Study of the local raw materials for usingin the production of the foam concrete materials

Abstract

The article discusses the importance of affordable, high-quality, easily accessible thermal insulation materials for the construction industry, based on the new technologies. It is believed that clay and silicon rocks, which are found in all regions of the Republic of Kazakhstan, can be used as the raw materials for a modified composition, and create favorable conditions for the development of the construction industry. The raw material for the research has been the sand of the “Belaya Gorka” depositof the West Kazakhstan region. The chemical composition of the raw material has been studied by the physicochemical methods of XRD and SEM. The X-ray phase analysis of the foam concrete without impurities consists of the following phases: tricalcium silicate (alite - C3S) - d/n = 1.5; 2.50; 2.67; 2.83 Å; slaked lime (Ca (OH) 2) - d/n = 1.91; 2.62; 4.90,9; Clinker content (%): C3S - 40-68, - d/n = 1.83; 2.40; 2.80; 3.07 Å. According to the mechanism of the foam concrete sintering, in the solution, quartz forms H3SiO4- and H2ЅiO42- ions, the interaction of which with the Ca2 + ions leads to the formation of calcium hydrolyzate, rich in lime on the surface of quartz. As a result, the crystals of successive calcium hydrosilicates are formed in the crystallization medium, and their volume increases. The formation of the CSH (I) phase is influenced by the formation of calcium oxide and the fine grinding of the sand. The formation of the C3S (III) phase of the binder mainly determines its strength. According to the results of the laboratory studies, it has been experimentally proven that the heat-insulating materials with pores of various sizes are formed on the basis of sand.