Technological features of the manufacture of fiberglass reinforcement. Equipment for the production of fiberglass reinforcement Manufacturing of fiberglass reinforcement

On modern construction sites, a wide variety of objects, structures and structures can be seen more and more often instead of metal fittings. An alternative reinforcing material made of composite raises many questions: consumers are interested in the composition of the rods, application features, characteristics and, of course, the production technology of fiberglass reinforcement.

The main component of the production of composite rods is roving - a special fiber made from molten glass with a thickness of 10-20 microns. Special resins are used to join together a large number of fiberglass into a strong rod. In addition, acetone, dicyandiamide and ethyl alcohol are also involved in the technological process of manufacturing fiberglass reinforcement. If rods are made with a spiral winding, then fiber is also required for winding.

Composite Rod Production Line

It should be noted that the process of manufacturing fiberglass reinforcement today refers to high-tech, carried out on a fully automated production line with minimal human participation. The line with continuous broaching is served by an operator who controls the process, and at the same time, the manufacture of valves can be carried out around the clock.

In the technology of producing composite reinforcement, everything starts with a mechanism - a creel that simultaneously feeds about 60 glass threads into the tensioning mechanism.
After equalizing the stress of all fibers, the threads are arranged in the required order and are connected into one thread.
Then the threads go through a heat treatment stage, where excess moisture, oil, dust and other contaminants are removed from the fibers.
The next stage in the technology of manufacturing rods is the immersion of fibers in a bath with heated binders.
Fibers impregnated with resins are pulled through a mechanism that forms the diameter of the future rod. If a rod with a winding is produced, then a spiral winding of the fiber follows.
In the next oven, the resins that bind the fibers undergo a polymerization process.
At the next stage, the bar is cooled and finally either fed for coiling into coils on a special device or cut into pieces of standard length.

Fiberglass rebar is a building material made from glass roving, bonded with an epoxy compound based on thermosetting resins. The main feature is lightness, the indicator of mass per unit volume is only 2g / mm³. Working with fiberglass reinforcement is more convenient and economically feasible than with metal reinforcement. Significantly less costs are required for logistics and directly for reinforcement.

In addition, due to the fact that fiberglass does not react to an aggressive environment, the reinforcement protects the concrete from premature destruction, thereby increasing the service life of the object. Fiberglass reinforcement reacts to temperature changes similarly to concrete, which also has a good effect on the strength of the structure.

The strength of fiberglass in comparison with metal is 2.5 times higher. With all this, the thermal conductivity index is 100 times lower than the thermal conductivity index of steel. Therefore, the structure, which is reinforced with fiberglass, does not freeze (does not form "cold bridges") and an object built using fiberglass will be warmer than a building based on metal reinforcement. This allows you to reduce heating costs, and therefore the material is actively used in the construction of modern energy-efficient buildings.

Also, the indisputable advantages that may interest builders are the fact that fiberglass is an amazingly durable material, which does without additional repair work for 100 years after installation. This is what fiberglass reinforcement for the foundation is famous for.

Fiberglass fittings have found their application in many areas of industry, construction, utilities:

in construction, it is used in the construction of civil and industrial construction as a basis for foundations, floors, crossbars, as well as in the construction of earthquake-resistant belts;
in the construction and repair of roads, reinforcement is used in the arrangement of embankments, road beds, in the construction of bridges and highway barriers. It is resistant to the effects of reagents that are applied to road surfaces (for example, anti-icing reagents), therefore it can be used both in Moscow and in colder regions.

Fiberglass reinforcement will be the ideal base for concrete and brick structures. It is used in the creation of supports for power lines and lighting, in the construction of road, sidewalk and fence plates, as well as in the construction of sleepers on railway tracks. Reinforcement for floors, where reinforcement mesh is used, is widely used, even together with metal.

Fiberglass is applicable in such building structures as monolithic foundations and foam concrete. It is also actively used in the creation of structures that must have increased resistance to the effects of chemicals, for example:

during the construction of storage facilities for chemical waste and components;
when arranging sewerage, water supply systems, land reclamation systems;
in the construction of port facilities and in the strengthening of coastlines.

Despite the uniqueness of the product, fiberglass reinforcement, the price in Moscow for which is indicated on our website, is an affordable material for both construction organizations and individuals. Its cost is 40-50% lower than the cost of steel reinforcement, which can significantly reduce costs and at the same time improve the quality of the facilities being built. In general, composite rebar can be called one of the most reliable and efficient building materials of our time.

This reinforcement is made of straight strands of glass or basalt fibers (respectively ASP and ABP), which are collected in a bundle, impregnated with a thermosetting polymer binder, molded, heated (polymerized) and cooled. As a result, a monolithic rod of high strength is obtained, according to the test results it is 3 times higher than the tensile strength of steel, and the weight, in an equal strength ratio, is 9 times less.

As a standard, it is manufactured in the form of rods of any length, at the request of the customer. With a diameter of up to 8 mm inclusive, it can be made in the form of coils (coils) containing 100 meters of reinforcement. Overall dimensions of the bay: height - up to 8 cm, diameter - up to 1 meter.

form of issue

With a diameter of 10 mm and 12 mm, it can be made in the form of coils (coil fittings) with a length of 50 meters. Overall dimensions of the bay: height - up to 5 cm, diameter - up to 1.5 meters.

By agreement with the customer, it is possible to manufacture rods and coils of any length.
It can be made with a smooth, building, periodic profile:

ASP-ABP of periodic profile, used instead of steel reinforcement of class A-III (A-400);
ASP-ABP smooth profile, used instead of steel reinforcement class A-I (A-240).

Fiberglass reinforcement is becoming more and more popular and its use is becoming more and more relevant every year, because it is a full-fledged replacement for traditional rods made of steel of different grades. High strength indicators, optimal performance properties, low specific gravity and low price are the factors that determine the popularity of the use of non-metallic reinforcing elements in all areas of construction.

