fiber optic concrete. Does it make sense to make transparent concrete yourself?

For more than 50 years, concrete has been the most popular building material. Due to its high strength, density and resistance to temperature extremes, concrete bases last the longest. But, this material has rather meager aesthetic indicators, which significantly narrows the scope of its application in construction. To solve this problem, transparent concrete (or as it is also called light-transmitting or "Litracon") was developed. This is an innovative material that is just beginning to conquer the market. Let us consider in more detail what is included in the composition of this material, what properties it has and where it is used.

What is transparent concrete

This modification was developed by the Hungarian architect Aron Losonci, who experimented with building materials. With his light hand 15 years ago, light-conducting concrete was born, which consists of:

• cement;
• fine-grained sand;
• fiber optic fibers (thread diameter 0.5-2.5 mm), which act as a light-transmitting filler;
• specialized additives that improve the formability of a slow-moving solution.

Coarse fractional fillers are not used in the manufacture of translucent concrete.

Fiber-optic glass filaments must be certified. The documents indicate that the material is environmentally friendly.

It should be said right away that the cost of high-quality transparent concrete is very high, if you have the opportunity, then it is better to order material from Europe. Nevertheless, domestic manufacturers have already begun to master the production technology of this unique composition. True, the price of this has not decreased much.

The cost of transparent concrete

Today on Russian market This unique material is marketed by two companies, Litracon and Lucem. However, it should be borne in mind that these companies are not manufacturers. These are the intermediaries of official European companies that produce luminous concrete. Accordingly, the cost does not include shipping costs.

However, you can order decorative tiles in any size, shape or color. You can even purchase canvases in which fiberglass fibers will be laid out in the form of a logo or product, as well as blocks equipped with LED lighting. Of course, the cost in this case will be many times higher.

If we talk about the price of "typical" panels made of transparent material, then:

• The Litracon Classic prefabricated panel with a size of 1200 X 400 mm and a thickness of 25 mm will cost at least 90,000 rubles. If the thickness is increased to 200 mm, then it will cost 320,000 rubles.
• A little cheaper will be the Litracube Lamp block with a size of 221 X 175 X 175 mm and a thickness of 25 mm. You can pay for it from 54,000 rubles.
• Slab of lightweight concrete from Lucem (1250 X 650 mm) with a thickness of 15-50 mm will cost at least 90,000 rubles.
• A Lucem luminous tabletop with a size of 1200 X 600 mm will cost 89,500 rubles.

Shipping costs are added to all prices.

Many believe that due to its transparent structure, such concrete has very low strength and other characteristics. Let's consider them in more detail.

Properties of transparent concrete

Despite its transparency, this material has the same properties as conventional concrete. Moreover, in some respects, he even surpasses his "gray brother". This is due to the fact that it contains fiberglass, which is an excellent reinforcing material.

Luminous material has the following characteristics:

• strength: for compression in the range of 20-35 MPa, for bending 30 Ptb, and for tension not less than 2;
• density - 2300 kg / cm 3;
• thermal conductivity - 2.1 W / (m∙K);
• frost resistance up to F75;
• water resistance - W4-W8;
• soundproofing properties - 46 dB;
• water absorption within 6%.

At the same time, the material that freely transmits the light beam is not affected by UV radiation. However, there is a risk of minor alkaline silicate reactions in case of heavy rainfall. Therefore, it is better to choose products with a thinner cross-section of threads, then damage will be minimal.

The thickness of transparent concrete slabs usually does not exceed 20 cm. However, this indicator does not affect the light transmission of the material. Even if the wall thickness is 2 m, the light will still pass freely through it.

During the day, the plates let in natural light, and at night - artificial, thanks to which you can achieve very unusual design solutions both in the interior of the apartment, and in the construction of a country house.

Scope of transparent concrete

Since the blocks are available in any size and color, polished or matte, their scope is not limited. Products of this type can be used in construction. They are optimal for interior decoration premises, as well as during the construction of:

• partitions;
• stairs;
• inserts and more.

Luminous panels can be used on a par with standard concrete products. However, the cost of a transparent building material is so high that it is used only in the construction of buildings of special architectural significance.

