Study On The Method For Ventilation Of The Long Twin-tube Roadway Tunnel Network

Because of the shortages of resources, longitudinal ventilation is much popular for it can meet the requirements of construction and operation, and can ensure the safety. Shaft ventilation systems have been widely applied in highway tunnels in the world. However, the tunnel shafts cause a even bigger cost from construction and operation, and then a variety of ventilation solutions in many countries have emerged to strike a balance between the economic and security in recent years.Based on the renovation project of Jiulingshan Tunnel in Jiangxi Province, the article has made some attempt under below around the twin-tube network:1. It's changed the traditional idea of ventilation in perpendicular space into horizontal plane. After researching on the characteristics of the method for ventilating twin-tube roadway tunnel network, the author is attempt to fully use the imbalance of wind pressure, which caused by different tunnel gradients, and reduce tunnel construction and operating costs after the establishment of their connections, and then gives the specific design process and calculating methods.2. For the convenience of calculation, the author has combined the method of twin-tube ventilation network theory and has developed a program using VB language and Matlab components based on the Hardy-Cross algorithm. The program can compare not only from horizontal ventilation holes but also from different ventilation types and then, select the better. Using the program, the article has calculated two ventilation types of Jiulingshan Tunnel and has given a better choice.3. Tunnel ventilation strategy under fire conditions are given, and tunnel ventilation strategy at different location of the disaster of the fan operation scheme is provided. At the same time we should improve tunnel disaster monitoring method. The conclusion is that we'd increase refuge chambers in the twin-tubes after the analysis of specific accidents.