Fiberglass reinforcement

Modern technologies have made it possible to create non-metallic composite reinforcement, which favorably differs from the traditional one by the combination of increased strength, chemical and corrosion resistance and low cost.
Technological line, "TLCA-2" designed for the manufacture of composite reinforcement made of glass roving and basalt roving, used as a reinforcing element for construction work. Differs in ease of installation, speed of production of valves. service staff 3 people. The lines are in stock, installation supervision and training are included in the price.
The equipment of our production is distinguished by simplicity, ease of maintenance and productivity, while the price of the equipment is lower than that of other manufacturers.
For example: equipment in China costs 3,000,000 rubles, while the production rate is two times lower than ours. The cost of the English equipment is 8,000,000 rubles. In the Russian Federation, prices for technological lines for the production of valves start at 2,000,000 rubles, or even higher.
The specialists of our company are constantly working to improve the equipment, while practically not increasing its cost. The supplies of our equipment have a wide geography, this includes cities such as Nizhny Novgorod, Kazan, Orenburg, St. Petersburg, Magnitogorsk, Krasnodar, Yakutsk, Yekaterinburg, Tolyatti, Cheboksary, Krasnodar, Stavropol, Kaliningrad, Orenburg, Tyumen, Chelyabinsk, Irkutsk, Ufa, Samara, Ulyanovsk, Moscow, Lipetsk, Belgorod, Rostov-on-Don, Simferopol, Neftekamsk.

Basic properties of the TLCA-2 line:

productivity 5-10 km per shift 8-10 hours
diameter from 4 to 20 mm, the larger the diameter of the reinforcement, the lower the production speed, but the greater the profitability of the product
the length of the line is 18 m + the length of the fiberglass rod is up to 6-12 m, the workshop is needed about 25 m long, the width of the line is 2 meters.
Profitability 100% .- 120%
the number of service personnel is at least 3 people
The total power of the engine and heating elements is 15 kW.
Working power per hour - about 10 kWh

Supplied equipment specification:

equipment identification	Quantity, PC.	price, rub.	Amount, rub. in view of VAT	Delivery time, working days
Remote Control	1	100000	100000	30
Bobbin creel	1	20000	20000	30
Impregnating bath with tensioning device, spiral winding device, leveling device	1	120000	120000	30
Annealing chamber	1	60000	60000	30
Water cooling unit	1	15000	15000	30
Pulling device / cutting unit	1	160000	160000	30
Rebar coiler	1	120000	120000	30
Roving twist device	1	80000	80000	30
Technical data sheet for the line	1	-	-	30

Discounts are possible:

When buying for cash.
When buying two or more lines.
When buying a line without installation and training.
Other options are also possible, it is discussed individually.

It is also possible to purchase the line in parts, but without commissioning. We can make any unit according to your drawings.

Could the production of fiberglass rebar become an idea for a profitable business in the field of building materials? This modern analogue of steel reinforcement is distinguished by a number of positive characteristics that make it highly demanded in the market. We will tell you how much money you need to invest in such an enterprise, what equipment you need to purchase and when you can expect to reach a net profit.

Fiberglass or composite reinforcement is a modern analogue of metal reinforcement, surpassing it in terms of quality characteristics. The plastic armature is made of artificial fiber ribbed rods with a diameter of 4 to 18 mm. Often, individual rods are interconnected with synthetic resins for strength.

This is a popular building material that is gradually replacing traditional metal counterparts from the market. It is distinguished by an impressive list of useful characteristics:

High strength. This material is 3 times stronger than steel.
At the same time, plastic material is much lighter than steel - at least 6-9 times.
Does not rust and without damage tolerates exposure to sea or fresh water, acidic or any other aggressive environment.
Dielectric - does not conduct electricity, can be used in insulation work.
Frost-resistant - does not deteriorate even at very low temperatures.
Not affected by electromagnetic fields.
Long service life - at least 50 years.
The ability to make a seamless styling.

As for the disadvantages, we can note the lack of elasticity and poor resistance to high temperatures. Fiberglass reinforcement is not welded, but tied - otherwise it will collapse under the influence of a large amount of heat. Fiberglass rods are so inflexible that they cannot be bent on their own: the rods are bent at the right angle during production. Also, over time, the strength characteristics of the material decrease.

The material is well known among professionals, but ordinary consumers (they are also potential customers of the enterprise) do not distinguish this material from steel reinforcement and often prefer it. Composite rods do not have pronounced marketing advantages, obvious benefits for buyers, which can also be called one of its disadvantages.

Fiberglass or composite reinforcement is a modern analogue of metal reinforcement, surpassing it in terms of quality characteristics

Where is applied

The main field of application of plastic fittings is road, industrial and civil construction. This material is used to reinforce concrete structures, including foundations. Fiberglass reinforcement is well suited for fixing thermal insulation and concrete slabs: it improves the adhesion of concrete elements. The use of such reinforcements lightens the structure and reduces the cost of work.

Resistance to aggressive environments made this material in demand in the construction of concrete structures in chemical plants. High strength ensures the popularity of artificial fibers for bank protection, drainage and sewerage construction. When building roads, it helps to increase the strength and durability of the road surface.

Is such a business relevant

Any production of building materials is a relevant business, and the production of modern and innovative ones is even more in demand. There are a lot of areas of application for fiberglass reinforcement, so a manufacturer of a quality product will always find distribution channels.

The competition in the field is quite high, but the market is not overcrowded. As a rule, in each region there are from 3 to 10 medium-sized enterprises producing such valves.

At the same time, there are much more construction companies and institutions responsible for road construction and bank protection. It follows from this that there will always be demand for the material, so novice manufacturers should initially identify their competitive advantages and actively promote their products.