If we talk about ordinary citizens, then they often use this unusual composite for the manufacture of:

• benches;
• countertops;
• shells;
• decorative fountains;
• illuminated niches in the walls.

If you spend money on small panels, you can make a cube out of them and place a lamp inside it. Thus, you will get a very unusual lamp.

Also, you can make a bar counter from transparent concrete, which will separate the kitchen and bedroom in a studio apartment.

Of course, no one wants to buy panels worth 90,000 rubles for an ordinary night light. In this case, you can try to make a transparent composite on your own.

How to prepare transparent concrete

First of all, it should be said that specialized equipment is required for the production of such a composite. Since the components of the composition are stacked in layers, processing is required after each subsequent layer. However, there are artisanal methods that allow you to prepare a material that resembles transparent concrete with your own hands.

This will require:

• 1 share of PC;
• 2.5-3 shares of sand (it should not contain loam and dust);
• light-conducting filler - (no more than 5% of the total mass of the batch);
• modifying additives.
• 0.5 parts running water.

The solution is kneaded in a forced mixer (it is better to prepare concrete in small portions). First, sand and cement must be displaced. After that, water is added to the mixture, and the solution is stirred for at least 6 minutes. At the following stages, the following operations are prepared and performed:

1. A layer of concrete with a height of about 0.5-1 cm is laid out in the formwork.
2. A layer of fibers is laid on it (they need to be pressed a little into the solution).
3. After that, you need to wait until the layer "grabs".
4. The procedure is repeated until the formwork structure is completely filled.

After that, you must wait about 72 hours and remove the formwork. During the week, the workpiece must be stored at a temperature of +20 degrees and air humidity of at least 95%. After 7 days, the concrete will gain maximum strength, then it will be possible to grind the surfaces. For finishing It is best to use diamond blades.

Finished blocks are mounted using standard masonry mixtures. Epoxy resin with quartz filler can be used for gluing products.

In custody

Transparent concrete is very expensive, so no one uses it to build houses. However, if you use it for decorative purposes, you can achieve a stunning effect.

Transparent concrete is an exotic novelty in the field of construction. Created less than 20 years ago, it turned the idea of ​​​​a gray, unsightly monolith upside down. Hungarian inventor Aron Lokonshi conducted an experiment by laying fiber optic strands in the body of concrete. The result was amazing. Light directed at the surface of a thick impenetrable slab easily passed through it.

Architects and interior designers enthusiastically accepted this idea. Now the construction industry produces varieties of translucent concrete: litracon, luce, lumicon, illuminart. Light illuminated designs of them look elegant and impressive.

The composition of translucent concrete differs from the traditional one in the absence of large aggregates. Thin light-conducting threads are immersed in a matrix of a mixture of Portland cement, sand, water and plasticizers. The solution can be tinted both in classic colors - black, beige, white, gray, and in non-standard ones - green, red, yellow.

In fact, concrete is not transparent, but light-conducting. It is produced with the addition of a special quartz fiber. Getting to the end of the conductor, the light is repeatedly reflected, refracted in bends and exits through the other end. Therefore, the light transmission capacity of the plate does not depend on the thickness, but only on the density of the threads. The larger it is, the more intense the rays penetrate the structure.

In the absence of a light source, it is no different from ordinary. Their decorative properties it shows when illuminated by incandescent lamps, LEDs or sunlight.

The production of products from transparent concrete is quite expensive and not widespread, so the designs are highly priced. Plates are produced with a thickness of 25 mm to 30 cm and standard sizes - 60x120 cm. square meter transparent material reaches 90 thousand rubles, due to the high cost of optical fiber. But light-conducting panels are in demand, their production is growing.

The use of transparent concrete is associated with its exceptional decorative qualities. LED lighting helps to highlight the advantages of the material in the most advantageous way. Piece art objects are made from it - loft-style lamps, luminous tabletops and window sills, benches, niches, wall panels.

In restaurants, cafes and hotels, bar counters, reception, partitions are trimmed with panels. Illuminated floors made of transparent concrete are an adornment of any, even the most concise interior.

