Sprayed concrete and preparation method thereof

Abstract

The invention relates to the field of coal chemical industry solid waste resource utilization, and discloses sprayed concrete and a preparation method thereof. The invention provides a preparation method and proportion of an alkali-free, fluoride-free and chlorine-free accelerator for coal mine tunnel sprayed concrete by adopting a technology of directional excitation and graded utilization of gasified slag and utilizing the characteristics that key substances required by hydration reaction of the gasified slag in different particle size ranges are different in content and SiO2 is different in mineral phase. The early strength (especially 1d strength), the rebound rate, the bonding strength and other properties of the sprayed concrete of the coal mine tunnel are obviously improved. According to the present invention, the problems of guniting material cracking and reinforcing steel bar corrosion caused by the alkali-containing, fluorine-containing and chlorine-containing accelerator are effectively solved, the occurrence of the conditions of material later-stage structural shedding and aggravation of the alkali-aggregate reaction is avoided, and the in-situ modification of the gasification slag can absorb the moisture through the crystallization layer under the action of the electrostatic force so as to reduce the water absorption capacity of the gasification slag, free water in the system is prevented from being scrambled, and sufficient hydration is guaranteed.

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