Composite reinforcement is 6-9 times stronger than steel

Business organization

The production of composite rebar requires an impressive organizational cost. Practice shows that very few people manage to create a full-fledged enterprise for less than 3 million rubles. Equipment and raw materials are expensive. In addition, the entrepreneur will have to provide for working capital for the period until the company sells the first consignments of goods.

A business plan will help you think over your work. It needs to include not only the opening costs, but also the calculation of profitability, the goal for 6 and 12 months, the approximate staffing, as well as a list of potential partners. The sooner an entrepreneur finds stable sales channels, the faster the company will reach the level of net profit.

Production technology

Composite reinforcement is manufactured on a conveyor line. Human intervention in the operation of the equipment is minimal. Production begins with the processing of glass roving - the material is pulled into threads with a cross section of up to 20 microns and impregnated with a special grease agent. The impregnated threads are woven into bundles and dried with hot air. After drying, glass roving is impregnated with epoxy resin.

At the next stage, the threads fall into a special mold for plastic substances (dies), where the diameter of the future reinforcement is determined. Then the workpieces are wrapped with a rope: it provides the required thickness and improves the characteristics of adhesion to concrete.

The formed and wound reinforcement is fired in a magnesite tunnel kiln. There the resins are polymerized. At the final stage, the composite fibers are cooled to room temperature in running water. After that, the material is actually ready for use. It is cut to size with a diamond saw. The cut is precise and even.

Equipment

A conveyor of equipment for the manufacture of composite reinforcement will cost 1-1.7 million rubles. This is the main part of spending on starting a business. The list of machines and equipment includes:

Bath for impregnating glass roving with wringing function.
Dies (molds for plastic substances).
Rebar pulling machine.
Thread twisting machine.
Polymerization oven with temperature control function.
Cooling apparatus.
Diamond saw / rebar cutter.
Apparatus for twisting finished reinforcement.

All machines line up in a conveyor with a length of 15-20 meters. In addition to this equipment, you will need to purchase forklifts, scales, racks for raw materials and finished products. Such a kit will be sufficient for production within a small enterprise.

Production begins with the processing of glass roving - the material is pulled into threads with a cross section of up to 20 microns and impregnated with a special grease

Requirements for the premises

Since the conveyor of machines for the production of fiberglass reinforcement takes at least 15 meters in length and about half a meter in width, the room must have a suitable length. Placement of equipment should be comfortable for workers. Therefore, the area of the premises cannot be less than 200 square meters. The workshop is divided into 3 zones: workspace, warehouse, staff room.

The floor of the room should be flat, without height differences (in extreme cases, no more than 5 centimeters). Ceiling height from 2.5 meters. The manufacture of composite reinforcement requires maintaining a stable temperature regime at the level of 16-18 degrees, therefore, it is desirable to have a special heat control system. Good lighting guarantees quality work, this characteristic should not be ignored. It will not be possible to do without powerful ventilation (with an air outflow of at least 250 liters of air per minute). The location of the workshop does not really matter, you can place it on the outskirts or outside the city.

Raw materials

What materials are required for the production of composite rebar? The basis is glass roving - threads made of molten aluminoborosilicate glass with a diameter of 10 microns. In the manufacture of reinforcement, the fibers are supplied in large sealed bobbins. They are transported at temperatures exceeding 35 degrees and at a humidity level of no more than 70%.

The second key component is epoxy. It is a colorless or light yellow viscous liquid with a honey-like consistency and is used in the primary processing of roving. It makes future fittings resistant to aggressive media.

In addition to these two components, the production of composite reinforcement requires:

braided thread;
alcohol;
acetone;
dicyandiamide.

Business costs

Setting up a business for the production of fiberglass reinforcement will require at least 3 million rubles. About half of this amount will be spent on purchasing equipment and equipping the workshop. Approximately 1 million - for the purchase of raw materials and working capital for the first months of work. It also includes the cost of renting a workshop, transportation and other expenses.

The sum of 3 million rubles cannot be called small. Compared to some other building materials industries, the manufacture of composite rebar is really expensive. The high price is associated with the manufacturability and "artificiality" of the material - in fact, it is entirely prepared from chemical components.

Composite rebar is widely used in construction and road works

Profit calculation

Depending on the diameter, the price for composite reinforcement starts at 10 rubles per meter. But the average cost is higher - 50-70 rubles. Moreover, the material is always sold in large quantities, usually from 1000 meters, that is, the minimum purchase price is 50 thousand rubles. A low-capacity enterprise produces about 2000 meters of material per hour, that is, 16,000 meters per shift. The revenue per shift is about 800,000 rubles. It seems that this is a lot, but part of the funds (about 40%) will be the cost price. The same funds will be used to pay utility bills, employee salaries and other mandatory expenses.

The presence of stable sales channels will help to recoup the investment in an average of one and a half years. Some manufacturers manage to reach the level of net profit faster, but this is rather an exception to the rule. 16-18 months is a more realistic period, given the significant amount of initial investment.

Conclusion

The production of composite reinforcement is undoubtedly a promising direction in the building materials market. To organize an enterprise, at least 3 million rubles will be required, while payback is possible within 16-18 months. Fiberglass reinforcement has proven itself well due to its strength characteristics, but this product is not yet widely known on the market.

Interest in non-metallic fittings arose in the middle of the 20th century due to a number of circumstances. The use of reinforced concrete structures in critical structures operated in highly corrosive environments has expanded, where it was difficult to ensure the corrosion resistance of steel reinforcement. The need arose to ensure the anti-magnetic and dielectric properties of some products and structures. And, finally, it was necessary to take into account the limited stock of ores suitable for steel production and always scarce alloying additives. A practical solution to this problem became possible due to the accelerated development of the chemical industry. In a number of technically developed countries (Germany, the Netherlands, the USSR, Japan. USA, etc.), the corresponding scientific research was started.

