Lightweight concrete with expanded aggregate from siliceous rocks

Abstract

The purpose of this study is to develop technology for the production of a new building composite made of silicon-containing rocks. An aggregate is foamed granules obtained on the basis of diatomite with the addition of caustic soda, dolomite, water and liquid glass. The material composition, materials processing, physical and mechanical properties have been observed. The problem of alkali-silicate interaction typical for traditional Portland cement and glass phase is solved through the use of magnesia binder. Samples on Portland cement and magnesia binder were obtained, the aggregate content was varied. Some aggregate fractions were used to obtain high packing density in the composite. Concrete was estimated according to density, compressive strength and tensile strength, water absorption and thermal conductivity. Analysis of the material structure was made. The results of the study of the microstructure of synthesized concrete indicate the presence of a cement matrix in which granules of various sizes are tightly packed. The results of X-ray phase analysis of synthesized concrete indicates that the cement matrix consists of forsterite crystals. Approximate savings in the use of concrete with the developed aggregate is about 10-20%. Such savings are possible due to the fact the surface occurrence of siliceous rocks allows them to be mined in an open way with minimal costs compared to other rocks, with a lower calcination temperature during material creation.