Abstract:

Zhongnanshan extralong highway tunnel crossing Qinling Mountain is a largescale project that has complex ventilation system. In order to properly determine the ventilation scheme and to save the ventilation cost, the estimation of the ventilation effect of nonmechanical ventilation is very important. Based on the analysis of the monitoring data achieved from field monitoring of the natural air speed, traffic piston air speed and traffic volume, the authors conclude that the high natural air speed occurs from 11:00 to 13:00 with the maximal speed reaching 2.576m/s; the rush hour in the east tube and in the west tube has almost no change; the  high air speed in the west tube occurs almost at the same time as the rush hours while the high air speed and rush hour in the east tube does not match and the air speed is nearly stable in the east tube.

Key words:  extralong road tunnelventilation effectfield test, traffic volume;natural air speedpiston air