Porous fillers for light concrete from technogenic raw materials

21st International Scientific Conference on Advanced in Civil Engineering "Construction - The Formation of Living Environment"

土木建筑工程

Tkach, Evgeniya^1 ; Rakhimov, Askhat^2

Moscow State University of Civil Engineering, Yaroslavskoe shosse 26, Moscow

129337, Russia^1

Karaganda State Technical University, Mira blvd 56, Karaganda, Kazakhstan^2

关键词: Anthropogenic origin;    Environmental problems;    Experimental investigations;    Light weight aggregate;    Low temperature synthesis;    Multicomponent mixture;    Physical and mechanical properties;    Technological process;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/365/3/032014/pdf
DOI  :  10.1088/1757-899X/365/3/032014

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

The actual question of the production of porous aggregates for lightweight concrete is to increase their resource base through the use of materials of anthropogenic origin. While porous aggregates should be obtained taking into account the reduction of energy consumption, while addressing issues of disposal of industrial wastes. The purpose of this study - obtaining foam-glass-crystal porous aggregates for lightweight concrete, according to the technology of low-temperature foaming. The object of study was industrial waste production in Central Kazakhstan that contains silica and aluminosilicate components as the main component (slags, ashes of thermal power plants, tailings). The results of experimental investigations showed the possibility of obtaining foam-glass-crystal porous aggregates for lightweight concrete based on two-component and multicomponent mixtures composed of one kind of man-made materials, their mixtures in different ratios, and corrective additives. The paper discusses the two stage technology for obtaining foam-glass-crystal porous aggregates for lightweight concrete based on powder method, and includes two main stages: obtaining of will stekloagregat in terms of low-temperature synthesis and preparation of the foaming mixture of glass powder with blowing agent, conducting a foaming process obtaining a final aggregate. The processes of formation of structure occur at lower temperatures (not above 9000C) compared with the process of obtaining foam glass and expanded clay with a significant reduction in the overall time of the technological process, which significantly reduces the energy consumption. The resulting porous aggregates are characterized by high physical and mechanical properties: density 200-220 kg/m3; strength of 3.1-4.0 MPa; water absorption of 1-2%. Samples of lightweight aggregates are characterized by a high degree of homogeneity of the pore structure and is preferred for strength and conductivity pore sizes up to 1.2 mm and interporous partitions is 50 microns. Confirmed that the obtained porous fillers for light concrete unlike traditional fillers (agloporit, expanded clay), can withstand higher loads without degradation due to the presence of the crystal structure of interporous partitions. The material has a low water absorption compared to concrete block, that indicates the ability to maintain their thermal performance over time, and has virtually unlimited lifespan. For production of porous aggregate for lightweight concrete can be used in conventional industrial heating equipment used in the manufacture of bricks and ceramics. The results for obtaining foam glass crystal materials from industrial waste, allow us to conclude on the possibility of developing technological schemes for the production of porous aggregates with high physical and technical properties. Established in principle the possibility of using technogenic waste of the industry, that allows us to solve the environmental problems of waste disposal and to expand the raw material base for the production of porous aggregates for lightweight concrete.