Composite binders from mining waste

The possibility of obtaining composite binders with the addition of mining waste represented by magnesium silicate rocks is considered. They are low active in their natural state. Mechanical activation of raw mixtures was used during carrying out of research works. It was found that with increasing mechanical activation time from 1 minute to 20 minutes, the specific surface of the raw mix increases, the chemical activity of the surface layer increases. It helps to accelerate the solid-phase reactions with the formation of silicates such as diopside, monticellite, mervinite. The optimal time of mechanical activation was determined, at which the largest amount of mixed calcium, magnesium and iron hydrosilicates was noted in the hydrated system. The formation of these products of hydration causes high physical and mechanical indicators of binding compositions. It was found out that during 15 minutes of grinding the raw mix, the flexural and compressive strength of binding compositions at the age of 28 days of normal-humidity hardening reaches a maximum value. The use of mining waste in the production of building materials allows us to obtain new types of products. At the same time, environmental problems associated with the placement of technogenic raw materials are solved.