How long is the longest tunnel in Asia?

The longest highway tunnel in Asia - the Qinling Extra Long Tunnel, with a total length of 18 kilometers

Qinling Tunnel: Line I is 18,460 meters; Line II is 18,456 meters.

The Qinling Tunnel was once the longest railway tunnel in China. It is located between Qingcha Station and Yingpan Station of the Xi (An) (An) Kang Railway. It consists of two basically parallel single-line tunnels with a spacing between two lines. The total length of the Line I tunnel is 18,460 meters; the total length of the Line II tunnel is 18,456 meters. The lithology of the area where the tunnel passes is mainly mixed gneiss, mixed granite, and mixed granite containing green minerals; the tunnel body passes through 13 faults, among which the largest faults include regional faults such as F, F, and F. The elevation of the north entrance of the tunnel is about 870 meters, the elevation of the south entrance is about 1025 meters, and the height difference between the two ends of the tunnel is about 155 meters.

The location map of the Qinling Tunnel photographed by satellite. The longitudinal slopes of Line I and Line II tunnels are basically the same. After entering the tunnel from the Xi'an end, the range is 11‰ uphill for about 14.7 kilometers, and then 3.2 kilometers and 3‰ downhill. Get out of the hole. The maximum burial depth of the tunnel is about 1,600 meters, and the section with a burial depth of more than 1,000 meters is about 3.8 kilometers long. The geological conditions of the section where the Qinling Tunnel passes are very complex. After testing by various means, unfavorable geological disasters such as high ground stress, rock bursts, ground pads, water inflows from fault zones, and surrounding rock instability occurred during construction. The engineering construction task is very arduous.

Qinling Tunnel: At present, China's railways and highways have passed through the Qinling Mountains seven times

The first time was the Baocheng Railway winding through the Qinling Mountains in the 1950s;

The second time is to build the Qinling Tunnel of the Xikang Railway;

The third time is the East Qinling Tunnel of the Xi'an-Nanjing Railway; the fourth time is the Qinling Zhongnanshan Tunnel of the Baomao Expressway (Xikang Expressway)

The fifth time is the Qinling Tunnel Group of the Xihan Expressway (Beijing-Kunming Expressway),

The sixth time is the West Qinling Tunnel of the Lanzhou-Chongqing Railway under construction,

The seventh time is The Xicheng High-speed Railway Qinling Mountain Tunnel Group under construction.