Isolated Overburden Grout Injection Technology Mining and Grouting Parameters Discussion and Redesign

Abstract

Abstract The "Three down" coal resource mining, ground subsidence management, and fly ash waste treatment are carried out using the Isolated Overburden Grout Injection Technology, which embodies the idea of green mining. The concurrent mining and grouting of bed-separation voids beneath key strata are intricately intertwined and subject to space and time constraints. Isolated Overburden Grout Injection Technology may be successfully analyzed using the large-deflection inclined thin plate mixed with the slurry model. Nevertheless, the diversity in stratigraphic parameters, including main roof and principal key strata (PKS), across various mines, as well as variations in design parameters such as working face dimensions, mining height, coal seam angle of inclination, mining speed, and grouting parameters like the number of grouting holes, start and finish times, and slurry consistency, ultimately contribute to discrepancies in outcomes such as PKS deflection and Bed-separation development, as well as the maximum subsidence and extent of the ground subsidence basin. To ensure the precise and efficient protection of village structures, the extraction of coal resources, and the proper disposal of fly ash waste, it is imperative to conduct a comprehensive analysis of the impact of each parameter of the model. This analysis will help elucidate the mining and grouting process and facilitate the rational design of the relevant parameters. This paper categorizes and discusses the impact of each parameter on the outcomes, using the case study of the 7221 work face grouting operations in Huaibei, Anhui Province, China. In order to fulfill the protection needs of the Gaochangying and Houlou Gaojia villages, modifications were made to the mining and grouting sections' parameters. These modifications evaluated the potential benefits of increasing the original design of coal seam resources and implementing fly ash backfill.