New Guanjiao Tunnel

Coordinates: 37°8′40″N 99°4′59″E / 37.14444°N 99.08306°E / 37.14444; 99.08306
From Wikipedia, the free encyclopedia
New Guanjiao Tunnel
A portal of New Guanjiao Tunnel during construction in 2011
LineQinghai–Tibet Railway
LocationGuanjiao Mountain
Coordinates37°8′40″N 99°4′59″E / 37.14444°N 99.08306°E / 37.14444; 99.08306
Start37°10′58″N 99°10′38″E / 37.18278°N 99.17722°E / 37.18278; 99.17722
End37°0′33″N 98°52′50″E / 37.00917°N 98.88056°E / 37.00917; 98.88056
Work begun2007
Opened28 December 2014 (2014-12-28)
Length32,645 metres (107,103 ft)
No. of trackstwo single
Track gauge1,435 mm (4 ft 8+12 in)
Operating speed160 km/h
Highest elevation3,381 metres (11,093 ft)
Lowest elevation3,324 metres (10,906 ft)

New Guanjiao Tunnel [1](Chinese: 新关角隧道; pinyin: Xīn Guānjiǎo Suìdào) is a tunnel on the 2nd line of Qinghai–Tibet Railway in Guanjiao Mountain, Qinghai province. It is dual-bored, double-track rail tunnel. The total length of the tunnel is 32.645 km (20.285 mi), which makes it the longest railway tunnel in China.

China Railway First Survey and Design Institute is responsible for the design. The New Guanjiao Tunnel was designed for two parallel single-track tunnels with speeds of up to 160 kilometres per hour (99 mph). The total construction duration was projected to be 5 years. The tunnel was bored in difficult geological conditions and high altitude, exceeding 3,300 metres (10,800 ft) above sea level. The construction started in 2007 and was completed in April 2014.[2] The tunnel was opened on 28 December 2014.[3]

The tunnel's northeastern portal (37°11′00″N 99°10′40″E / 37.1834°N 99.1778°E / 37.1834; 99.1778) is in Tianjun County, the southwestern portal (37°00′34″N 98°52′50″E / 37.0094°N 98.8805°E / 37.0094; 98.8805) is in Ulan County.