The article discusses the possibility of using coal waste for the preparation of mine concrete. As a result of the research, scientific and prac- tical results were obtained. It has been experimentally proved that when a small fraction of coal, which is a waste of coal mining, is added to mine concrete, the strength of concrete decreases, but with a certain ratio of this strength it is sufficient to ensure the required properties. A series of experi- ments was carried out with the addition of liquid glass to the concrete to control the setting time of the mixture. The properties of coal wastes were determined and the possibility of their use in mine concrete was investigated. It has been established that the introduction of a fine fraction of coal in the optimum quantity into the composition of mine concrete is possible without reducing technological parameters.

The possibility of using coal mining waste in mine concrete mixing is considered in the article. As a result of the research, scientific and practical results have been obtained that make it possible to evaluate the strength properties of mine concrete, depending on the content of coal dust particles - the waste of mining - in it. It has been experimentally proven that when a fine fraction of coal is added to mine concrete, the strength of concrete decreases at a certain ratio, but this strength is sufficient to ensure the required properties. As a result of the experiments, samples of concrete for mine construction were manufactured, into which a fine fraction of coal - coal dust - was added in various ratios. A series of mine concrete tests was carried out to determine its physical and mechanical properties; the optimal composition was determined, which provides process and strength performance of the mixture. The conclusions have been drawn about the quantitative content of a fine fraction of coal in mine concrete, which make it possible to maintain process performance of the mixture and the strength of structures.

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The issues of the modification of a binder in structural cement concrete for mine and underground construction with wastes of chemical enterprises are considered in the article. Hundreds of tons of waste are generated annually at chemical enterprises of the Russian Federation, polluting the environment and requiring their disposal. The performed studies deal with the improvement of physical and mechanical properties of a cement binder with a dispersed manganese sludge modifier, which is a waste product of ammonia or methanol production, for its use in mine and underground construction. As a result of the studies performed, it was found that the addition of dispersed sludge with manganese oxide in an amount of 4% of the cement mass to a cement binder leads to the activation of the cement hydration process, while the rate of development of the plastic strength of the cement stone structure increases, the period of its structure formation reduces and the compressive cement stone strength increases by 17-18%, which makes it possible to reduce the cement content in structural concrete by 8.8-10.0% while maintaining its strength, reducing the cost of mine and underground structures and, as a result, reducing the cost of mining.