Glass fiber concrete - characteristics, advantages and

Building technologies are actively developing, offering materials with improved qualities. Quite simple, but already quite popular in private construction is one of these new products - based on glass fiber. The material is obtained by combining ordinary concrete and chopped glass monofilament. The article will cover this in more detail, and also you will learn how to create glass fiber concrete with your own hands.

General information

Для обычного бетона, который производится из песка и гравия, свойственна малая прочность на растяжение и сжатие. Причиной этому является компактность зерен наполнителя, а лопанье бетона происходит как раз по их границам (читайте также статью «Железобетонные фермы – размеры, расчет и производство»).

Scientists have come to the conclusion that glass fibers of small cross section, but of rather long length, if they are randomly arranged in the mass of the block and homogeneously mixed, help to increase the strength characteristics tenfold. Ordinary reinforced concrete can also be strengthened through the use of iron reinforcement, which takes tensile stresses on itself.

But, such a solution has "side" effects:

• the weight of the reinforcement is large, so the concrete becomes heavier;
• the dimensions of the reinforced blocks are increasing, since it is necessary to protect the fittings from moisture and corrosion.

Speaking of fiberglass, dispersion-reinforcing block, we can note the following properties:

• greater value of the total cross section in comparison with bars of steel reinforcement;
• its weight is less than that of steel;
• higher values ​​of compressive strength / tensile strength than steel;
• resistance to corrosion, which allows you to make a block of exactly those sizes that are required by the results of the actual calculation of the load, without increasing it to protect the valves.

These qualities contribute to obtaining a lighter and more compact glass-fiber-concrete block, which will have similar strength characteristics and less cost in comparison with it.

Some material properties:

1. The surface of the blocks is polished, which, in combination with indicators such as the thickness of the concrete layer, the nature of the fiber arrangement and the properties of the fiber itself, can give it original effects and even translucency of the material.
2. The material perfectly tolerates coloring, which is carried out both in bulk and on the surface of the finished blocks. To do this, dye is injected directly into the concrete mix or colored fiber is applied.

Advantages and disadvantages

Negative points include:

• low resistance to alkalis, which is why alkali-resistant glass fiber is used for foundations;
• due to the fact that hardening occurs faster than that of ordinary concrete, it is necessary to carry out the laying at a faster rate.

The advantages over ordinary concrete are as follows:

• low weight;
• High tensile, flexural and compressive strengths
• higher (5 times) tensile strength;
• impact strength is 15 times higher;
• frost resistance index reaches 300 cycles.

Application

Благодаря способности материала быстро твердеть и высоким показателям плотности и механической прочности, из стеклофибробетона можно изготовить пластины, толщина которых меньше 10 мм. Это делает возможным формование тонкостенных очень прочных изделий с гладкой поверхностью (см.также статью «Бетонная брусчатка или как недорого обустроить место на участке»).

Due to the plasticity of the material, which is based on fine-grained concrete-matrix, in some cases does not contain sand, you can create:

• textures of any given properties and parameters;
• achieve imitation of different materials;
• get quite complex shapes.

Tip: The use of glass fiber concrete for facade decoration is an excellent substitute for stucco molding of concrete, gypsum or plaster.

Plates of different thickness:

• serve as hinged and ventilated facades;
• able to replace shingles, for example, glass fiber-reinforced concrete roofing will be easier;
• used instead of wall and cladding material.

It is also more promising compared to conventional reinforced concrete when it comes to the construction of floors. Fiberglass concrete has a low weight, and this leads to a reduction in the load on the foundation and load-bearing walls, thereby increasing the floor height of the building being erected.

Composition

Its basis is Portland cement M500-700 white or gray, to which quartz fine sand and alkali-resistant fiber (roving) is added, the use of aluminous cements is also possible.

Improving the aesthetic, molding, technological and operational properties of the material is achieved by the introduction of additives. For shutter glass fiber used water or liquid glass.

Binder has a significant effect on the result. If the basis is alumina cement, reinforced with glass fiber, a more intensive crystallization of tumors is noted. In this case, there is a lesser decrease in strength under equal conditions in comparison with composites, where the basis is Portland cement.

