对隧道汽车火灾进行分析认为,汽油等液态燃烧物是控制隧道车辆火灾的关键因素。针对汽油等液态燃烧物的燃烧,设计多孔结构的OGFC混合料,进行不同空隙率OGFC-13混合料的汽油模拟燃烧试验,以武汉市过江隧道为依托背景设计隧道路面结构,并通过室内试验与材料成本计算进行技术经济评价。研究结果表明,多孔结构可以迅速排逸路表的液态燃烧物,阻止火势蔓延。空隙率对OGFC混合料的防火阻燃性能具有重要影响,随着空隙率增大,燃烧时间缩短,逃逸汽油量增加,温度降度。但当空隙率达到20%以上时,孔隙过大,燃油蒸气扩散至路表,导致防火阻燃性能降低,18%~20%为OGFC-13防火阻燃性能最优的空隙率范围。以OGFC-13为面层设计隧道防火路面,不但路用性能优于SM A-13面层,而且节约了材料成本,值得推广应用。
By analyzing the car-fire in road tunnel, it is concluded the liquid fuel (gasoline) is the key to retard fire. For the flame of liquid fuel, the porous asphalt mixtures is designed and simulation fire tests are conducted with different air-voids. According to Wuhan Yangtze River Crossing Tunnel, the pavement is designed, and corresponding indoor testes and economic analysis are carried out. The results of tests show that the porous-grain structure could drain the gasoline on the road surface and retard spreading of fire. Air void evidently influence the fire-retardant performance of Open-graded Asphalt Friction Course (OGFC). With the enlarging of air-void, the fire time is shortened, and draining-gasoline increased and temperature fell off. But once the air-void exceeded 20%, the gasoline stream diffuses to the road surface and the fire-retardant performance is depressed, so the optimal air-void range is 18%-20%. On the other hand, the fire-retardant pavement used OGFC mixtures not only own excellent road performance, but also save cost.