At first, an alkali-resistant glass fiber with a diameter of 10-15 microns was adopted as a supporting base for high-strength non-metallic reinforcement, the bundle of which was combined into a monolithic rod by means of synthetic resins: epoxy, epoxyphenol, polyester, etc.

In the USSR (Minsk, Moscow, Kharkov), a continuous technology was developed for the manufacture of such reinforcement with a diameter of 6 mm from alkali-resistant glass fiber of low-zirconium composition grade Shch-15 ZhT; its physical and mechanical properties were studied in detail.

Particular attention was paid to the study of the chemical resistance and durability of fiberglass and reinforcement based on it in concrete when exposed to various aggressive media. The possibility of obtaining glass layer and steel reinforcement with the following parameters has been revealed: ultimate tensile strength - up to 1500 MPa; initial modulus of elasticity - 50,000 MPa; density -1.8-2 t / m * with a glass fiber content of 80% (by weight); working diagram in tension - straight up to rupture (limiting

deformations at this point reach 2.5-3%); long-term strength of reinforcement in normal temperature and humidity conditions - 65% of the ultimate strength; coefficient of linear expansion - 5.5-6.5 × 10 * 6

Experimental prestressed bending elements with such reinforcement under the influence of static loads were comprehensively investigated, technological rules for the manufacture of reinforcement and recommendations for the design of concrete structures with non-metallic reinforcement were developed, and expedient areas of their application were outlined.

Experimental samples of electrical insulating traverses for power transmission line poles were installed on experimental sections of power transmission lines in Belarus, the RSFSR and Adjara. Research has been carried out on the use of glass layer and rock reinforcement in the supports of the contact network and in pressure pipes. Glass-plastic fittings have also found application in polymer concrete baths in electrolysis shops of non-ferrous metallurgy enterprises, in floor slabs at several mineral fertilizer warehouses.

Unfortunately, it was not possible to organize the factory production of fiberglass reinforcement; in small quantities, such fittings were manufactured at the laboratory facility of the NTPO "Beletroynauka" in Minsk.

In recent years, the world began to pay more attention to the study of non-metallic reinforcement made of basalt fiber, the production of which is less labor-intensive, and the raw materials are quite affordable. It can be stated that at present, the basic initial data for the industrial production of fiberglass reinforcement, design and manufacture of various prestressed structures with such reinforcement have been developed, the areas of their application have been outlined.

In Germany, a 7.5 mm diameter fiberglass reinforcement made of aluminoborosilicate fiberglass and polyester resin called "polystal" has been developed and studied in detail. Tests for static, dynamic and long-term loads made it possible to establish the following initial characteristics of this reinforcement; short-term tensile strength - 1650 MPa; modulus of elasticity - 51000 MPa; elongation at break - 3.3%; long-term strength - 1100 MPa; stress loss from relaxation - 32%; stress drop4 at 2 * 106 loading cycles - 55 MPa; coefficient of thermal expansion - 7 × 10 * 6

After testing the experimental beams, the main provisions for the calculation and design of critical engineering structures were developed. In recent years, ten one-, two- and three-span road and pedestrian bridges with polystal reinforcement have been erected. Spans of bridges, reaching 25 m, were reinforced with beams of glass-plastic rods with a diameter of 7.5 mm with tension on concrete. A protective polyamide coating 0.5 mm thick was applied to the rods. The number of rods in the bundle is 19, the working force of the bundle tension is 600 kN.

Special attention is paid to the development of the problem of creating and using high-strength non-metallic fittings in Japan. The production of fibroplastic reinforcement based on carbon and aramid fibers has been mastered, their physical and mechanical properties have been investigated. Wire and ropes are made of carbon fiber with a diameter of 7 microns with a tensile strength of 3600 MPa. The wire is assembled from 12 thousand fibers connected by plastic. Ropes of various bearing capacity are twisted from the wire, which are subjected to heat treatment after the twisting.

A promising range of fittings has been developed, which includes wire, as well as 7-, 9- and 37-shaft ropes with a force from 10 to 100 kN. For example, the characteristics of 7-wire carbon-plastic ropes have been established: ultimate strength - 1750 MPa; elastic modulus - 140,000 MPa; elongation at break - 1.6%; density - 1.5 t / m3; stress relaxation - 2.5%; heat resistance - 200 JC; high acid and alkali bone.

Reinforcement made of aramid fibers with a diameter of 3 to 16 mm with a breaking strength of 8 * 250 kN has been developed. The rods are obtained by braiding into bundles of continuous fibers, followed by impregnation with plastic and heat treatment. Ultimate elongation of reinforcement at break - 2%, modulus of elasticity - 66,000 MPa. It should be noted that this reinforcement of small diameters (up to 5 mm) is suitable for transverse spiral reinforcement ^ structures. BUT

In Japan, a significant complex of research has been carried out on experimental beam structures with various types of non-metallic reinforcement, automobile and pedestrian bridges of small spans have been erected. Active research is underway on the possibility of using carbon fiber reinforcement in various areas of construction. Thus, high-strength carbon-fiber-reinforced plastic tapes of various cross-sections began to be used to strengthen reinforced concrete structures in critical structures in operation.

It is worth noting the pioneering work carried out in the Netherlands with non-metallic aramid fiber reinforcement. The accumulated material on the properties of such rectangular and circular reinforcement was first reported at the FIB congress in 1986 and aroused great interest. Later, in the same country, a composite wire with a diameter of 5 mm was developed from carbon fibers and an epoxy binder. The tensile strength of the wire ranges from 2300 to 3300 MPa, depending on the strength of the fiber and the proportion of its content in the section. The production of such a wire has been mastered and experience has been gained in its use as prestressing reinforcement in piles. The prospects of using beams made of composite wire in cables of long-span bridges and for external reinforcement of various prestressed structures are noted.

