Modern construction technologies involve the use of new materials with improved characteristics. One of the latest developments in scientific and construction organizations– plastic fittings. Thanks to the complex operational properties, it successfully competes with metal rods, which are gradually destroyed as a result of corrosion processes. Glass reinforcement is used to provide an increased safety margin for concrete structures in contact with fresh and salt water, as well as aggressive environments.

Composite reinforcement – ​​fiberglass material for strengthening concrete

Composite fiberglass reinforcement is a new building material made from various fibers:

• basalt;
• glass;
• polyamide;
• carbon.

Fiberglass reinforcement is a building material created on the basis of fibers connected by a complex composition

The name of the polymer reinforcement is determined by the type of fiber used:

• basalt-plastic rods are made from basalt thread;
• fiberglass reinforcement is made on the basis of glass fiber.

Novice developers are interested in whether it is possible to use fiberglass reinforcement for the foundation, and also how fiberglass reinforcement behaves in aerated concrete walls. Modern manufacturing technology, which involves impregnation of a bundle of fibers with a thermoplastic mixture based on polymer components, ensures the required strength of the finished product.

Polymerizing at elevated temperatures, the threads collected in a bundle harden and acquire the required shape. Combining fiber threads can improve performance properties.

Improved adhesion of glass reinforcement to concrete is ensured by applying the following materials to the outer surface of polymer rods:

• fine sand;
• marble particles;
• crushed granite.

Transverse or spiral corrugations increase the strength of the reinforcement and improve adhesion to the concrete mass.

The fibers are bonded together using polyester composite resins

Plastic fittings - features of building materials

Plastic reinforcement, designed to increase the strength of concrete structures, has its own characteristics.

The main difference between this material is light weight, as well as a two-layer design:

• the inner layer is the core of the rod, consisting of longitudinal threads filled with a composite mixture. The core increases the resistance of the material to tensile and compressive loads;
• the outer layer is formed by a group of threads twisted in a spiral. The characteristic arrangement of the outer fibers increases the resistance of the rods to torsion, and also improves the contact of the polymer reinforcement with concrete.

Polymer threads improve the performance properties of composite rods, which successfully compete with standard metal reinforcement. Distinctive Features glass fittings:

• weight reduced by 4-5 times compared to steel rods. The main advantage of the material makes it easier to work and reduce costs associated with transportation;
• The polymer material is twice as durable as steel in terms of tensile strength. This makes it possible to provide the required safety margin with reduced parameters of the outer diameter;
• resistance to corrosive destruction and neutrality to aggressive liquids. Polymer rods retain their properties in a humid environment;
• reduced thermal conductivity coefficient compared to steel. Polymer material allows for the construction and repair of houses, preventing the formation of cold bridges;
• possibility of assembling load-bearing frames without electric welding. This simplifies the process of fixing the bars and also reduces costs.

Fiberglass is used to produce this construction reinforcement

Design features and performance characteristics allow the use of glass reinforcement instead of steel rods to solve a wide range of problems.

Glass reinforcement - types of rods

Plastic fittings are made from different types threads The following types of composite rods are used:

• fiberglass, abbreviated as ASP. The core is made of glass fibers with increased durability to the influence of moisture. The products are used to increase the strength of foundations and road surfaces;
• basalt plastic, marked ABP. Easily distinguished by the black color of basalt fibers. Basalt plastic rods are superior to fiberglass rods in their ability to withstand tensile loads, as well as the magnitude of elastic deformation;
• Carbon fiber rods marked UGP are made on the basis of carbon, used in the production of concrete composites. Increased level the cost of purchasing carbon fiber reinforcement is compensated by the working properties of the material, as well as the ease of working with it;
• combined. Reinforcement with the ACC index is made of basalt and glass fibers and is characterized by increased strength properties. ACC polymer rods on a glass-basalt base are used for special purposes.

The choice of composite rods is carried out depending on the complexity of the tasks.

There are different variations of fitting models, some of which are quite unusual

How plastic fittings are made

The production process of polymer reinforcement is carried out on automated lines and includes the following stages:

1. Filling the feed module hopper with a polymer composition.
2. Feeding composite fibers and ensuring uniform tension.
3. Heat treatment of the material to remove water and oil inclusions.
4. Loading polymer fibers into a tank with heated binding ingredients.
5. Pulling the impregnated threads through a nozzle that winds them.
6. Polymerization of the starting material in an oven at high temperature.
7. Cooling the resulting rods and cutting them into pieces of the required sizes.

The characteristics of the equipment guarantee the quality of the resulting products.

Scope of glass reinforcement

Polymer reinforcement is used to solve various problems:

• production of composite concrete used for construction monolithic structures;
• construction of building foundations and pouring monolithic slabs;
• increasing the strength of walls built of brick;

The scope of application of this building material is extensive.