Facades and railings made of translucent blocks have an exclusive design. The properties of the material allow it to be used in unusual decision small architectural forms- street lamps, fountains, signs.

The interesting structure of the stone is used in the design of stairs, steps, sanitary furniture.

Components and Specifications

The basis of transparent concrete is high-quality Portland cement grades M300-M700. Fine aggregate - washed quartz sand fraction 2-3 mm, granite or marble chips. To improve the workability of the mixture, plasticizers are used that lower the water-cement ratio.

Optical fiberglass with a diameter of up to 0.25-0.5 mm imparts light conductivity to the composition. It is laid evenly across the thickness of the slab to create a direction for the light flux. You can create illuminated logos, pictures or inscriptions. Fiber content - up to 5%.

In addition to optical permeability, the inclusion of filaments in the composition of the stone gives it high compressive and flexural strength due to the effect of reinforcement. Additive more light-conducting elements increases transparency, but at the same time degrades performance.

Mechanical and physical properties transparent concrete close to the original:

• density is 2050-2400 kg/m³;
• compressive strength not less than 20 MPa;
• frost resistance class up to F100;
• thermal conductivity coefficient 0.1-0.2 W/m°C;
• water resistance W4 - W6;
• water absorption up to 8%;
• combustibility group NG;
• sound insulation index 48-52 dB;
• environmental Safety;
• resistance to UV radiation.

Transparent concrete is not resistant to silicate corrosion in a humid environment, so its surface is treated protective compounds:

• impregnations on a water or silicone basis;
• wax for stone;
• lithium impregnations;
• varnishes.

They give the surface higher wear resistance, resistance to aggressive environments, moisture resistance.

Transparent concrete can be ground, polished, cut, drilled holes in it. Finishing panels are attached to the base by gluing or special inconspicuous anchors. Translucent blocks are laid on solutions with the addition of epoxy resin.

How to prepare transparent concrete

The desire to make your home unique, moreover, spending a minimum of money on it, is close to every craftsman in our country. Making transparent concrete with your own hands is a simple task, requiring only the observance of some rules:

1. Prepare the components for a fine-grained concrete mix - Portland cement M300, sifted clean sand with a particle size of 2-3 mm, water. Volumetric proportions of materials - 1:3:0.5.
2. Dry ingredients are mixed first, then water is added and the mixture is closed. Mixing time - 7-8 minutes. It is advisable to use a construction mixer so that the cement-sand dough is homogeneous.
3. Fiberglass is cut into pieces corresponding to the thickness of the manufactured element.
4. Prepare a sliding formwork in the form of a square or rectangular box. The mixture is poured in layers, so the mold must move vertically.
5. A layer of solution is poured with a thickness of not more than 0.5-1 cm. Segments of optical fiber are sunk into it, observing the stacking vector. If they are located randomly, the light transmission will decrease or disappear altogether.
6. Wait for the moment of setting, and then continue layer-by-layer pouring.
7. After 2-3 days, the formwork is removed, the elements are left until cured for about a week.

For final processing it is necessary to grind the surfaces to remove cement laitance from the ends of the quartz filaments. This will open access to light rays.

Now you can use blocks to finish vertical and horizontal surfaces. During installation, a building masonry mortar, epoxy, polyester or polyurethane adhesive is used.

When fastening to the frame, anchor studs are used, the technology is similar to the device of ventilated facades.

If the tiles are laid on the floor, the surface is treated with protective compounds. This will increase the wear resistance and durability of the coating, facilitate maintenance.

Transparent concrete is a godsend for those who want to create an unusual home decoration. The combination of interesting external properties and traditional performance qualities make it possible to use it both for the manufacture decorative elements, and loaded working structures. In order to save the light-conducting material, you can make it yourself.

In the article we will tell you what transparent concrete is, composition and manufacturing technology. Where transparent concrete is used, its advantages and disadvantages.