A large experiment was carried out by scientists from the USA and Canada on one span of a prestressed girder road bridge reinforced with Japanese-made carbon fiber wire and ropes. The use of modern measuring systems and the continuation of tests up to failure allowed obtaining an extensive set of data necessary for a positive assessment of bridges with such reinforcement.

The constant growth in the number of publications on high-strength non-metallic reinforcement and the active work of the FIB commission on this topic confirm the promising nature of this material for prestressed reinforced concrete and the need for a more attentive attitude to this problem in the world. \

2.Historical development and experience of using composite reinforcement in the USSR, Russia and abroad

And finally, it is necessary to take into account in the future the limited stock of ores suitable for meeting the continuously growing demand for steel and always in short supply of alloying additives.

At first, a continuous alkali-resistant glass fiber with a diameter of 10-15 microns was adopted as the supporting base of the developed high-strength non-metallic reinforcement, the beam of which was combined into a monolithic rod by means of synthetic resins (epoxy, epoxyphenolic, polyester, etc.).

In the USSR (Minsk, Moscow, Kharkov), a continuous technology was developed for the manufacture of such reinforcement with a diameter of 6 mm from alkali-resistant glass fiber of low-zirconium composition grade Shch-15 ZhT, and its physical and mechanical properties were studied in detail.

Particular attention was paid to the study of the chemical resistance and durability of fiberglass and reinforcement based on it in concrete in various corrosive environments. The possibility of obtaining fiberglass reinforcement with the following indicators was revealed: tensile strength up to 1500 MPa, initial modulus of elasticity 50,000 MPa, density 1.8-2 t / m3 with a weight content of fiberglass 80%, the working diagram under tension is rectilinear up to rupture, ultimate deformations to this the moment reaches 2.5-3%, the long-term strength of the reinforcement in normal temperature and humidity conditions is 65% of the ultimate resistance, the coefficient of linear expansion is 5.5-6.5 × 10 * 6.

Experimental prestressed bending elements with such LSD reinforcement exposed to static loads were comprehensively investigated, technological rules for the manufacture of reinforcement and recommendations for the design of concrete structures with non-metallic reinforcement were developed, and expedient areas of their application were outlined.

Experimental samples of electrical insulating traverses of power transmission line supports were developed, the manufactured samples were installed on experimental sections of power transmission lines in Belarus, Russia and Adjara. Research has been carried out on the use of fiberglass reinforcement in contact network supports and in pressure pipes. Stacks about plastic fittings have also found application in polymer concrete baths in electrolysis shops at non-ferrous metallurgy enterprises, in slabs at several warehouses of mineral fertilizers.

Unfortunately, it was not possible to organize the factory production of fiberglass reinforcement at that time.

In the 70s of the XX century, non-metallic reinforcement was used in structures made of lightweight concrete (cellular concrete, wood concrete, etc.). as well as in foundations, piles, electrolysis baths, beams and girders of overpasses, supporting structures of capacitor banks, slope attachment plates, without insulator traverses and other structures.

In 1976, two sliding warehouses were built in the districts of Rogachev and Cherven. The supporting inclined elements of the upper belt of the arches are reinforced with four prestressed fiberglass rods with a diameter of 6 mm. The rods are located in two grooves with a section of 10 × 18 mm. elements selected in the bottom plate. The support sections of the elements (in the ridge and support nodes) are reinforced with 20 mm thick wooden planks.

Saving wood in load-bearing reinforced elements was 22%. the cost was reduced by 9%, the mass of the structures was reduced by 20%. The cost of the construction in comparison with the existing standard solutions of warehouses of the same capacity has decreased 1.7 times.

At the acid station of the Svetlogorsk Artificial Fiber Combine, the ceilings above the technological galleries are made of FAM polymer concrete with glass layer and reinforcement. The slabs were reinforced with 6 mm fiberglass rods with prestressing of the ribs and slabs in the transverse direction. The shelf distribution fittings are pre-stressed. The economic effect as a result of a decrease in the reduced costs per 1 m2 of overlap amounted to 57.95 rubles.

In 1969, the IS&A Gosstroy of the BSSR, together with the SE "Selenergoproekt" (Moscow), developed and investigated electrical insulating traverses for 10 kV transmission lines and 35 kV transmission lines.

In 1970. in the region of Kostroma, a pilot section of a 10 kV power transmission line with fiberglass-concrete traverses was put into operation.

In 1972, in the region of Stavropol, a pilot section of a 35 kV power transmission line with electrical insulating fiberglass traverses was put into operation. The traverse structure consisted of three prestressed fiberglass concrete elements (beams), bolted on a steel plate, which was fastened with clamps to the top of the reinforced concrete support.

In 1975, in Grodno and Soligorsk, two experimental sections of 10 kV power transmission lines with fiberglass reinforced plastic traverses were commissioned. The design of the traverse is prefabricated, three-beam, consists of two rectilinear prestressed fiberglass concrete elements: a horizontal one, on which two wires are located, and a vertical one, on the top of which a third wire is attached. The prefabricated traverse by the base of the vertical element is attached to the reinforced concrete support of the power transmission line using steel clamps. The traverses are made of electrically insulating concrete. Armature - four rods with a diameter of 6 mm in each element.

In 1979, in the region of Batumi, two experimental sections of power transmission line supports for 0.4 and 10 kW with traverses made of concrete polymer reinforced with fiberglass reinforcement with a diameter of 6 mm were put into operation.

The Ust-Kamenogorsk non-ferrous metallurgy plant has mastered the production of prestressed electrolysis baths from FAM polymer concrete reinforced with 6 mm diameter fiberglass rods. The dimensions of the bath in the plan are 1080 × 2300 mm, the height is 1650 mm, the wall thickness is 100 mm. The walls and bottom are reinforced with double symmetrical reinforcement with bar spacing of 200 mm. The economic effect per bath, excluding the costs associated with stopping production when replacing reinforced concrete baths, is 1015.5 rubles.

