Research On Technique Of Operation Ventilation And Disaster Prevention In Urban Underwater Tunnel

Urban underwater tunnel with the dual character of both urban tunnel and underwater tunnel has high requirements in the safety of operation and environmental protection. Tunnel's operation safety and environmental protection are to develop the key factors which must be taken into account when working out the ventilation programs for urban underwater tunnel. Currently, Chinese construction of the tunnel technology has reached or come close to the world's advanced technologies, but the operation management of the tunnel is still very backward in many places yet to be resolved. Tunnel construction of large-scale and operation management of the relatively backward will inevitably lead to the deterioration of the environment and the increase in insecurity in the tunnel, so it is necessary to make special research on The Urban Underwater Tunnel.Firstly, the highway tunnel ventilation standards which at home and abroad were studied in this paper. Based on the domestic practical situation, according to the constraints under ventilation standards of reference to the relevant standards abroad tunnel ventilation standards were identified. After another study in detail of the practical situation and variation rules, the tunnel under the mechanical vehicle emissions were decided. Besides, the ventilation standards based on the above, as well as mechanical vehicle emissions, in the light of the practical situation of PIARC as ventilation design thinking Ventilation Schemes have been selected.Secondly, two of the tunnel Ventilation Schemes, that is say, removing the contaminated gas though the tunnel entrance and shaft have been in the numerical simulation.That the zone (200×165×60m) outside of the tunnel has been carried on the numerical simulation under different wind conditions to studay the concention of the pollution air and in the light of local environmental quality standards for environmental evaluation. Also the plume rise height from the shaft was calculated to determine the plume rise height.Finally, in accordance with the equivalent under different fire spread smoke, temperature distribution was studied and the different fire under the equivalent speed of the spread of smoke and critical veolicity was identified. In the case of large slope for tunnel, the smoke spread was also studied.In summary, this paper has discussed both the operation safety and environmental protection of The Urban Underwater Tunnel .It has made a detailed study in the choice of Ventilation Schemes and pollutants as well as the proliferation of fire smoke spread of the condition and found some things of a regular pattern which provides The Urban Underwater Tunnel ventilation system design and tunnel's operation with a good reference value.