Abstract: The construction of large-diameter rescue holes in mines faces challenges such as tight timelines,complex geological conditions,and high requirements for trajectory accuracy. To meet the needs for efficient and reliable hole formation under complex and variable strata conditions, based on an analysis of the technical characteristics and applicable conditions of large-diameter rescue hole drilling, the aim is to establish a classification system for large-diameter rescue hole drilling technology, develop a process adaptability optimization method centered around "stratum-process-equipment", and focus on researching key technical challenges and engineering application effects of gas-liquid dual-circulation drilling technology. For key technologies such as roller cone multi-stage reaming, PDC multi-stage reaming,airlift reverse circulation,pneumatic down-the-hole hammer, and gas-liquid dual-circulation, systematic sorting and comparison are conducted in terms of rock-breaking mechanism, circulating slag removal method, supporting drilling tools,and process parameters. The performance of each process under different lithologies, hole diameters, and hole depths is discussed, and its efficiency bottlenecks and risks are analyzed. On this basis, a combination of theoretical analysis and numerical simulation is used to study the rock stress distribution characteristics and crack propagation laws under different reaming ratios, analyze the evolution stages of multiphase flow field at the hole bottom and rock debris migration characteristics, and reveal the influence mechanism of hole bottom back pressure on the impact performance of down-the-hole hammer. Finally, a pilot test of gas-liquid dual-circulation drilling is conducted to test the sealing reliability and drilling efficiency of the three-wall drilling tool system and airtight down-the-hole hammer. Conventional process comparisons show that for stable medium to hard strata, PDC multi-stage reaming has significant efficiency advantages. After adopting a mud-proof design, the average drilling speed for a Φ830 mm hole diameter can reach 5.85 m/h. For hard, fractured, or water-bearing strata,pneumatic down-the-hole hammer technology has more advantages. Among them, the cluster-type down-the-hole hammer reverse circulation drilling, with the joint sealing process guarantee at the hole mouth-hole bottom,achieves an average mechanical drilling speed of 3.13 m/h and thorough slag removal.Rock-breaking mechanism research shows that the rock-breaking efficiency is highest when the reaming ratio k=3; the flow field at the hole bottom can be divided into an acceleration stage(0-2 s)and a stable circulation stage(2-8 s); the impact power and impact frequency of the down-the-hole hammer decrease with increasing back pressure. The pilot test shows that the sealing of the supporting drilling tools for gas-liquid dual-circulation drilling is reliable, and the average mechanical drilling speed reaches 3.94 m/h under a hole diameter of Ф350 mm and a hole depth of 200 m. Gas-liquid dual-circulation drilling utilizes an independent gas circuit to drive the downhole hammer and an independent liquid circuit to carry debris and protect the wall, ensuring that the efficiency of the downhole hammer is not affected by hole depth or water inrush. This technique has significant advantages in deep and complex strata, and is an important technical direction for enhancing the drilling capability of rescue holes.