General information

Quite recently, just a few years ago, construction market replenished with one more material - transparent concrete. Transparent concrete has another name - litrocon, it is also called luc. Such a material cannot be called absolutely transparent, it cannot be compared with window glass. However, through a wall made of lithrocon, it is quite possible to see the outlines of people, objects or trees. A significant advantage of this material is that a certain volume can additionally penetrate through the walls. sun rays, resulting in a room that becomes brighter. Also, concrete structure, mounted from lyucem, creates the effect of lightness and weightlessness. If you make a wall out of transparent concrete, then the effect of its absence will be created, since the surrounding objects will be visible through such a wall.

Transparent concrete, like ordinary concrete, has good fire resistance, frost resistance, and strength. This material not susceptible to ultraviolet radiation.

The pioneer in the production of transparent material is considered to be the German company Lucem. It was this company that presented this construction material on the market in 2012.

The composition of transparent concrete and manufacturing technology

Lucem production technology involves strict observance provided parameters. In the total mass of an element made using the "transparent concrete" technology, there is a large number of fibers of light guide material. Due to the presence of light-optical fibers, an extraordinary effect of the play of light and shadow is created.

Transparent concrete in its composition contains fine-grained concrete and fiberglass that can transmit light. The percentage of glass fiber content depends on the specified transparency of the manufactured elements. After manufacturing the necessary elements, their surface is subjected to grinding. This operation is performed to give the finished element a finished look and protect it from the adverse effects of external factors.

Finished products made of transparent concrete have all the characteristics of ordinary concrete. Due to the fact that the light-conducting fibers included in the concrete are small in size, the homogeneity of the material is not disturbed.

The technology for manufacturing blocks from litrocon may vary depending on the order received. At the request of the client, blocks can be produced in which optical fiber is located in different ways. This may be a chaotic arrangement, a strictly polarized arrangement, and the fibers may also be arranged in the form of any specific images or shapes. With a polarized arrangement of glass fibers, the effect of transmitting a light flux in one strictly defined direction is achieved. Everyone can buy transparent concrete depending on the order placed.

This technology for the production of transparent concrete has a number of advantages, one of which is that in the twilight or darkness, the lucene structure can glow. If we compare this material with glass or an external light source that illuminates a structure made of ordinary concrete, then transparent concrete immediately acquires anti-vandal properties. Any conventional light source must always be mounted outside, which means that it cannot be protected from the actions of hooligans and encroachments. When installing transparent concrete elements, any light source can be located inside, outside concrete wall. To break it or steal it, you must "first overcome the wall.

From these considerations, the conclusion follows - the use of transparent concrete has a great future in organizing outdoor lighting design on city streets. The bases of park benches, pedestals of any type and purpose, public transport stops - all these elements can be purchased completely new look when using litrocon.

Due to the fact that building transparent concrete is still quite an expensive material, its use in the construction of buildings is limited.

Currently, elements made of transparent concrete are increasingly being used in various fields. Blocks of 1x2 m and 1x1.7 m are considered the most popular and in demand. Such panels are very often used in the design of bar counters, receptions, facing fireplaces, stairs, fountains, etc. this moment the production of structures made of transparent concrete has already been established, which have complex geometry, as well as various shades.

Undoubtedly, this technology has a great future, and maybe very soon we will see luminous multi-storey buildings, theaters, libraries and other buildings that will delight others with their beauty and grandeur.,

With the development of new production technologies, materials that are quite unusual at first glance appear, for example, transparent concrete. The traditional idea of ​​concrete as a heavy stone monolith breaks down already at the first acquaintance with an unusual structure. This is not a trick or a publicity stunt. construction company, this is a real building material, from which, if desired, you can even build a small house.

What is new material

It would be more correct to call transparent concrete light-conducting, because its developer is still very far from being completely transparent. Due to its novelty and limited use, the light-conducting concrete mass is relatively expensive to manufacture, although the technology of transparent concrete does not require special super-complex equipment or unique materials.

For the manufacture of transparent concrete are used:

• Special grades of cement with an extremely small cement grain size;
• Glass quartz fiber in reels;
• Wetting and air-displacing additives for concrete;
• Clean quartz sand, more precisely, dust or powder of high purity.

