Research On Ventilation Technology Of Super Long Underwater Tunnel

With the length and scale of underwater tunnel increasing, tunnel ventilation becomes one of the important control factors of the triumphant building and safe operation of underwater tunnel. Along with the development of economy and the improvement of people’s living, people put higher request forward the safety and environmental protection of super long or large tunnel. Because the functions, geographic location, environmental needs of underwater tunnel are different from mountain tunnel, there is no any standards specification of tunnel ventilation on urban tunnel and underwater tunnel in our country.In the meantime, there are less research and experience about underwater tunnel ventilation. So it is necessary to develop the special studies for them,that will provide technical storage for tunnel safety,economic,reasonable and environmental operation and management,and avoid the risk and system failure in construction stage, design stage and operation stage.Through the method of documentary data and engineering practices analysis, this paper put forward the concentration limits for air pollutants of tunnel ventilation, aiming at the characteristics of super long underwater tunnel and the present situation of China’s economic and technological developing level. Carrying out the research on the key technology of two shafts blowing and exhausting longitudinal ventilation mode by physical model testing of large scale,that is air distribution in the short air duct of ventilation shafts bottom, this paper suggests requirements about the minimum value of interporosity flow velocity and air volume ratio, which is to provide valuable references for ventilation system, design.At last,the paper studies on the air purification treatment technology of the air pollution in tunnel, and carries on pilot plant experiment in the actual project,that can offer technological support to prevent air pollution by air pollutants of tunnel in tunnel area.But above all, the thesis analyzed the concentration limits for air pollutants of tunnel ventilation, air distribution and air purification treatment technology.The thesis raises some technical proposal that ensure the rationality and validity on operation of the tunnel ventilation system, based on the development tendency, experiment phenomena and analysis results, which will provide references for the design and operations management of tunnel ventilation system of super long underwater tunnel,and has good application value.