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Scientists from Vilnius Gediminas Technical University (VGTU) have developed a new-generation concrete. By adding nanoparticles they have change the material’s structure so that it maintains its original qualities even under extreme temperatures reaching 1,000-1,400 degrees Celsius (1,800-2,500 F).

While experimenting with the material VGTU’s researchers chose to add the nanoparticles of silica (silicon dioxide) to the usual mixture of cement, water and construction aggregate. The outcome was awesome: the basic qualities of concrete have improved dramatically after the nanoparticles of silica were added. For example, the concrete’s ultimate strength and its heat resistance characteristics were performing two times better than previously, while its durability had also increased.

The application of this new technology promises to significantly reduce the maintenance costs of concrete structures, argue the scientists of VGTU.

“Not only does the introduction of nanoparticles significantly improve the basic qualities of concrete; the preparation of our new-generation material is as simple as the preparation of the traditional one,” says Dr. Valentin Antonovič, leader of the research team.  “Users can make it in a usual cement mixer and apply in the construction using the old time-honored methods.”

“More importantly, this upgraded concrete will cost you only 2-3% more than usual, while the other technologies aimed at reaching the same qualities of concrete will make your product, on average, ten times more expensive,” notes Dr. Antonovič.

Although most of concrete mixtures are categorized as A1 Class Combustible, which means 100% noncombustible and suitable to prevent fire from spreading, the regular concrete starts crumbling under the temperature of 600 degrees Celsius (1,100 F) and higher. Therefore, the construction of heat-prone facilities, such as thermal power plants, is highly dependent on the use of special refractory materials.

The product developed by Lithuanian scientists has already been tested in practice, at the medical waste incinerator of Vilnius City in Lithuania. Enriched with nanoparticles, the new concrete allowed the furnace to work nonstop twice as longer than before.

Researchers say the demand for heat-resistant materials will only grow in the future, especially as the use of biomass and biofuel in energy generation is increasing. With the growing popularity of renewables, more and more incinerators will be built, where all sorts of fuel, from peat and coal and straw to municipal waste, will be burnt. The concrete developed by VGTU must be of great avail in these circumstances.

See the original article here (in Lithuanian).

Source: delfi.lt