Urban traffic link tunnels (UTLT) have a complex design and are a significant fire hazard. Due to the circular nature of the tunnels, smoke can easily spread through the tunnel during a fire and form a circulation loop, severely hampering safe evacuation and rescue. In this paper, the 2.8km long UTLT in Sichuan, China's Dayuan central business district (CBD) was the study subject. Fire dynamics and similarity theory were employed to perform theoretical calculations and numerical simulations targeting four different mechanical smoke extraction methods under typical fire conditions. Smoke movement was quantitatively analyzed, thus determining which of the four plans was the optimal smoke control technique: semi-transverse ventilation combined with sinking-courtyard air compensation, with ventilation beginning in the fire zone and the two flanking smoke control zones at a rate of 20 ventilations/hour. Our result provides a theoretical basis for designing and running a smoke control system in relevant projects at home and abroad, and serves as both a theoretical and a constructive practical ground for formulating regulations related to UTLT.
Study on Smoke Control of Wuhan CBD Urban Traffic Link Tunnel
