Study On Key Technique Of Construction Ventilation For Exta-Long Highway Tunnel At High Altitude On Queer Mountain

In recent years, with the accelerating development of highway construction in our country, the scale and quantity of highway tunnel construction have also obtained rapid development.In China, the highway network of the east and the central area has already been basically covered most of cities, while that of the west still lag behind. In order to guarantee the economic development in western China, our country is speeding up the highway construction plan of the west. Since there are numerous mountains with a relatively high altitude in western region, the number of existing high-altitude tunnel and that under construction is gradually increasing. The major problem faced in the process of tunnel construction is that the builders are easily to have altitude stress because the higher the altitude is,the lower the air pressure and oxygen content, then the efficiency of construction will be affected.The tunnel of Que’er Mountain,the state road 317 line, is 7048 meters in length, and its portal is about 4380 meters in height. In order to acquire the key technical index like the ventilation standard of tunnels in high-altitude regions, and provide the design basis for the plan of ventilation system of high-altitude tunnel construction, relevant researches on the control standard of CO concentration in plateau section, the discharge capacity of machine, the blower performance and the air leakage rate of air ducts have been carried out according to the extremely long highway tunnel of high altitude in Chola mountain, establishing a complete set of ventilation design standard in high-altitude construction. The major research works and results of this paper are following four respects:1.By analyzing the mechanism of CO poisoning to human body, based on the theory of CFK equation model,and applying the MATLAB to analyze, calculate and research the CO control standard, the CO control standard in high-altitude can finally be acquired.2.Based on standards, the exhaust emissions testing data of various vehicles was obtained through investigation to analyze the modified value of the CO emission and smog emission amount,and finally revise the current standards3.According to Fan similarity law, theoretical deduction was made to revise the the air quantity, wind pressure, and the efficiency of fan in the high-altitude ares, and the Fluent software was used to fan modeling. The performance difference between the fan in plain and high-altitude region was analyzed by changing the the structure of fan and the working environment, and fan structure optimization was conducted.4. The study of the theory of duct air leakage were calculated and analyzed on the air leakage rate of duct in high-altitude areas by means of theoretical deduction, and use the modeling of Fluent software to conduct simulation analysis in an effort to correct the air leakage rate of duct in high-altitude areas.The study and revision of each parameter in the ventilation design of construction provide technology security for the ventilation technology of tunnel construction in Chola mountain, ensure the tunnel constructor’s personal safety, offer technology support for the efficient, fast and safe construction of the tunnel in Chola mountain, and provide a valuable reference for other similar ventilation technology of high-altitude tunnel construction.