The new concrete, which improves the quality of the environment, was developed by specialists of the SUSU Institute of Architecture and Construction. When creating an innovative material, scientists focused om obtaining a product with unique properties and low cost. The new sorption-active concrete is made on the basis of industrial waste – overburden rocks of the magnesite deposit (Satka), containing magnesite and dolomite in its composition. The latter is less used in industry and it is stored in dumps. The areas of hundreds of square kilometers occupied by dolomite dumps are withdrawn from economic circulation; mining companies pay taxes to the state for the placement of mining waste on these territories. The developers of the Department of Building Materials and Products of South Ural State University took the mining waste of magnesite and dolomite crushed to a crushed stone fraction as the basis for a new eco-concrete. It is known that precipitation in large urban industrial centers has been acidic for two centuries, it contains a large amount of heavy metal impurities, it destroys soil and has a negative effect on vegetation. Standard concrete pavements on urban highways do not allow water pass through, collect it in the form of puddles and create problems for traffic and pedestrians during heavy rainfall.
“The structure and composition of the new sorption-active concrete were calculated in such a way as to obtain a material with maximum porosity while maintaining high strength”, says Marina Butakova, Associate Professor of the Department of “Building Materials and Products” at SUSU. – All concrete components are firmly joined by cement into a mass that does not collapse under the influence of aggressive elements of urban rainfall and storm drains. Together with colleagues from the Department of “Materials Science” and “Physical Chemistry of Materials” we conducted experiments that confirmed the environmental safety and sorption activity of the new concrete. Sorption-active concrete is absolutely harmless to the environment and due to its sorption properties, it neutralizes dangerous chemical elements in urban storm drains, such as zinc, arsenic, heave metals and ammonia, eliminates the air pollution and soil pollution during evaporation.”.
The strength of concrete was tested by scientists on a hydraulic press. It turned out that five-centimeter layer of porous coating is enough for pedestrian zones and a ten-centimeter layer of sorption-active concrete can withstand a passenger car a KAMAZ truck without cargo. New concrete is laid on road surfaces in the standard way: after compaction of the earth, as well as layers of coarse and fine rubble, a concrete mixture is laid. Concrete plants can produce not only concrete but also paving slabs for pedestrian zones, recreation and suburban areas.
Innovative concrete is suitable for covering the surfaces of pedestrian zones and bike paths, it can replace ordinary asphalt in alleys, parks and playground, as well as on highways with medium traffic intensity. The functional advantages of sorption-active concrete coating in its ability to instantly absorb rain runoff, preventing puddles form accumulating, it will help to reduce the intensity of evaporation and sliding, keep pedestrians’ clothes and shoes clean, protect cars from aggressive substances and generally improve the urban environment.
There is another important area of use of sorption-active concrete. The developers note that the new concrete can be used as the base of landfills for industrial and household waste to prevent harmful substances from entering the soil and aquifers.
The absolute uniqueness of the development of Chelyabinsk scientists is that porous concrete not only passes water but also cleans it from harmful impurities, chemical pollution and improves the environment.
The use of mining magnesite-dolomite waste as a raw material for sorption-active concrete will not only decrease the economic burden on land tenants, but also significantly lower the cost of production of concrete coating itself.
“The technology for manufacturing innovative concrete has been developed and its effectiveness has been proven, - says Marina Butakova. – The University invites mining companies for cooperation, which can transfer waste for the production eco-concrete. This way they will contribute to improving the quality of the environment, reduce their cost and free up land for other types of economic use.”.
The SUSU scientists’ project is being developed within the framework of the “Priority-2030” program in the direction No. 3 “Eco-environment of post-industrial agglomeration”, as well as the national “Ecology” project.