Kaunas University of Technology (KTU, Lithuania) researchers have created unique receipt for ultra-high performance concrete. Produced from local and recycled resources their material has the same compressive strength, but is approximately half the price of the alternatives currently existing in the market.
Because of its flexural strength (resistance to bending), compressive strength (resistance to crushing), denser microstructure and better durability (longer life span) ultra-high performance concrete can have multiple applications. Due to unique structure and properties, it can be used instead of steel in highly aggressive environments, such as nuclear plants, for various machinery, for architectural purposes.
The Lithuanian-produced ultra-high performance concrete for the first time will be used in production of water and fire resistant Eurograde 3 rated safe, which is being manufactured by Lithuanian company Seifuva. This will be the first in the world 3 grade safe, with wall thickness as slim as 42 mm. It is planned that the safe will hit global market in July.
“The qualities of our ultra-high performance concrete, which is used for wall filling, and the metal construction allow for the safe walls to be thinner. This means that the final product is both lighter and cheaper”, says Dr Vitoldas Vaitkevičius, researcher at KTU Faculty of Civil Engineering and Architecture Research group for Building materials, structures and construction technologies.
Researchers admit that they came across producing of unique formula for the ultra-high performance concrete by accident.
“In our field of work, we are constantly trying to use recycled materials. Once we tried to add milled glass into the concrete mixture and were surprised when the compressive strength of the concrete significantly increased”, says Dr Evaldas Šerelis, who has been working on ultra-high performance concrete research for several years.
According to him, the known alternatives of super strong concrete not only have more cement in their structure, but also rarely can be produced from local materials. Ultra-high performance concrete developed at KTU is made entirely from locally resourced materials and recycled glass powder. The final product has a very dense structure, which means that it is resistant to water and certain harmful chemicals, such as chloride.
“Our ultra-high performance concrete can be produced locally under usual circumstances from local and recycled materials. This results in cheaper production: market price of a cubic metre of our ultra-high performance concrete could be around 200-250 EUR, which is up to two times cheaper than currently known alternatives”, says Dr Šerelis.
According to KTU researchers, the main advantage of ultra-high performance concrete is the possibility to build strong, but slender structures. That’s why it is loved by architects and designers. The application of ultra-high performance concrete is not limited to construction industry: KTU formula has already been used for production of concrete handmade home accessories and business gifts.