberglass reinforcement are summarized in the table:

Features of production and installation

Any type of fiberglass reinforcement is made from raw fiber bound by polymer resins, to which a hardener and a hardening accelerator are added. All components are determined by manufacturers depending on the technologies used, on the type and purpose of the elements that will be reinforced with the manufactured fiberglass reinforcement.

The material is produced on special technological lines. First, the fiberglass is impregnated with resin, a hardener and a reaction accelerator. After that, it is passed through a spinneret, where excess resin is squeezed out. Immediately, the fiberglass is compacted and takes on a shape - conditionally smooth or with anchor ribs and a technologically specified diameter.

At the next stage, the composite fiberglass reinforcement is knitted - an additional winding in the form of a bundle is wound on it in order to increase adhesion. After that, it is sent to the oven, where the polymer resins with the hardener are set. The resulting products are stacked in bays or cut into whips of the desired length.

The bars are fastened with plastic clamps or clamps. The edge of the reinforcing mesh should recede from the formwork by 50 mm, which will create a protective layer of concrete. This is done with improvised means or plastic clips. If the rod protrudes beyond the formwork, it must be cut with a hacksaw or grinder with a diamond or abrasive wheel.

It is impossible to bend fiberglass reinforcement on site without special equipment. After the force ceases to act on the rod, it again returns to its original shape. If you soften it with temperature, and still bend it, it will lose its design characteristics. The only way out is to order a pre-curved fiberglass element at the factory, in which case they will fully meet the technical and operational requirements.

Conclusion

Composite reinforcement may well replace the traditional metal structure. It is superior to steel reinforcement in many ways. It is used in the construction of walls, foundations and other structural elements from blocks and bricks, it is increasingly used to reinforce solid concrete monoliths.

The use of fiberglass composite reinforcement significantly reduces the mass of structural elements, which allows additional savings on the foundation. The limitations of the use of this material include fire safety requirements at individual industrial enterprises, in other cases it is the best alternative to metal.