高海拔特长隧道防灾疏散、救援技术研究

Research on the Evacuation and Rescue Technology for Disaster Prevention of High Altitude Extra- long Tunnel

研究目的:特长隧道的防灾疏散救援技术是铁路隧道运营安全的关键保障技术,青藏铁路西格二线关角隧道是我国首座长度突破30 km的高海拔铁路隧道,轨面高程超过3 300 m,也是目前世界上最长的高海拔隧道。隧道内的烟气分布与扩散规律不同于低海拔地区,人员的逃生速度受到极大限制,属世界隧道工程中首次遇到,在关角隧道深入研究高海拔特长隧道的防灾疏散救援技术,既是关角隧道工程建设的急需,也能为进一步规范、统一我国特长隧道建设防灾救援模式提供技术支持。研究结论:(1)烟气分布规律:在隧道顶部形成了夹带火焰的烟气顶棚射流,火灾初期烟气在隧道内呈现较好的烟气分层,随后上层烟气逐渐下沉,隧道内的自然风或活塞风会加速烟气的下沉;(2)通过疏散模拟证实,在长550 m的紧急救援站范围内设置12条疏散通道,横通道设1.7 m宽的逃生门能够满足疏散要求;(3)采用射流风机自安全隧道加压,采用均衡的竖井排烟技术,能够良好地控制烟气扩散和下沉,保障疏散安全;(4)配套的应急预案和设备控制技术也是必要的保障技术;(5)关角隧道的防灾疏散、救援技术为我国特长隧道防灾疏散救援提供了一种经典的设计模式,可为类似的隧道工程提供理论支持和工程案例。

Research purposes： The disaster prevention, evacuation and rescue technique of extra - long tunnels is the key technical guarantee for operational safety of railway tunnels. Guanjiao Tunnel on the second line of Xihing - Golmud Section of Qinghai - Tibet Railway is the first high - altitude railway tunnel exceeding 30 km in China, with rail top elevation over 3300 m. It is also the longest high - altitude tunnel in the world. The smoke distribution and propagation regularity in this tunnel are different from low -altitude tunnels. It is the first time in the tunnel projects worldwide to confront with the extreme limitation of evacuation speed. The in - depth research of disaster prevention, evacuation and rescue technique of Guanjiao Tunnel is an urgent need of the project itself, and also provides a technical support for further standardization of disaster prevention and rescue strategy for extra - long tunnels in our country. Research conclusions： （1） Smoke distribution regularity： ceiling jet with flame is formed at the tunnel roof; smoke stratification is well kept at the initial stage of fire, but later the smoke will graduall piston wind in the tunnel will facilitate the sinking of smoke. （2） According to the connections are set in the 550m emergency station and 1.7m wide escape door of requirement of evacuation. （3） Jet fans are used in the non - incident tunnel for y go down, and the natural wind or evacuation simulation, 12 cross- the cross connection can meet the over- pressure and uniform smoke extraction through shafts is adopted in order to keep good control of smoke propagation and sinking for safe evacuation. （4） Corresponding emergency plan and equipment control technique are also necessary security techniques. （5） Disaster prevention, evacuation and rescue techniques of Guanjiao Tunnel provide a classic design mode for extra - long tunnels in our country, and give theoretical support and serves as a reference for similar tunnel projects.