Optimization of regional advanced coal floor water hazard prevention and control technology and its application

In order to optimize the grouting process, improve the effect of the technology, and promote its application, this paper presents an investigation on the application of the regional advanced coal floor water hazard prevention and control technology in Huaibei mining area. The investigation shows that the pressure control in low pressure diffusion and medium pressure strengthening stages plays a major role in controlling the total grouting volume, which directly affects the limestone aquifer reformation. The prediction formula for grouting volume for strata with different karst fractures can provide guidance to the grouting engineering design. In addition, the horizontal layout method of double drill hole group inside and outside the working face is put forward to optimize the grouting technology and improve the utilization rate of drilling holes. To address the key technical issues of grouting pressure control and grout selection, the multi-source information identification method of fracture development and the stage-grouting pressure control model are established, in which the slurry types for different grouting stages are divided, and the classification threshold and design formula of grouting pressure are proposed, making the grouting pressure control efficiently and accurately. It is of great significance for the application and promotion of the regional advanced coal floor water hazard prevention and control technology.