If you can buy or get all of the listed components cheaply the right quality, then it is quite realistic to establish the manufacture of blocks of transparent concrete with your own hands. So far, the cost of raw materials makes the light guide array quite expensive to manufacture at home.

Note! The quality of fiberglass plays a primary, even a special role in the production of transparent concrete.

Fiberglass, which is traditionally used for fiberglass and materials with a chaotic reinforcement structure, cannot be used to produce a transparent material. For transparent concrete, an intermediate product is required - quartz fiber in threads, which is obtained on special casting machines. This is a semi-finished product, and we need it.

The remaining components are well known to almost any builder. This is Portland cement M300 of the finest grinding and sand, pre-screened, washed and dried.

Properties of a transparent concrete mass

If you try to make a transparent material on chopped fiber, you get ordinary, completely opaque fiber-reinforced concrete. The whole concept of manufacturing a transparent array is based on the use of solid fiberglass with a diameter of 0.25 mm.

Structurally, transparent concrete is just an array of fibers laid in a certain way, filled with a binder matrix based on concrete mortar high fluidity and low shrinkage.

After the completion of the process of setting the concrete matrix of the design strength, transparent concrete demonstrates the following characteristics:

• Strength in static single-line compression corresponds to the level of M250 or good quality concrete of conventional composition;
• Frost resistance at the level of masonry bricks F-50;
• Water absorption is about 6%, which is very high for a cement-based material;
• Light transmission is only 3-4%. But even this value is enough to create the illusion of transparency.

In fact, transparent concrete is a monolith, in which hundreds of thousands of the smallest optical channels are embedded, thanks to which the material is able to project shadows and contours that fall on the cut of the concrete mass even with a casting thickness of up to 200 cm.

That is, it is really possible to see bright light or the contours of an object through transparent concrete; in low light conditions, a light-transmitting material would look like ordinary concrete. If the transparent material were an amorphous monolith, like glass, then a maximum of half a meter of transparency could be obtained.

At the same time, transparent concrete due to reinforcement has high strength for bending and tension, for vibration loading and alternating loading. the material shows acceptable thermal insulation qualities - 2.1 W / m∙K.

From transparent concrete, one could easily build houses and buildings, fences and garages, if not for one problem - the price of the innovative material is only 500-900 euros per square meter of a twenty-centimeter block.

Production technology and application of transparent concrete

A remarkable quality of transparent concrete is the ability to make it in artisanal conditions using a simplified technology. In laboratory conditions, special methods are used to strengthen the concrete matrix, like foam concrete. The result is a light-transmitting material with 2-3 higher specific strength characteristics than concrete made in a garage or shed.

We make high-quality transparent concrete with our own hands

The technique for producing a light-transmitting casting can be found in numerous digests and construction sites, but most of them simply copy the description of the developer. Let's try to make transparent concrete, the closest in quality to the original. First you need to make a collapsible form of plastic or wood with a removable bottom and lid.

Sequence of operations:

• Carefully wash the fiberglass with 647 solvent to wash off the preservative grease from the surface. The fiber must be cut into segments equal in length to the thickness of the future block of transparent concrete;
• We sift cement and sand several times on the smallest sieves, separate all impurities, prepare the batch according to the standard recipe 1:3, add purified water and isopropyl alcohol 1:10. We chop the cement-sand mass with a sharp spatula to squeeze out maximum air;
• We lay a small amount of concrete mass on the bottom of the mold and lay out a layer of fiberglass pieces no more than 1 mm thick. The fibers must be laid strictly in one direction. We embed the fiberglass in the solution with a spatula and press down with a lid;
• The procedure must be repeated until the form is completely filled. We leave the filled block for a day without dismantling, after which we remove the walls and the bottom and lay it out in a humid room for several days.

The result should be a blank that looks like a brick or tile with rough uneven edges. To achieve transparency, the ends of the casting must be ground and polished, initially sandpaper, then with a suspension of pumice powder and water.

The main item of expenditure falls on the purchase of expensive fiberglass, therefore, in handicraft production, they often try to replace it with cheaper polycarbonate fibers of a similar cross section. The technology for making fake transparent concrete is about the same, except for washing the fiber with organic solvents. To improve adhesion with polycarbonate fibers, water-soluble adhesive grades are added to the cement-sand mixture.

