destruction – no
Materials scientists from NUST MISIS have developed a new fire-resistant steel grade, the university told socialbites.ca.
Due to its increased resistance to high temperatures, it will slow down the destruction of steel structures in case of fire and create an additional time margin for the evacuation of people.
“In case of fire, the metal starts to soften, softens and disappears within 15 minutes under the influence of heat. “The new alloy can last 30-45 minutes,” said Alexander Komissarov, one of the developers of the new steel grade, head of the Hybrid Nanostructured Materials Laboratory at NUST MISIS.
Normal steel quickly loses its load bearing capacity when exposed to high temperatures. This leads to deformation and destruction of building structures, which complicates recovery and extinguishing. It also increases the cost of repair and restoration work.
“We hope to achieve the necessary effect of maintaining the bearing capacity of metal structures in fire conditions at a temperature of 500-700 ° C. This will occur due to the release of fine particles of carbide and nitride along grain boundaries in the metal. These particles will slow down the deformation and buckling process,” Komissarov explained.
Now scientists, together with Severstal, have begun testing the new steel. According to Komissarov, the experiments will be completed this year.
“At the end of 2022, various regulations will come and from next year, finished products will be sold. By itself, fireproof rental will be more expensive than usual. However, the Ministry of Emergency Situations will be able to provide fire protection according to the requirements of the fire service. Now developers use steel in combination with fire retardant coatings – paints that slow down the heating of the main structure. Our steel eliminates this need, making the overall design less expensive. For clarity: a ton of steel will cost 120 thousand rubles, steel plus fire protection – 180 thousand rubles, and our rolled products will cost 150 thousand rubles, so the developer will eventually be able to save 30 thousand rubles per ton, ”said Komissarov.
In addition, the use of this steel makes it possible to reduce the weight of building structures, which will reduce the construction time for industrial buildings, shopping centers, sports facilities and residential buildings. Now steel is being tested for industrial buildings, after completion the material will be tested for residential buildings.
socialbites.ca also contacted the Russian Ministry of Emergencies for comment, but they only promised to provide a response after a full cycle of testing the material from NUST MISIS scientists.
it won’t get any better
Leonid Khazanov, an independent specialist in metallurgy, believes that there will be absolutely no fundamental difference between the use of a new steel grade and the existing ones.
“There is no particular need to construct all buildings in the country using fire-resistant steel: in a fire, the internal structures are damaged rather than the load-bearing ones.
In the event of a fire in a building, the rate of collapse will be affected by a number of factors: source of ignition, area of distribution and exposure time to fire, what material the walls are made of. and ceilings are made, the presence of cracks. For example, if a house is on fire for 1-2 hours and metal structures are exposed to intense heat, this time may be enough to destroy them,” Khazanov explained.
According to him, this is due to the low heat capacity of the steel, which leads to large values of thermal dissipation. Accordingly, the critical heating temperature for structures made from it is in the range of 470-550 ° C.
Varvara Semenova, head of LAW Architect, an industrial design company, noted that the possibility of using a new material in construction primarily depends on economic efficiency.
“Only with the emergence of certain qualitative and quantitative indicators of the new material as an independent unit of fire tests, and with additional fire protection, it will be possible to conduct a comparative cost analysis.”
According to Semenova, the basis of fire safety regulation in the Russian Federation is Federal Law 123-FZ “Technical Regulations on Fire Safety Requirements” of July 22, 2008. According to this document, building structures of buildings and structures, depending on their capabilities, can withstand the effects and spread of fire.
“Today, it is necessary to resort to additional paint or structural fire protection to meet the fire resistance limits of metal structures in terms of loss of bearing capacity. The emergence of a new building material that will eliminate the need for fire protection will undoubtedly please the representatives of the construction industry.