Use of portland cement

Its hydration is accompanied by the formation of a strongly alkaline medium. It is good for steel reinforcement because it provides protection against corrosion, but this environment has a destructive effect on glass fiber.

Calcium hydroxide acts as the main component of the liquid phase of Portland cement, which is in a state of solidification. This compound provokes corrosive processes in the glass, causing the destruction of the silicon-oxygen skeleton.

To avoid corrosive glass fittings, exclusively alkali resistant fiber is added to such glass fiber concrete. This helps to avoid making the unit, just soaked with "liquid glass", but completely unreinforced.

Use of alumina cements

If this material is the basis of concrete, the result is a resistant to aggressive media, waterproof and more dense product. But the price of such cement is high and difficult to buy.

The advantages of the solution are:

• rapid hardening, accompanied by an intensive increase in strength, provides short maturation periods (design strength is achieved in 3 days);
• inertness to fiberglass, which allows to preserve the integrity of glass fiber through less chemical exposure;
• increase the speed of construction several times.

The disadvantages include the fact that these concretes change their strength over time. Be sure to take this into account when designing.

Tip: due to the fact that when working with alumina (as opposed to Portland cement), the errors that have been made become more noticeable, the technological process must be strictly observed.

High strength plaster

If it is planned to manufacture sprayed and dispersion-reinforced products, and even more so when they are intended for interior or finishing works, use high-strength construction gypsum or plaster based on it. The environment of hardening of the stone is almost completely neutral.

And if with respect to steel reinforcement the material necessarily causes corrosion, because it is rather hygroscopic, the hydration medium does not affect glass fiber. The distinctive features of such products is the rapid attainment of strength, fire resistance and low thermal conductivity.

Selection of glass fiber for a specific type of product is performed on the basis of chemical composition and strength.

When choosing a roving, it is taken into account:

• chemical resistance;
• adhesion;
• deformability;
• monofilament linear expansion coefficient;
• strength.

Mainly used:

• quartz;
• silicate;
• натрий-кальций-silicate;
• aluminoborosilicate;
• zirconium silicate fibers.

Of these, only the last type of fiberglass is alkali resistant.

Production

Glass fiber concrete is produced in several ways:

1. Pneumonabryzg, which is done with a special pneumatic pistol. Chopped fiberglass is applied on the form or work surface simultaneously with the cement-sand mortar. Mixing the components of the mixture occurs at the exit from the nozzle of the gun, while the fiber in the solution is introduced evenly. The result is the laying of a homogeneous homogeneous layer of glass fiber cement.

Benefits:

• there is the possibility of a separate preparation of the solution;
• fiber shredding occurs in the gun just before kneading;
• the material is dispensed clearly, mixed quickly, is homogeneous.

Lack of one: the high cost of equipment.

1. Mixing by hand or in a concrete mixer is only suitable for working with small batches.. It can be made by hand, therefore it is widely used in private housing construction.

First, a mortar and sand mortar is prepared in the mixer. Having received the concrete of the required grade, pre-chopped roving fiber (10%) is introduced, continue to mix for at least 5 more minutes.

The finished mixture should be immediately molded, since its hardening proceeds faster than that in which there is no glass. Additionally, you need to seal it by puncture or vibration. The material in this case should be prepared in small portions.

1. Vibroforming, but to be precise, this is not a separate option for producing a mixture, but a method of additional homogenization.. It is used when you need to make products and plates of small size.

It consists in vibro-compacting the concrete placed in the molds on the stand. Need for a more uniform distribution of fiber in the mass.

You can independently make a stand for vibro molding. It is only required to attach the movable tabletop to the mechanism that will create the vibration of the necessary force.

Conclusion

В статье было подробно рассказано о том, что такое стеклофибробетон, а также из каких компонентов его изготавливают. Были описаны способы его производства для промышленного и частного использования. Данный материал по некоторым характеристикам может сравниться с железобетонам, а по другим его превзойти (см.также статью «Бетонный щебень: назначение, характеристики, применение»).

The video in this article will help you find additional information on this topic.