Research Progress of Concrete Preparation Based on Solid Waste Properties of Coal Gangue

Coal gangue (CG) is one of the most frequent solid wastes in the world, and it poses a severe hazard to both human society and natural ecosystems. In light of the progressive increase in environmental awareness and the unavoidable trend of the requirements of a sustainable development plan, how to efficiently use these vast quantities of CG has become an important subject in China. Concrete aggregate, which can not only solve environmental pollution but also compensate for the scarcity of natural gravel and sand resources, is the most cost-effective and eco-friendly way to utilize CG resources in accordance with the strategic requirements of green and sustainable development. However, how to deal with the preparation of high-quality gangue aggregate needs to be targeted research; blindly using gangue for concrete may bring some safety hazards. This requires that based on the source, distribution, storage, chemical composition, mineral composition of the gangue and the problems in the utilization process, efforts are made to open up the key routes of gangue concrete utilization, and to provide theoretical guidance for the high-value and environmentally friendly utilization of the CG. This paper summarizes the CG aggregate characteristics and its impact on concrete performance, discusses the technical means to improve the performance of CG aggregate concrete, and analyzes if the current CG aggregate in the concrete application of the problem still exists, with a view to gradually realize the CG of low-energy consumption bulk utilization. The popularization and application of CG aggregate will accelerate the solution of the environmental pollution problem it brings, and can to a certain extent alleviate the current situation in that the supply of natural sand and gravel resources is insufficient to meet the demand; the sustainable development of today’s research on CG aggregate for concrete has important environmental and economic significance.