Study on Fire Smoke Characteristic in Double-tube Road Tunnel with Complementary Ventilation System

Complementary ventilation is a new and energy-saving mode put forward recently. In order to address safety concerns under fire situation, the fire simulation software FDS has been adopted to build a tunnel model with two tubes. The fire smoke spread rule, temperature field and visibility distribution in two tubes after fire are analysed. Results show that before closing the air valve in connect duct, a small volume of smoke spreads to the adjacent tube. Judging from temperature and visibility, the influence is limited; after closing the air valve, the adjacent tube is no longer affected by the fire tube. According to the personnel safety standards stated in the PIARC2005 Research Report, the complementary ventilation system can meet the requirements of tunnel safety operation in case of fire. Finally, a wet resonance grille dust removal device is proposed to prevent smoke from flowing into the adjacent tube.