Main line of Jinyuding Tunnel of Long-Long Railway is 4425.11 meters long.  geological conditions of the section where the tunnel is located are complex. Shallowest depth is 8 meters. Surrounding rock of whole tunnel is more than 1,400 meters long with faults, many broken surrounding rocks, poor stability, open fissures, water-conducting faults, and connections with surface water.

China Railway Nanchang Bureau Group Co., Ltd. and Fujian Railway Construction Headquarters organized construction unit China Railway 24th Bureau to incorporate advanced geological forecasting.

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