Dabanshan tunnel

Dabanshan tunnel is located in the mountain crossing section of national highway 227 (Xining Zhangye) between 104KM and 109km. It is located in the northeast of Qinghai Tibet Plateau and the middle section of Dabanshan mountain in the east section of Qilian Mountains. The net width of the tunnel is 8.5m (including the lane width of 7m), the net height of the tunnel is 4.5m, the length of the tunnel is 1530m, the length of the lead wire is 2852m (including a 7 × 30m bridge), and the design driving speed is 45km / h The whole tunnel is composed of 1530m main tunnel and 1865m cold proof drainage tunnel under it, and 300m snow proof shed is set at the entrance and exit of main tunnel. The center elevation of the road surface at the entrance of the tunnel is 3792.75 meters. It is the road tunnel with the highest altitude in Asia and the second in the world. It is also a plateau highway tunnel built in permafrost.

Dabanshan tunnel

Dabanshan tunnel is located in the Dabanshan mountain crossing section of national highway 227 (Xining Zhangye) 104 km to 109 km, in the northeast of Qinghai Tibet Plateau, the eastern section of Qilian Mountains, and the middle section of Dabanshan mountain.

brief introduction

Daban mountain area is a strip-shaped medium high mountain area extending in the northwest direction. The mountain is steep and the route is tortuous. Generally, the altitude is 3650 ~ 3900m, the relative elevation difference is about 300m, and the altitude is 3780 ~ 3850m. There are permafrost distributed above the altitude, and the climate conditions are very bad.

Construction history

During the Eighth Five Year Plan period, the construction of Dabanshan tunnel was listed as a key project of highway construction by the Ministry of communications. In February 1993, Shaanxi highway survey and Design Institute carried out the survey and design, and invited public bidding for the first time in China, and the construction was undertaken by the first engineering office of the 16th Engineering Bureau of the Ministry of railways.

On August 18, 1995, Dabanshan tunnel was officially started. The total investment is 156 million yuan, of which 70% is allocated by the Ministry of communications and 30% is raised by Qinghai Provincial Department of communications. The tunnel is constructed according to the standard of class III Highway. The net width of the tunnel is 8.5m (including the lane width of 7m), the net height is 4.5m, the length of the tunnel is 1530m, the length of the lead wire is 2852m (including a 7 × 30m bridge), and the design driving speed is 45km / h. In order to avoid the long-term snow damage at Dabanshan pass, the whole tunnel is composed of 1530m main tunnel and 1865m cold proof drainage tunnel set parallel under it, and 300m cold proof drainage tunnel is set at the entrance and exit of the main tunnel Snow shed. The center elevation of the road surface at the entrance of Dabanshan tunnel is 3792.75 meters. It is the road tunnel with the highest altitude in Asia and the second highest in the world.

For the first time, the international f1d1c management mode was applied in the construction, and a number of advanced anti freezing and anti swelling measures such as flood control and drainage tunnel, drainage board, geotextile, thermal insulation layer, wind proof and thermal insulation door were adopted.

The main tunnel is lined with C25 single center circular concrete and supported by shotcrete. A composite waterproof layer composed of drainage board, non-woven geotextile and waterproof board is set between the support and the lining, and is connected with the cold proof discharge plume through vertical drainage drilling and longitudinal blind ditch. The lining surface is provided with a composite insulation layer composed of Pu dry process aluminum silicate fiberboard and FRP. Non pressure waterproof and drainage and active and passive combination of structural insulation. The tunnel is located in the joint zone of permafrost and seasonal frozen soil. It is located in the composite part of qiluhe mountain shaped two wings fold belt and Qinhuangdao Kunming East-West structural belt. The geological structure is abnormally developed, and the combination is complex. Three major faults run through it, and many water gushes. Therefore, in the construction, the regional geological structure is interpreted by remote sensing technology, the fracture structure, lithological characteristics and hydrogeological characteristics are investigated by comprehensive geophysical method, the geological characteristics of key parts are revealed and verified by drilling method, the appropriate meteorological observation station is established, the gas image data of tunnel entrance and exit are collected, the frozen soil distribution and frozen barrier characteristics are understood by exploratory wells, and the ground temperature is observed by deep holes In order to solve the problems of frozen soil forecast, wind blown snow damage and prevention and control plan. After three years and three months of hard construction, it was successfully completed on November 28, 1998. When the tunnel is completed, it can avoid the section with heavy snow on the top of Daban mountain, shorten the mileage by 5.2km, and make the Ning Zhang highway smooth in all seasons.

Awards

The tunnel won the excellent design award of the Ministry of communications in 2002, the first prize of quality engineering award of the Ministry of Railways in 2001 and the silver award of National Quality Engineering Award in 2002.

Address: National Highway 227, Datong Hui and Tu Autonomous County, Xining City, Qinghai Province

Longitude: 101.404297

Latitude: 37.347371

Chinese PinYin : Da Ban Shan Sui Dao