• construction of port facilities and special structures to strengthen the coastline;
• covering structures highways and strengthening of concrete slopes;
• construction of protective structures for railways and transport highways;
• production of concrete products requiring prestressing;
• construction of transport interchanges, bridges, overpasses and overpasses;
• construction of concrete structures in seismic zones.

Plastic rods do not require waterproofing, regardless of the choice of structural reinforcement scheme. The use of fiberglass reinforcement for concrete reinforcement and the use of polymer rods is carried out on the basis of previously performed calculations. Employees of specialized organizations are familiar with the technique of calculating reinforced concrete for construction.

Advantages of glass fittings

Developers are interested in what the pros and cons of plastic fittings are. Like all building materials, fiberglass reinforcement has disadvantages and advantages. The main advantages of glass fittings:

• increased safety margin;
• acceptable price level;
• light weight of rods;
• corrosion resistance;
• resistance to aggressive environments;
• reduced thermal conductivity;

Plastic reinforcement is used more and more often in construction today, due to its unique characteristics.

• environmental cleanliness;
• long period of operation;
• ease of machining;
• convenient delivery option;
• possibility of assembling frames without welding;
• preservation of properties at negative temperatures;
• dielectric characteristics.

Thanks to a set of advantages, composite rods are popular.

Weaknesses of fiberglass rods

Along with the advantages, glass fittings also have disadvantages.

Main disadvantages:

• decrease in strength properties when heated to more than 200 °C;
• increased likelihood of fire when heated;
• insufficiently high elastic modulus;
• decrease in strength properties during operation and contact with alkalis;
• impossibility of bending rods without the use of special technological methods.

These disadvantages limit the scope of use.

When constructing any building, a foundation is required. To make it stronger, reinforcement is inserted into the concrete. Previously, it was made exclusively of metal. Modern technologies make it possible to produce reinforcement from composites. It has its pros and cons, and therefore before using it in the construction of a bathhouse, you should carefully study the features.

Features of the material

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

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

Peculiarity composite reinforcement is that it consists of two layers - internal and external. Interior- This is a core of fibers arranged in parallel. These fibers are combined with a composite of epoxy or polyester resins. The characteristics of the reinforcement depend on the core.

Fibers are wound onto the core in the form of a spiral, which are also combined with each other using a composite. This part responsible for adhesion to concrete mortar.

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

Pros and cons

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 metal;
• strength;
• resistance to aggressive environments;
• excellent thermal insulation properties, which is the main advantage when building a bathhouse;
• is not a conductor and therefore does not interfere with radio waves;
• service life can be 80 years;
• The reinforcement is sold in coils, 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 elastic. However, the last drawback is important only in the construction of high-rise buildings. In the foundation of a bathhouse, elasticity does not play any role.

If you are not going to heat the foundation of the bathhouse to too high temperatures, then 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 has many advantages - it is light, durable, and not subject to corrosion, which is why it is actively used in construction. However, this material also has certain disadvantages, which are usually not critical, but they still need to be taken into account. They somewhat limit the scope of use of this material. Let's take a closer look at the disadvantages fiberglass reinforcement.

1. Insufficient heat resistance

Despite the fact that the fiberglass underlying the reinforcement is very heat-resistant, the connecting plastic component cannot withstand high temperatures. It doesn't this material flammable - in terms of flammability, this reinforcement corresponds to group G1 - self-extinguishing materials, but at temperatures exceeding 200 ° C, it begins to lose its strength qualities. Therefore, if to concrete structures For any reason, fire resistance requirements are imposed; fiberglass reinforcement cannot be used for them. So you can use fiberglass reinforcement only in those construction fields, where high-temperature heating is completely excluded. It is worth noting that this is quite applicable to any residential construction and to most industrial construction.

It is also worth noting the low fire resistance: if the temperature reaches 600°C, concrete frame practically remains without reinforcement. Consequently, such fittings cannot be used in fire hazardous areas.

2. Low modulus of elasticity

Due to the low modulus of elasticity, fiberglass reinforcement bends easily. If this does not interfere in any way during the manufacture of road slabs and foundations, then when installing floors, special calculations will be required. But at the same time, the elasticity turns out to be sufficient to prevent curvilinear elements from being bent from the reinforcement, so such parts are bent under production conditions.

3. Other disadvantages

Over time, the strength of fiberglass reinforcement decreases, and under the influence of substances that have an alkaline reaction, it collapses. However, a technology has emerged in which rare earth metals are leached from fiberglass, and it becomes insensitive to alkali.

Many consider the disadvantage of fiberglass reinforcement to be the impossibility of joining by welding, although they now prefer to knit metal reinforcement.

