Granular materials based on expanded sands and their production waste

The article presents the results of studies of granular materials obtained by non-firing technology. For the formation of granules, composite cement and magnesia binders containing waste products of expanded perlite and expanded clay are proposed. Mechanical activation of composite binders intensifies the processes of hydration and structure formation, contributes to increasing the strength of materials. The combination of a binder with a filler in the form of waste from the production of porous aggregates ensures a decrease in the density of the binder, the formation of a finely dispersed porous structure of the composite material, the formation of stable hydrates. The porous structure of the granules is provided by the use of porous sand to form the core of the granules. Studies of the structure of granules by electron microscopy revealed that the reliable adhesion of particles of porous sand with a composite binder stone provides high strength of porous granular materials. Cement granules based on expanded perlite sand are characterized by a density of 300 – 400 kg/m3 and a compressive strength of 1.8 – 2.6 MPa. Magnesia granules based on expanded clay sand have a density of 450 – 500 kg/m3 and compressive strength of 3.5 – 5.7 MPa. The work is aimed at creating effective building materials using resource-saving technology, at the rational use of production waste.