In 1975, according to the project of the Department of Bridges and Tunnels of the Khabarovsk Polytechnic Institute, the construction of the world's first glued wooden bridge 9 m long was completed, the beams of which with a cross section of 20 × 60 cm were made of spruce wood and reinforced with four prestressed beams of four fiberglass rods with a diameter of 4 mm.

The second bridge in the USSR with fiberglass reinforcement was built in 1981 in the Primorsky Territory across the river. Shkotovka. The superstructure of the bridge consists of six metal I-beams # 45. prestressed with ties of 12 fiberglass rods with a diameter of 6 mm. The beams are united by a monolithic reinforced concrete slab of the roadway. The superstructure has a length of 12 m, the dimensions of the roadway and sidewalks are G8 + 2x1 m. The design loads are N-30, NK-80.

In the Khabarovsk Territory, a bridge with the use of fiberglass reinforcement was built in 1989. In the cross-section of a 15-meter span, 5 ribbed beams were installed without broadening in the lower zone of the beams. The reinforcement of the bridge span beams was taken as a combined one: the creation of initial stresses in them was carried out by four bundles of 24 fiberglass rods with a diameter of 6 mm in each and one typical bundle of steel wires. Reinforcement of beams with non-prestressing reinforcement of classes A-I and A-ll was left unchanged.

Historical development of the use of composite reinforcement abroad
(based on materials from the USA Concrete Institute)

The history of FRP rebar development can be traced back to the widespread use of composites after World War II. The benefits of the high strength and lightness of composites were widely recognized in the aerospace industry, and during the Cold War, advances in the aerospace and defense industries led to an even wider use of composites. Further, in a booming economy, the United States needed inexpensive materials to meet consumer demand. Coaxial fiber production has become a fast and economical method for forming parts with constant cross-sectional profiles, and composites made from continuous fibers have been used to make golf clubs and fishing rods. However, only in the 60s, these materials began to be seriously considered in the production of reinforced concrete reinforcement.

The proliferation of Federal Expressway Systems in the 1950s exacerbated the need for year-round maintenance. Salt is widely used to remove ice on road bridges. As a result, the main concern has become the use of steel reinforcement in such structures, as well as in structures under the prolonged corrosive action of sea salt. Various protective coatings have been investigated, including zinc coatings, electrostatic sprayed coatings, polymer concretes, epoxy coatings, and fiberglass reinforcement (ACI 440R). Out of all of the above, epoxy coated steel bars have proven to be the best solution and have been used in aggressive corrosive environments. The use of FRP rebar was not considered an efficient solution due to its high cost and did not have commercial distribution until the late 70s.

In 1983, the first project by the US Department of Transportation was founded, "The Application of Composite Materials Technology in Bridge Design and Construction" (Plecnik and Ahmad 1988).

Marshall-Vega Inc. led the initial development of fiberglass reinforcement in the United States. Initially, fiberglass reinforcement was considered an effective alternative to steel for polymer concrete due to its incompatibility with the characteristics of thermal expansion between polymer concrete and steel. In the late 70s, International Grating Inc. entered the North American FRP market. Marshall-Vega and International Grating have been researching and developing FRP rebar until the 80s.

Fiberglass rods were used in the construction of the decking of the Crowchild Bridge in the Calgary region of Alberta, Canada in 1997.

In the 1980s, there was a demand in the market for non-metallic fittings for specific advanced technology. The greatest demand for electrical insulating fittings was for medical magnetic resonance imaging equipment. FRP reinforcement has become the standard for this type of structure. Other uses for FRP reinforcement have become more famous and in demand, especially in breakwater structures, substation reactor foundations, runways and electronics laboratories (Brown and Bartholomew 1996).

In the 1970s, problems related to the deterioration of bridges due to corrosion caused by chloride ions, the effect of which on steel reinforcement led to a rapid aging of bridges, began to increase in the United States. (Boyle and Karbhari 1994). In addition, the detection of corrosion in widespread epoxy-coated rebar has increased interest in alternative methods to avoid it. Once again, FRP reinforcement has come to be regarded as the primary solution to corrosion problems in bridge decks and other structures (Benmokrane et al. 1996)

Until the mid-90s, FRP rebar was most widely used in Japan. even then in the country there were more than 100 commercial projects with its application. Details of FRP design were included in JSCE Design and Construction Guidelines (1997). In Asia, recently, China has become the largest consumer of composite rebar, using it in new structures ranging from bridge decks to underground works (Ye et al. 2003).

Glass plastic fittings were used in the construction of a winery in British Columbia in 1998

The use of FRP reinforcement in Europe began in Germany with the construction of a prestressed FRP road bridge in 1986 (Meier 1992). After the bridge was built in Europe, FRR reinforcement research and use programs were launched. The European BRITEEURAM Project, Fiber Composite Components and Nonmetallic Reinforcement Technology, tested and analyzed FRP materials from 1991 to 1996 (Taerwe 1997) ... Later, EUROCRETE took the lead in a European research and demonstration program.

Canadian civil engineers have developed application guidelines for FRP reinforcement for the Canadian Road Bridge Design Code and have built a series of demonstration projects. The Headingley Bridge in Manitoba used reinforcement from CFRP and GFRP (Rizkalla 1997). In addition, during the construction of the bridge on Kent County Road No. 10, CFRP reinforcement was used to reinforce negative moment zones (Tadroset al. 1998).

During the construction of the Joffre Bridge over the Saint-François River, located in Sherbrooke. Quebec, CFRP fittings were used on pressure plates and GFRP fittings on roadblocks and sidewalks. The bridge, which opened to traffic in December 1997, was equipped with fiber optic sensors integrated into the FRP reinforcement structure for remote deformation monitoring (Benmokrane et al. 2004). Canada remains a leader in the use of FRP reinforcement in bridge deck construction (Benmokrane et al. 2004).

