With the surge of extra-long tunnels, the vertical shafts are widely used to shorten the construction period and become a part of the ventilation system during the operation period. Because of the towering mountains, the depth of vertical shafts is usually about 100 m or more, which is quite different from those of urban road tunnels. As a result, it is indispensable to set up perfect smoke extraction strategies, including exhaust velocity and supply velocity, featuring longitudinal ventilation system with vertical shafts to reduce the great loss during tunnel fire. To control smoke better, 1: 4.8 reduced-scale tests were carried out. In addition, a series of full-scale numerical simulations were established, using FDS, to refine the supply velocity of three HRRs of three fire source locations. From this study, some conclusions were drawn: (1) Without ventilation system, the temperature at the junction of the main tunnel and shaft is higher, because of more smoke vents and stronger stack effect provided by vertical shafts. (2) Due to the stack effect of vertical shafts, the exhaust velocity is smaller than the supply velocity under a bigger HRR. (3) The HRRs and the fire locations made no difference to the exhaust velocity which is 3 m/s. When the fire source is located at the exhaust region and middle region, the respective supply velocity is in the range of 3 ~ 4 m/s and 4 ~ 6 m/s. When the fire source is situated in the supply region, the supply velocity of 6 m/s is suitable for all three HRRs. (4) The fitting formulas of the exhaust region and middle region are expressed. The results in this work will provide references for tunnel designers and engineers to devise smoke extraction strategies during tunnel fires.

随着特长隧道的涌现，竖井被广泛采用，以缩短施工周期，成为运营期通风系统的一部分。由于高山耸立，竖井的深度通常在100m左右甚至更深，这与城市道路隧道有很大的不同。因此，必须制定完善的排烟策略，包括排烟速度和送风速度，采用竖井纵向通风系统，以减少隧道火灾中的巨大损失。为了更好地控制烟雾，进行了 1:4.8 的缩小规模测试。此外，还使用 ​​FDS 建立了一系列全尺寸数值模拟，以细化三个火源位置的三个 HRR 的供应速度。通过这项研究，得出了一些结论：(1) 没有通风系统，主隧道与竖井连接处的温度较高，因为竖井提供了更多的排烟口和更强的烟囱效应。(2) 由于竖井的烟囱效应，在较大的HRR下排气速度小于供给速度。(3) HRRs 和火灾位置对3 m/s 的排气速度没有影响。当火源位于排气区和中间区时，各自的供给速度在3～4m/s和4～6m/s范围内。当火源位于供应区域时，6 m/s 的供应速度适用于所有三个 HRR。(4) 给出了排气区和中间区的拟合公式。