Abstract: In response to the issue of surface subsidence encountered during the excavation of shallow-buried soft rock sections in mountain tunnels,this study conducts theoretical calculations and numerical simulations to analyze the surface subsidence in the Xinwu Tunnel’s shallow-buried sections,examining the effectiveness of various reinforcement methods.The applicability of high-pressure jet grouting piles in controlling surface subsidence is demonstrated through combination with field experiments and monitoring analysis.This research provides a reference for surface subsidence control in similar geological settings of mountain tunnels.The study reveals that as the tunnel face advances,the pattern of surface subsidence in the shallow-buried sections resembles a funnel shape,with maximum settlement at the center decreasing gradually towards the sides.The extent of influence due to tunnel excavation extends approximately 40 meters laterally (6 to 7 times the tunnel’s radius) and 12 meters axially (2 times the tunnel’s radius).The control rates of surface subsidence after reinforcement with high-pressure jet grouting piles,cement mixing piles,and in-tunnel grouting are 74.2%,53.52%,and 41.2% respectively,indicating that high-pressure jet grouting piles significantly outperform other methods in reinforcing the surrounding rock and controlling settlement.The trends of subsidence changes from field monitoring are generally consistent with those from numerical simulations.Following reinforcement with high-pressure jet grouting piles,the maximum recorded surface subsidence is significantly reduced to just 27.88mm,demonstrating that high-pressure jet grouting piles are effective in controlling surface subsidence in shallow-buried soft rock sections of mountain tunnels.