An overview of integrated surface subsidence-reducing technology in mining areas of China

Abstract

Surface subsidence-reducing technologies are currently being used within coal mining areas in China according to the requirements of harmonious development of coal mining and environment protection. Here, these technologies were overviewed, including the strip mining, backfill mining, overburden-separation grouting and vacant space grouting of caving rocks, and the problems in their applications were analyzed. It is proposed that integrated surface subsidence-reducing technology can rapidly develop in China, while aiding the safe development of coal mining areas. The theories and application principles of five types of integrated surface subsidence-reducing technologies were introduced, including strip mining combined with overburden-separation grouting, strip mining combined with vacant space grouting of caving rocks, strip mining combined with overburden-separation grouting and vacant space grouting of caving rocks, overburden-separation grouting combined with vacant space grouting of caving rocks, and strip mining combined with backfill mining. Also an engineering application of strip mining combined with backfill mining in Daizhuang coal mine was introduced, and the application results show that the surface subsidence coefficient was 0.08 and more than 48.8 Mt of coal were recovered, which confirmed that integrated technologies could effectively reduce surface subsidence and waste of coal resources. Finally, the prospects for the development of integrated technologies were discussed, and the shortcomings of theory, effective evaluations and practical applications of these integrated technologies were examined.