In the USA, widespread use of FRP rebar has been reported previously (ACI 440R). The use of GFRP fittings in the construction of magnetic resonance imaging hospital ward extensions is becoming ubiquitous. Also, composite reinforcement has become a standard solution in industries such as harbor structures, overhead reinforcement mesh for bridge decks, various factory-made reinforced concrete products, ornamental and architectural concrete. Some of the largest projects include the Mayo Clinic Gonda Building in Rochester, Minnesota, the National Institutes of Health in Bethesda, Maryland, for magnetic resonance imaging, the Potter County Bridge in Texas, and the Bettendorf Iowa Bridge, for reinforcement. flooring (Nanni 2001).

GFRP reinforcement was used in the tunneling of a concrete wall that needed to be built after the tunnel boring machine, and has since been widely used in the construction of many of the largest metros in the world, including Asia (for example, Bangkok, Hong Kong and New Delhi) and Europe (for example , London and Berlin).

Source: ACI 440.1R-06 Guide for the Design and Construction of Structural Concrete Reinforced with FRP Bars. (Reported by ACI Committee 440).

Experience in the development and application of non-metallic fittings in Russia

2000s

At the initiative of the Moscow government in 2000, studies were resumed to develop basalt-plastic reinforcement with increased durability. NIIZhB conducts work in conjunction with FSUE "Research Center MATI" them. K.E. Tsiolkovsky and JSC "ASP" (Perm).

Developed and installed two pilot plants based on the traditional principle of pultrusion and a new beefeller technology. The latest technology provides a significantly higher productivity in the production of composite nonmetallic basalt-plastic and fiberglass reinforcement, therefore this technology has been chosen as the most promising.

Replacing steel reinforcement with non-metallic one eliminates damage to reinforced structures due to steel corrosion and destruction of the protective layer, and allows you to maintain the quality and appearance of structures during operation, reduce operating costs by increasing the overhaul period.

Non-metallic composite reinforcement (NKA) is recommended for use in concretes, which are characterized by a reduced protective effect in relation to steel reinforcement:

in concretes based on Portland cement with an alkali content of no more than 0.6% went to Portland cement, pozzolanic cement, mixed binders (gypsum-pozzolanic, cements with low water demand, with a high content of active mineral additives);
in monolithic concrete with chlorine-containing anti-frost additives that do not contain alkalis (calcium chloride HC, nitrate-calcium chloride NHC, nitrate-chlorine calcium with urea NHKM, etc.);
in coarse concrete for drainage pipes, light coarse concrete, monolithic aerated concrete;
for reinforcing structures exposed to aggressive chloride environments; paving slabs, road surfaces, etc.

The recommended area of application of NKA is the outer layer of three-layer panels and flexible ties, which allows to improve the appearance of the building (no rust streaks) and to increase the thermal performance of walls, as well as in layered walls with flexible ties.

An effective area of application for NCVs is structures exposed to leakage currents. With the receipt of experimental data for a longer test period, the improvement of the ABP properties, the scope of application of non-metallic fittings can be expanded.

Based on the results of the examination of three bridge spans, the supporting structures of which are prestressed with glass with plastic reinforcement, conclusions can be drawn;

The superstructures of the test bridges made of laminated timber (31 years of operation), the steel-reinforced concrete superstructure (25 years of operation) and the superstructure of fiberglass concrete (17 years of operation) retained the effect of the pre-stressing of the ASP.
The use of ASP as anchors in load-bearing structures based on epoxy resins is justified.
Positive results are obtained from the use of non-metallic composite reinforcement in road and industrial and civil construction.

3.Composite reinforcement - a new stage in the development of construction in Russia

The use of non-metallic composite reinforcement (NKA) in Russian construction began about ten years ago, and during this time it was used without the GOST describing it. Thanks to the efforts of the composite rebar companies, it was finally developed and put into operation since 2014.

In 2003, the use of fiberglass composite reinforcement was allowed by SNiP 52-01 (in particular, it became possible to use it in reinforced concrete structures). The introduction of the new GOST 31938-2012 has raised the use of NSA in construction to a new level, will allow manufacturing companies to significantly improve its quality and even come up with proposals for supplies to the world market.

Manufacturers are confident that the introduction of the new GOST 31938-2012 will lead to a significant expansion of the field of application of non-metallic fittings. They hope to be able to increase sales, and thus profits, as well as improve the quality of the products they offer.

After Moscow, St. Petersburg, Novosibirsk and Krasnodar are actively using it in construction, composite rebar will become popular in other Russian regions that need modern high-tech materials for the construction of residential buildings and industrial structures. The introduction of GOST for NCA products will diversify the market, and consumers will have the opportunity to be convinced of the technological and economic efficiency of the use of composites.

4. Prospects for the use of composite reinforcement in concrete structures

A number of circumstances have led to increased attention of specialists to non-metallic fittings. This interest arose back in the middle of the 20th century. Since the construction is carried out in different climatic conditions and for different needs, it was difficult to maintain the corrosion resistance of metal reinforcement. As a result, the need arose for the use of composite reinforcement, which has anti-magnetic and dielectric properties. And of course, the developing mankind needs to take into account the fact that the ore reserves for the production of metal fittings are not unlimited and the use of artificially created material for the production of fittings has excellent prospects, which rushed into our future.

The emergence of composite reinforcement was not an accident, but a pattern. Due to the intensive development of the chemical industry in developed countries, the first non-metallic fittings appeared.

Fiberglass is used as the main material for the production of composite reinforcement, which is connected into one rod and fastened by means of synthetic resins. The new material has undergone rigorous testing, examined it as well for strength, elasticity, wear resistance, subjected it to various loads in harsh conditions. The studies surpassed all expectations, the material turned out to be quite resistant to various kinds of influences.