Conclusions:

Thus, the disadvantages somewhat reduce the scope of its application, but for mass use for construction purposes they are not at all an obstacle.

2. Low modulus of elasticity

The main advantages of composite reinforcement are its low weight, high tensile strength, high chemical and corrosion resistance, low thermal conductivity, low coefficient of thermal expansion and the fact that it is a dielectric. High tensile strength, significantly exceeding that of steel reinforcement with an equal diameter, it 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 consists of a number of factors, and not just the difference in cost between linear meter steel and composite reinforcement.

Take the time to look at the full description of the factors that make up your savings in money, time, man-hours, electricity, consumables etc. in the article “SAVINGS FROM USING COMPOSITE REINFORCEMENT”

But, you need to remember that composite reinforcement also has significant disadvantages. Majority Russian manufacturers These disadvantages are not advertised, although any construction engineer can notice them on their own. The main disadvantages of any composite reinforcement are the following:

• The elastic modulus 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 application in floors requires additional calculations;
• when heated to a temperature of 600 °C, the compound that binds the reinforcement fibers softens so much that the reinforcement completely loses its elasticity. To increase the resistance of a structure to fire in the event of a fire, it is necessary to take additional measures on thermal protection of structures that use composite reinforcement;
• Composite reinforcement, unlike steel, cannot be welded using electric welding. The solution is to install steel tubes at the ends of the reinforcing bars (in the factory), to which electric welding can already be applied;
• it is impossible to bend such reinforcement directly on construction site. The solution is to manufacture reinforcing bars of the required shape in production according to the customer’s drawings;

Let's sum it up

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

An interesting fact - the reinforcement is in coils!

The main use 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), but later you will need a special device for re-aligning such reinforcement. Will you be able to transport 1000 meters of such reinforcement in your car to the construction site to reduce delivery costs? Now imagine that the specified reinforcement can be replaced with composite reinforcement 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 decreased somewhat. Such reinforcement can be purchased in coils, with the outer diameter of the coil being slightly more than 1 m. In addition, when unwinding such a coil, the composite reinforcement does not require straightening, since it has virtually no residual deformation. Could you imagine that you could transport the reinforcement required for construction country house or dacha, in the trunk of your own passenger car? And you don't even need help loading and unloading!

Reinforcement of concrete monolithic structures plastic materials finds more and more wide application in construction. This is due to such performance qualities as high strength, durability and lack of corrosion. The latter circumstance is especially important during the construction of hydraulic structures, bridges and foundations.

Manufacturers building materials They produce 5 types of composite plastic reinforcement:

• glass composite or fiberglass - ASC;
• carbon composite – AUK;
• basalt composite – ABK;
• aramidocomposite - AAC;
• combined – ACC.

From the name you can understand what material it is basic basis for the production of plastic fittings.

General description and manufacturing technology

Due to its low cost and good performance, fiberglass reinforcement is most widely used. Its strength is slightly lower than other composites, but the cost savings justify its use. For its production use:

• staple fiberglass;
• epoxy thermosetting resins as a binder;
• special polymer additives to increase strength and improve other characteristics.

Composite fiberglass reinforcement for foundations can have a smooth or corrugated surface. According to the manufacturing technology, bundles of the required diameter are initially formed from fiberglass and impregnated epoxy resin. Afterwards, to obtain a corrugated variable cross-section, the surface of the smooth rod is wrapped in a spiral with a cord, which is also woven from fiberglass. Then the resulting blanks are polymerized in an oven at high temperature and, after cooling, cut into straight sections or wound into coils.

Specifications

Production of periodic profiles and technical specifications fiberglass reinforcement are regulated by GOST 31938-2012. The standard defines:

• types of plastic fittings depending on the materials used;
• nominal diameters ranging from 4 to 32 mm;
• the length of straight rods is from 0.5 to 12 meters;
• possibility of supplying materials in coils with a diameter of up to 8 mm inclusive;
• markings and symbols;
• quality control methods;
• storage and transportation rules.

Characteristics of types of composite reinforcement.

The weight of the material depends on the size cross section and can range from 0.02 to 0.42 kg/m.

Weight of plastic fittings.

Data on ultimate strength and elasticity given in GOST show that these parameters exceed the characteristics of rolled steel with the same diameters. This allows the use of polymer reinforcement in particularly critical structures or when it is necessary to reduce the cross-sections of reinforcing materials.

Area and method of application

Plastic fittings are modern alternative rolled metal. The identical shape of the rods allows its use using technology similar to steel. A reinforcement frame made of composite plastic reinforcement is formed in the form of a flat mesh or spatial structure designed to strengthen and increase the strength of reinforced concrete monoliths.

Polymer reinforcing materials are used in the construction of roads, bridges, hydraulic structures, columns, walls, ceilings, foundations and other monolithic structures.

