Performance Based Application Of Water Mist Fire Suppression System In The Cable Tunnel

Recent trends in civil construction and the growing needs for electronic plant have led to the use of large numbers of cable tunnels. However the cable tunnel is often free of person which led hard to aware of the occurrence of fire. And the worse case is that the fires in the cable tunnel spread very quickly because of the confined environments, and common fire fighting measures may be limited. These developments have resulted in additional awareness of the fire hazard for the cable tunnel and promotion for new fire suppression systems which may result in improved fire safety of cable tunnel.Water mist, as a substitute of Halon, has valuably potential applications in the fire protection of cable tunnel. However, the design of Water mist system cannot follow the general rules due to the complicated fire suppression mechanisms. And the lack of general code of water mist fire suppression systems in China further hamper the application of water mist.In this thesis, an optimization design and evaluation method of water mist fire suppression system has been established via employing the concepts of performance based design for the application of water mist protection system in the cable tunnel. Firstly, Fire scenarios are determined by possible fire developments based on the actual fireproofing purpose. The fire and smoke hazard in the cable tunnel for various fire scenarios are then evaluated using computer simulation. On the other hand, Full scale fire extinguishing tests are conducted for validation. Results show that this method provides a reasonable tool to unify the effectiveness and economics of water mist system design.The present thesis firstly review the relate research work on cable tunnel. The fire characteristics of the cable and cable tunnel are then well documented. The general principles of performance based design are introduced to provide the concepts of performance based design for the application of water mist protection system. Fire hazard of hazard in the cable tunnel for various fire scenarios are then evaluated using FDS model. Full scale fire extinguishing tests for water mist protection of PUDONG cable tunnel are then conducted for optimization design validation. In the finality, the main research results are summarized and the problems requiring further studies are discussed.