由于城市公路交通隧道能够疏散城市地面交通、减少道路用地,其建设数量和规模随着城市的发展日益增加。城市交通隧道最主要的灾害是火灾,本文在分析城市交通隧道相对于山区公路隧道在隧道结构、车流密度、火灾规律等方面特点的基础上,对其消防难点以及关键技术进行探讨,并指出了城市交通隧道火灾安全未来研究的方向。研究表明:国内城市交通隧道主要采用纵向通风模式,坡度、出入口、竖井设置对控制烟气的临界风速影响远大于非城市公路隧道。采用数值模拟技术结合局部现场试验是研究隧道火灾烟气扩散合理可行的手段,开展隧道火灾羽流复杂的时空行为基础研究以及发展场-网模拟技术将有益于城市交通隧道通风、防排烟设计和火灾安全水平的提高。
With the development of city,the quantity and scale of urban traffic tunnel are increasing because urban traffic tunnel can cut down the city ground traffic and reduce the land use for road.Fire is the most important disaster of urban traffic tunnel.The specialties in tunnel structure,traffic flow density and fire character of urban traffic tunnel are analyzed by comparing with those for non-city road tunnel.The difficulties and key technology for fire safety engineering are discussed and future research directions for fire safety are pointed out.The following conclusions can be drown that longitudinal ventilation mode is mainly adopted in current urban traffic tunnels in China.The influences of urban traffic tunnel slope,the positions of tunnel portal,entrance-exit and shaft on critical velocity for smoke control are more important than that for non-city traffic tunnel.Combing numerical simulation method with a local full-scale test is a reasonable and reliable technology for studying smoke propagation in urban traffic tunnel.The fundamental researches on complex time-space behavior of tunnel fire plume and development of hybrid field-network simulation method would be benefit for designing ventilation,smoke control system and enhancing the fire safety level of urban traffic tunnel.