| At present, common tunnel construction ventilation methods include natural, pressing, drawing, composite and gallery ventilation, while the gallery ventilation is specially suitable for super long tunnels that are constituted of parallel adits.The core of the gallery ventilation is that fan dampers are set at the doorways of tunnels, and the tunnels are used to ventilate as pipes. Besides, the method that auxiliary adits are used in super long tunnels will increase the distance of single head ventilation and reduce construction cost, so it is applied abroadly.Auxiliary adits can not be set in JinPing auxiliary tunnel, it is only excavated from the east and west, so the projet is one of the longest tunnel projects in China. Trackless transportation is applied in construction, so wind doorless gallery jet ventilation is applied in JinPing construction in order to safely and quickly construct and complete the project with high quality.Through sufficient investigation, numerical simulation and actual application, some research achievements are reached and can be listed as follows:(1) Design and calculation for super long tunnel construction ventilation with trackless transportationJin Ping auxiliary tunnel is buried deeply and very long, so the ventilation scheme is that pressing ventilation is applied at early stage and then wind doorless gallery jet ventilation; in addition, the scheme is calculated with relational theroy. Through validating the scheme with field project, the design satisfys the super long tunnel construction ventilation and achieve construction ventilation purpose that is safe, economic and reasonable, and JinPing auxiliary tunnel construction is completed; at the same time, the super long tunnel construction ventilation design is optimized.(2) Validate the ventilation scheme with CFD techonology and optimize the design for local settingThe flow and diffusion characteristics of gas in tunnel are studied with numerical simulation, the distributions of co at several times are reached with simulation and getting the conclusion that workers can construct safely in tunnel 8 minutes after blasting. It is approved that wind doorless gallery jet ventilation is suitable for JinPing auxiliary tunnel; meanwhile, the setting mode for jet fans and pipes is optimized in the tunnel.JinPing auxiliary tunnel project is the succeed ventilation example for super long tunnel with trackless transportation, it pionners the ventilation technology for super long tunnel.
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