 |
China Builds Longest "Bulb-shaped" Railway Tunnel
The "bulb-shaped" Huangtupo No.3 tunnel on the Neijiang-Kunming railway in southwest China, the longest tunnel of this kind in the country, was completed Thursday.
The 3,005-meter-long tunnel, located at the Zhaotong City, Yunnan Province, runs in a 270-degree radian in the direction the mountain goes. The parallel distance between the entrance and exit of the tunnel is 660 meters.
Engineers in charge of the project said that the tunnel is located in a place of complex geological structure, with karst land forms, rock holes and faultage crisscrossing.
They said they developed five engineering technologies such as the geological technology for soft wall rock and the one-time blast technology targeted at big section, to complete the project. Construction of the tunnel began in October 1998.
The 879-kilometer-long railway starts from Neijiang in Sichuan Province and ends at Kunming, capital of Yunnan Province, via Guizhou Province.
In This Section
|
