Is it possible to create building material which would be some kind of analogue to fragile glass: possess concrete’s strength and at the same time transmit light?
Scientists thought up how to combine these likely incompatible properties in one and invented material of the future which is as good as its foreign analogues. And now the scientists are working on imparting it with new characteristics.
Ice castle is not a fantasy!
A light and transparent fairytale castle had been a dream of Russian empresses. Let us recall the “house of ice” of Anna Ioanovna, or the Amber Room in Catherine Palace… Nowadays this dream has become more realizable due to existence of high technology in architecture.
Let us remind that light-transmitting concrete called litracon was invented by Hungarian architect Aron Losonczi at the beginning of 2000s. He combined concrete and optic fibre in one material, which transmits light and makes buildings look like an inimitable fairytale-like installation. This break-through innovation has already started being introduced at the market of architectural decorations in Japan and the USA, but it still hasn’t found its application in Russia. Composition of litracon is being kept in utmost secrecy; besides, it is a very expensive technology, and in our country it is considered to be an architectural wonder. Is it possible to uncover the mystery of translucent concrete and make its production less expensive? Is it possible to impart him with new properties which would expand the sphere of its application?
“This is exactly the goal we have set,” says project leader Galina Averina, postgraduate of the SUSU Institute of Architecture and Construction’s Department of Building Materials and Products. “A year ago we started testing various components of light-transmitting concrete: cement-sand and marble mixtures reinforced with plastic fibres. Manually, layer after layer, we were placing pieces of optic fibre directed to the side of light source on concrete, gluing them in a bundle. The secret of transparency is dispersed reinforcement with optic fibre, a material with fine-fibrous structure which permits light through.”
According to Galina Averina, the difficulty was in the fact that setting of the lower layer of concrete was too slow, and a new layer can be placed only when the previous one has hardened. But the scientists found the solution: they started experimenting with admixtures which speed up setting of concrete mixture. The finishing touch is thorough smoothing of such plate, which enhances its light-permitting ability and inimitable sparkling effect.
The Phantom of the Opera
At World Robot Olympiad‑2018 exhibition, where the young scientists presented their extraordinary concrete, the invention excited big interest. Visitors were asking where they could get the unique material and whether the scientific invention will be further developed.
“So far this is just an experiment, a laboratory sample,” says Galina Averina. “But we hope that it will excite interest among investors, and production of light-permitting concrete will be organized. We have many ideas and plans about how to impart the concrete with new properties and reduce its self-cost. For example, we could apply finished fiberglass cloth, which would make this labor-consuming process much cheaper. Another idea is to produce such concrete not just in the form of panels but also as a monolith! So far this is just an idea, but it is quite implementable. I am sure that the difficulties with manual layer packing will be overcome, and the technology will be automated.”
Nowadays, litracon is mainly used as decorative finishing material only in low-rise construction, but as soon as it gets produced in monolithic version, it will become applicable for construction of high-rise buildings as well.
“Sphere of use for this material is very wide,” assumes Galina Averina. “This is both esthetics and economy: walls serving as windows provide enough light. In Leipzig, Germany, translucent concrete was used in construction of the BMW group company representative building; in Aachen it was used to panel one of skyscraper’s facades. At that, the panels were connected to a computer light control system, and the building transformed into a giant screen of light show! In Hungary, such concrete is used in making benches, torches, and other small architectural forms. These inventions, in my opinion, may come in handy in Chelyabinsk, where the program for developing a comfortable city environment was launched.”
According to the plan of architects, translucent concrete can completely transform the design of night illumination of gazebos and fountains. Buildings made of this material shine at any time of the day: at daylight, the light penetrates from the outside; at night it comes from the inside, creating an illusion of fantastic show of light and color.
Moreover, properties of this material can be applied in shadow play shows; if such concrete is used instead of a folding screen, silhouettes will possess some kind of a “living shell”. For example, The Phantom of the Opera will be able to amaze its spectators with an effect of presence of ominous creature from the otherworld!
Dolomite instead of cement?
For all that, what is the new that our scientists brought to this innovative technology?
“We are working on it,” says Galina Averina. “For example, why not use our previous invention which can easily become a component of translucent technology? Four years ago, having won at a contest held by Russian Foundation for Assistance to Small Innovative Enterprises in Science and Technology, we received a grant for invention of building mortars on the basis of manmade dolomite. In these mortars, magnesium binding powder is used as a binder instead of cement; the powder can be obtained out of dolomite wastes from refractory industry. For example, there are entire mountains of refuse heaps of Magnezit industrial complex near the city of Satka; if we use this waste material in production, both economics and ecology will gain profit. This topic is one of the key issues of my future Candidate’s dissertation. We are developing a series of materials that can be widely used, starting with mortars for sealing shafts of closed mines, and finishing with light-transmitting concrete. For that, we are planning to attract investors and create a small innovative enterprise.”
As the inventors explained, the main advantage of magnesium powder, compared to traditional cement or lime, is its high water resistance. At that, products on its basis don’t require treatment with high temperature. Magnesium-based components can become a valuable binding component of translucent concrete! Their unique property is the ability to harden not with the use of water like cement, but in an interaction with salt solution!
“In a bond of magnesium oxide with chlorine salts, so-called compounds of hydroxydchlorides get formed; they possess enhanced compressing and flexing strength,” adds Galina Averina. “We studied the possibility to control deformations of such compositions, which is especially important in joint-free construction. But not less valuable is such property of magnesium binding powders as biocidity – the ability to resist biological corrosion, such as fungi and mold. Flaws in designing and utility systems laying may result in moistness and appearance of mold on the walls of a building. Fungi spores, in turn, worsen the quality of air in a room, which can lead to labored breathing and asthma. There is no such danger when using magnesium-based structures!”
A printed “transparent house”?
Meanwhile, production of light-transmitting concrete might be hindered by shortcomings of “test technology”. For example, how to adjust the concrete for popular today unit construction?
“We are already developing nanotechnology which will help solving this problem,” says one of inventors of translucent concrete, student of the SUSU Institute of Architecture and Construction, Aleksandr Shulmin. “If we add ash and grapheme nano additives to our concrete, its characteristics will qualitatively improve. Which means we will be able to use it to produce not just panels but also blocks – the primary material in low-rise residential construction.”
Besides, the inventors are planning to use plastic components in production of light-transmitting concrete, which also have an effect on its strength and wear resistance. It is nowadays already that such “hybrids” as polystyrene concrete and fibre cement are used in construction. Why not combine them with the “translucent” technology?
“In the nearest future, we are planning to introduce computer modeling of translucent concretes in order to obtain material with preliminarily set properties,” summarizes Aleksandr Shulmin. “One of our ideas is to print such building on 3D printer: first the foundation, then walls and roofing… This is a quite solvable task: nowadays there already are giant printers capable of producing entire cottage houses. And if we combine our technology with ‘smart house’ electronics, we will be able to achieve the most amazing results!”
Based on the materials of newspaper "Yuzhnouralskaya panorama" (“South Ural’s panorama”)