Fake transparent concrete is lighter than the original light-conducting matrix, breaks easily on impact, and cracks when exposed to high heat. A real transparent array of mineral fiberglass will easily survive heating up to 150 ° C, since the glass and quartz sand that make up the matrix have the same characteristics.

The use of unusual material

The prohibitive cost of translucent concrete limits its use as a building material. Today, a light-transmitting array is used primarily as a material for the manufacture of lamps, translucent walls and partitions, decorative elements of office interiors, and even as light inserts in the walls of multi-storey buildings.

In the future, transparent concrete, subject to a reduction in production costs, is able to replace most technological window openings and glazing, used for canopies and roofs. Fiberglass can selectively transmit sunlight, therefore, cheap shatterproof panels for greenhouses, sports facilities, ceiling tiles overlap.

Conclusion

At home, transparent concrete is usually used to make lamps, protective panels that replace windows in utility rooms. Partitions in the house are ideally obtained from transparent panels, especially if the layout of the room is made in the form of one large studio. With a wall of light-conducting concrete material, you can separate the kitchen from the living room, make a closet or flower stand.

Hungarian architect Aron Losonczi invented the new building material LiTraCon in 2001. The name stands for light-transmitting concrete, literally translated as light-transmitting concrete. Thanks to the optical fiber included in the composition of the litracon, it is able to transmit light, but only the shadow of the object and its color can be seen through the finished panel. For this property to manifest, a bright illumination with opposite side, otherwise the block looks like regular concrete.

Liquid fine-grained concrete is poured into a special formwork in a thin layer and fiber optic strands are laid parallel to each other across the panel, with a thickness of 2 microns to 2 mm. After solidification, the operation is repeated many times until the mold is filled. At the end of the work, transparent concrete is removed, if necessary, cut into blocks right size, polished. Fiber occupies 4% of the total mass. According to the inventor, litracon is not only glass mixed with concrete, but also new material, whose internal structure and surface are uniform.

In the spring of 2004, Aron Losonzi founded the Litracon Bt company for the production of panels and blocks from litracon. Specifications light-conducting concrete according to European standards:

• density - 2100–2400 kg/m3;
• compressive strength - 50 N/mm2;
• tensile bending strength - 7 N/mm2.

Litracon was primarily intended for the construction of buildings, but due to the high cost of optical fiber and the manual manufacturing method, it was not widely used as a material for building walls. The first object, for which transparent light-conducting concrete was used, was desk lamp Litracube. The lampshade of the lamp is a design of four plates, with a total weight of 10 kg. You can buy it now on the official website of the inventor at a price of 40,000 rubles.

Scope of application

At present, a similar light-conducting concrete, containing up to 5% of light optical elements, under different trademarks(Lucem, Luccon and others) is produced by several European companies. Each manufacturer develops its own innovative technology production of a transparent type of concrete, in order to reduce the cost of production, glass is replaced by plastic fibers or plastic resins. However, the transparent material is still expensive and is most often used for making design elements:

• countertops;
• benches;
• stairs;
• internal partitions;
• building facades.

Since the optical fiber transmits light without significant loss to a distance of about 20 m, the thickness of the light-conducting concrete product is not limited in any way. It does not burn, is highly resistant to temperature extremes, ultraviolet radiation. The wall of the house, during the construction of which transparent concrete was used, will provide greater penetration of natural light into the room during the daytime and illumination of the surrounding area in the evening due to lamps inside the building.

Manufacturers produce ready-made transparent panels in white, gray, black, polished to a mirror finish and matte, rectangular or curved. Blocks can be fixed with anchor bolts, laid out using mortars, glue with compositions based on epoxy resins. On request, transparent panels of individual sizes, colors, different ways surface treatment, with the location of the optical fiber in a chaotic or strict order. In addition, the German concern Lucem has developed a special LED system for uniform illumination of concrete blocks, which is an acrylic panel with a thickness of 10 mm. The control program allows you to use not only white, but also colored light in constant or variable modes.