中文摘要：

通过在云南昆明-石林高速公路阳宗隧道内的现场模拟火灾试验，对不同纵向通风速率下公路隧道内火灾烟气温度及层化高度沿隧道的分布特征进行了研究。结果表明：拱顶下方烟气温度沿隧道呈幂指数分布；纵向通风速度对烟气层高度沿隧道的分布有重大影响，纵向风速较小时，烟气可以在隧道上部空间维持较好的层化结构，不会影响火灾发生时人员的安全疏散，而较大的纵向风速将导致烟气层高度沿隧道迅速降到地面，对火灾发生时的人员疏散造成威胁。

英文摘要：

Field fire simulation experiments were conducted in the Yangzong Tunnel of KunmingShilin freeway in Yunnan Province of China. Characteristics of smoke layer temperature and layer stratification height distribution along the tunnel were measured at normal ventilation speed, natural ventilation speed and smoke exhaust ventilation speed conditions. Results show that the smoke temperature below the ceiling along the tunnel falls into exponential distribution and the longitudinal ventilation speeds influence the smoke layer height distribution along the tunnel largely. When longitudinal wind speed is small, the smoke layer can be remained at the upper part of the tunnel and does little influence for the human evacuation; while smoke would be blown to the floor level and be dangerous for human evacuation when ventilation speed is relative large.