Scientists have developed a technology for the production of high-quality non-metallic reinforcement, recommendations for the design of concrete structures using non-metallic reinforcement, identified the most acceptable areas of its application.

In a number of Western countries, non-metallic fittings are used much more widely than in Russia and the countries of the former Soviet Union.

For example, in Germany, fiberglass reinforcement has now been developed and studied in detail, in another way it is called "‘ Polistal * ". The designers have developed projects of bridges, during the construction of which it is possible to use such reinforcement. Over the past few years, more than ten pedestrian and road bridges have been designed and built using such reinforcement.

Composite reinforcement is a particularly significant invention for Japan. Since here, when designing buildings, it is necessary to take into account earthquake-prone areas. In this country, fibroplastic reinforcement based on carbon and aramid fibers is produced. These are very strong and quite resilient rods that are used to construct buildings.

The prospects for the production of fittings and their application in various areas of construction are expanding. A better and more reliable material is being produced that will withstand many destructive factors, such as water, ultraviolet light, electricity.

In Japan, the possibility of using non-metallic reinforcement in various designs is especially actively explored. Automobile and pedestrian bridges are built here, and this reinforcement is also used to strengthen various concrete structures.

In the Netherlands, work is also underway to create a new generation of fittings. It is worth noting that a composite wire made of epoxy bonded carbon fibers was created in this country. The prospect of using such a wire in the production of ropes to support more bridge spans is already near. It will also be used for external reinforcement of prestressed structures.

In recent years, other developed countries, such as Canada and France, have become interested in developments in the field of production and use of non-metallic fittings. USA. and many others.

The number of materials and publications on this topic has increased significantly, research is underway and the properties of such a material as composite reinforcement are being studied. Therefore, the prospect of using it in construction is very weighty, and the study of this material in Russia and the CIS is being carried out in an intensive mode in order to keep up with other developed countries.

5.Dynamics of the composite rebar market

The information concerns the dynamics of the development of the composite rebar market over the past 2 years. After reviewing the statistics of Yandex and Google services, we can conclude that there has been a significant increase in user interest in such a product as fiberglass or composite reinforcement. For example, let's look at the graph of the Yandex statistics service, where you can see the growth dynamics of queries containing the words "fiberglass reinforcement". Those. these are all inquiries of the type "buy fiberglass fittings", "fiberglass fittings reviews", "equipment for the production of glass-plastic fittings", etc.

The absolute values for this request are shown below the graph. For example, in June 2012 there were only 11,605 such requests, and a year later, in June 2013, there were already 25,227. the increase was 217%. Moreover, in both years, the peak of requests falls on the summer months.

For comparison, let's see the data obtained from the analysis of statistics provided by the Google service. The red color on the graph shows statistics for queries containing the phrase "fiberglass reinforcement", there are more queries for it, and in blue, statistics for the phrase "composite reinforcement", these queries are less popular, but their dynamics are similar. Beginning around the second half of 2011 and subsequent explosive growth.

Below we will see a couple of images with information that is interesting enough for analysis. The first image is a map of Russia with regions marked in different colors. The intensity of requests in this region changes from gray and yellow to red. The map shows a slice of data for June 2013.

To understand this image, let's take a look at a short table showing the regional popularity of queries containing the phrase "fiberglass reinforcement".

Regional popularity is the share of impressions for a given phrase divided by the share of all impressions of search results that came to that region. The popularity of a word / phrase equal to 100% means that this word is not highlighted in this region. If the popularity is more than 100%, this means that in this region there is an increased interest in this word, if it is less than 100%, it is decreased.

Impressions per month		Regional popularity
Moscow	3 617	66%
Ekaterinburg	3 109	453%
Nizhny Novgorod	1 684	225%
Permian	1597	507%
St. Petersburg	1209	75%
Novosibirsk	1016	170%
Ufa	909	223%
Rostov-on-Don	818	141%

6.Scope of application of composite reinforcement

According to SNiP 52-01-2003 and MGSN 2.08-01 C and taking into account the properties of AKS fiberglass reinforcement (GOST 31938-2012), it is recommended to use it in the following structures:

7.Trend of the composite rebar market

Research Tec hart estimates the market for composite rebar is growing rapidly. The specialists of this company estimate its growth at 12% per year. According to preliminary forecasts, the growth rate of the composite rebar market should exceed previous years and amount to about 16% per year. The most dynamically developing markets for the production and use of glass layer and steel reinforcement will be such countries as Russia, Kazakhstan, Uzbekistan, Azerbaijan, Armenia.

8.Comparative characteristics of metal and composite reinforcement

Equal Strength Metal Replacement Table
composite reinforcement

9.Advantages of composite rebar

The tensile strength is 2 times higher than the strength characteristics of steel reinforcement;
Stainless material;
The density of composite reinforcement is 4 times less than that of steel reinforcement with a simultaneous increase in elastic strength properties. With an equal-strength replacement of the reinforcing cage, its weight is reduced by more than 10 times. Allows to significantly reduce the cost of transport and handling.
Composite reinforcement is not corrosive in most corrosive environments, including in the alkaline environment of concrete.
The coefficients of thermal expansion of reinforcement and concrete are as close to each other as possible, which excludes cracking when the temperature changes.
The thermal conductivity of the composite is more than 100 times lower than that of steel. It is not a cold bridge and significantly reduces heat loss.
Composite reinforcement does not lose its properties at low temperatures, in contrast to the cold brittleness of steel reinforcement.
The proposed fittings are diamagnetic and have dielectric properties, which makes it possible to use them in buildings and structures such as hospitals, airports, radar stations, and various military structures.
Composite reinforcement increases the service life of structures in comparison with metal reinforcement, especially when exposed to aggressive media.
Does not emit harmful and toxic substances.
It can be produced in any length, directly for the project, which eliminates a large amount of material residues.