Abstract: In this study, the smoke flow at the entrance and exit of the tunnel and the BRE plume overflow model inside the combustion chamber are used for analogy analysis. By drawing on the calculation methods of some of its parameters, a set of direct fire wind pressure calculation methods based on J TG/TD 70/2-02-2014 Detailed Rules for the Design of Highway Tunnel Ventilation are obtained when the maximum slope section of the tunnel is located at the entrance and exit of the tunnel. Based on a certain project, the theoretical calculation results are compared with the numerical simulation results, and it is found that they are relatively close.

Key words: BRE plume overflow model, fire wind pressure, theoretical calculation