The main load falls on the longitudinal rods of the structure. They have larger section and located at a distance of no more than 300 mm from each other. Vertical and cross members can be located at a distance of 0.5-0.8 m. The connection of individual rods at intersections is carried out using polymer ties or knitting wire. The joining of individual rods on one horizontal line is carried out with an overlap.

Advantages of plastic fittings

When comparing composite rods with metal rods (we have already carried out a comparison in this article), a number of pros and cons of plastic reinforcement are clearly identified. These include:

• reducing the weight of the reinforcement frame by 5-7 times;
• higher strength, allowing the diameter of the rods to be reduced;
• corrosion resistance and chemicals in the composition of concrete;
• easy installation and high speed assemblies of reinforcing frames;
• simplified technology for creating round and oval structures;
• excellent dielectric and thermal insulation properties;
• ease of transportation.

In addition, it should be noted the unlimited length of rods for materials supplied in coils, as well as simple cutting of blanks required length.

Reinforcement made on the basis of fiberglass is 20-30% inferior in strength to other composites, but is significantly cheaper. Therefore, such material is in higher demand in construction.

Flaws

Among the main disadvantages of composite reinforcing materials, experts call:

• low maximum temperature of use, not exceeding 60-70°C;
• poor mechanical stability under lateral loads;
• the impossibility of bending with a small angle of curvature and the need to use special elements.

It should be noted that there is no regulatory framework on the use of polymers for concrete reinforcement and, often, unreliable technical data from the material manufacturer. This makes calculations difficult and forces us to assemble structures with a safety margin.

Technology of foundation reinforcement with composite materials

The low weight of plastic reinforcement for the foundation simplifies the process of assembling a reinforcement frame of any design. At the same time, thanks to increased strength material, the cross-sectional diameter is taken one number less than for metal analogues.

The technological process of installing concrete monolithic structures using polymer rods consists of the following stages:

1. installation of formwork and marking the pouring level concrete mixture;
2. assembly and installation of the reinforcing frame;
3. pouring concrete into formwork;
4. removal of formwork panels.

Work on the installation of reinforced monolithic structures must be carried out in accordance with the adopted design decisions. The deck configuration must fully correspond to the size and shape of the foundation. As formwork material, you can use standard factory-made panels, boards, moisture-resistant plywood or chipboard. For permanent formwork Expanded polystyrene sheets are most often used.

After assembling and securing the formwork panels, they inside, using a water level, make marks for the upper limit of pouring the concrete mixture. This will reduce the time it takes to complete the job and help distribute the concrete more evenly.

Spatial reinforcing frame for strip foundation

The foundation reinforcement scheme, laying and rod diameter are always indicated in the project. The use of composite reinforcement, especially those based on carbon fiber, makes it possible to reduce the diameter of the rods by one size. The laying of the material must exactly correspond to the calculated data. The frame is assembled on a level area.

The work begins with cutting the workpieces. To do this, pieces of the required length are unwound from the coil and placed on stands at a height of 35-50 mm above the support pad or ground. After this, the transverse jumpers are laid according to the drawing, and at the intersections they are tied with wire or ties. In this way it will be collected bottom row spatial reinforcement frame.

At the next stage, it is necessary to assemble a lattice completely similar to the first one, lay it on top and then cut the vertical posts to the designed length. The first post is tied at the corner of the flat gratings, the second - at the adjacent intersection, as a result, this gradually forms spatial design. If there are more horizontal rows, then the second grid is fixed at the required height, and then the next one is fixed. The vertical post in this case is one whole segment.

When assembling the frame, you must remember that the ends of the reinforcing bars should be located at a distance of 35-50 mm from the formwork. This will create protective layer concrete and will increase the service life of the structure. For this purpose, it is very convenient to use special plastic clamps.

Plastic fasteners.

It is necessary to pour a sand-crushed stone cushion at the bottom of the trench and compact it well. After this, it is recommended to cover the sand layer with geotextile or waterproofing material. This will prevent moisture from entering the concrete and the germination of weeds.

Horizontal reinforcement of slab foundations

When pouring slab-type foundations, horizontal reinforcement technology is used. Her main feature consists in the absence of turning and adjacent sections. Usually these are two grids located one above the other from long straight rods and vertical posts.

All work is carried out on site. First, according to the design drawing, the lower mesh is knitted, and the upper mesh is laid on top of it. After this, vertical posts are installed, as described for strip structures. The lower mesh must be installed on stands.

Pouring concrete onto a plastic reinforcement frame

Technologically, pouring a concrete mixture is no different from work using steel reinforcement. However, given the lower strength of the material under lateral radial impact, compaction with a vibrator should be done carefully so as not to damage the integrity of the plastic rods.