关键词: 立井, 多层承压含水层, 瞬变电磁法, 工作面预注浆, 壁后注浆

Abstract: In view of the outstanding safety risks such as water inrush，well flooding and surrounding rock instability during the construction of the vertical shaft crossing the multi-layer confined aquifer，based on the auxiliary shaft of an iron mine，the theoretical analysis and engineering practice are combined. Based on the coupling theory of hydrodynamics and grouting dynamics，the theoretical framework of "pre⁃ cise identification of geophysical prospecting-high pressure grouting plugging of working face-grouting fill⁃ ing behind wal" is constructed，and the technical connection logic and synergistic mechanism of each pro⁃ cess stage are clarified. The transient electromagnetic method combined with the whole space and whole ar⁃ ea apparent resistivity inversion algorithm is used to realize the spatial positioning of multi-layer confined aquifer and high-risk water inrush channel. The comprehensive coincidence degree between geophysical low resistance anomaly and drilling water outlet point is 91.7%. On this basis，the pre-grouting of multi�stage working face is carried out by using the matching technology of filter layer-slurry stopping pad and the dynamic control technology of grouting parameters，and the secondary reinforcement of micro-cracks in shaft wall is completed by grouting behind the wall. The engineering practice results show that 78.27 m3 /h maximum single hole water inflow of the working face is effectively controlled，and the water inflow of the working face is stable below 4 m3 / h after the completion of each grouting section. After the treatment of grouting behind wall，the amount of water leaching from the wall is reduced from the maximum 6.13 m3 less than 1.5 m3 /h. The technical system realizes the fine treatment of the main water inrush channel plug⁃ ging and the micro-fracture leakage of the borehole wall，and forms a double-layer protective structure of "main channel plugging+micro-fracture filling" which can provide technical reference for the safe and effi⁃ cient construction of deep shafts under complex hydrogeological conditions.

Key words: shaft, multi-layer confined aquifers, transient electromagnetic method, working face pre-grouting, grouting behind wall