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Implementation of the development program for the Northern and Arctic territories is not possible without the use of modern materials and technologies in the construction industry. One of the most common and popular building materials is the fine grained concrete, for the production of which, use chemical additives, mainly imported, improving the performance characteristics of the composite. Therefore, the actual problem is the replacement of imported components with Russian-made additives. As such an additive, technogenic raw materials can be used in the form of saponitecontaining waste from the diamond mining industry. For the production of fine-grained concrete, river sand of medium size of the “Kenitsy" deposit was used, as cementing agent - Portland cement of company “Mordovcement". The saponite-containing material extracted from the recycled water of the enrichment process of kimberlite ores was mechanically activated beforehand. Control samples of concrete and experimental (with the highly disperse additive) were prepared by standard methods. After aging for 28 days, the performance characteristics of the obtained samples (compressive strength, frost resistance and water impermeability) were determined. A highly dispersed saponite-containing material with an average particle size of 445 ± 40 nm and a specific surface of 50670 ± 10 m2 / kg was used as an additive to the concrete mixture. Determination of strength and frost-resistant characteristics showed a significant increase in these parameters in the prototypes. In addition, the introduction of a mineral supplement increases the brand's water resistance. Analysis of the microstructure of the concrete samples by scanning electron microscopy showed that (in contrast to control samples), hydrosilicates of the tobermorite group play the role of an additional binder. [ABSTRACT FROM AUTHOR]

The results of experimental research of hydration process of highly dispersed systems based on saponit-containing waste, extracted as the solid phase of the recycled water suspension kimberlite ore enrichment process of the diamond industry. Saponitcontaining sludge was dehydrated and subjected to mechanical activation on the planetary ball mill. Mechanical activation of raw material more than 60 minutes does not increase the specific surface area of samples was found. Specific surface area is achieves the maximum value of 50600 m2/kg. If we increasing the time of mechanical dispergation up to 120 minutes this parameter will be decrease due to agglomeration of particles. At the same time, average particle size of saponit-containing material will be in ranges from 445 to 517 nm. The x-ray analysis of the samples showed that the mechanical activation will help to increase the content of the active surface amorphous phase up to 40%. Adding of highly dispersed additive based on mechanic activated saponit-containing material to the composition of Portland cement after the interaction of this composition mixtures with water leads to the formation of submicrocrystals of the hydrosilicates from group of tobermorite. This fact was found by scanning electron microscopy methods. Record of absorption spectra in the infrared range of the samples was revealed of the fluctuations in the hydrosilicate groups, resulting in the following wave numbers 1440-1660 cm-1 and a broad band at 3300-3500 cm-1. This fact in agreement with the microstructural research. Thus, it is shown that the mechanoactivated saponite-containing material will be able to form the hydrosilicates of additional generation. The main conclusion of our work, based on our obtained results, allow us to use the saponite-containing waste as a potentially active mineral component in the binders compositions of hydration curing type. [ABSTRACT FROM AUTHOR]