为解决超大断面高速公路隧道的火灾排烟及疏散救援难题，以深圳机荷高速双层盾构隧道为依托，采用FDS数值模拟方法对隧道标准断面和分叉断面处火灾排烟特性、温度场和能见度的分布规律进行研究，确定火灾工况下各个位置能见度和温度随时间的变化以及烟气扩散情况，建议隧道内应控制纵向风速不小于3 m/s；结合高速公路隧道火灾的起因和特点，开展高速公路隧道火灾事故应急救援综合研究，运用仿真模拟法对多组楼梯参数取值情况下共计6种疏散工况进行计算，确定横通道间距为250 m、楼梯间距为80 m时，可满足人员安全疏散要求；最后，提出超大断面双层高速公路隧道火灾应急救援体系，并针对机荷高速双层盾构隧道给出救援疏散路线以及各位置发生火灾时的排烟疏散策略。

A Shenzhen Jihe highspeed doubledeck shield tunnel case study is being conducted to realize smoke extraction, evacuation, and rescue in a superlarge crosssection highway tunnel. Then, under varied fire conditions, the smoke extraction characteristics, temperature field, and visibility distribution at the conventional and bifurcated crosssection of the tunnel are investigated with FDS numerical simulation method. It is recommended that the longitudinal wind speed of the tunnel should be kept within 3 m/s. A comprehensive study on the emergency rescue of highway tunnel fire accidents is conducted based on the causes and characteristics of a highway tunnel fire. Furthermore, a simulation method is used to calculate six evacuation conditions in the case of multiple groups of stair parameters, and it is established that the safety evacuation requirements can be met when the crosspassage spacing is 250 m and the stair spacing is 80 m. Finally, the fire emergency rescue strategy system of the superlarge crosssection doubledeck highway tunnel is proposed, and the rescue evacuation route and smoke extraction strategy for the Jihe highspeed doubledeck shield tunnel are put forward.