[Project Introduction] Super Engineering - Queershan Tunnel

Chinese engineers constructed a 7-kilometer tunnel through the Queer mountain from November 30, 2010 to September 26, 2017.

The Queershan tunnel is at an elevation of 4,300m above sea level, where the O2 concentration is only 60% of that in the flat region. The mountain is covered with snow and ice throughout the year, so it is extremely difficult to construct the tunnel. With continuous efforts of the engineers, the Queershan tunnel was successfully completed, and many new methods were used. The comprehensive anti-freezing method - "adding a thermal insulation layer on the inside of the lining, and installing transparent shed for snow protection at the entrance of the tunnel", greatly improves the resistance to frost and disaster. A health monitoring system based on wearable devices and an oxygen production and supply system were equipped to solve the lack of oxygen for the tunnel workers. A new standard for ventilation calculation applicable to tunnels at an altitude of 5000 meters was drafted, and the structures of axial fans in the high-altitude tunnels was optimized. A self-protection system to remove the ice on roads using natural hot spring was developed. Overall, the concept of green building was adopted in the construction process.

After the tunnel is completed and opened to traffic, it takes less than 20 minutes to pass through the Queershan tunnel, which is nearly 20 kilometers shorter than the original route. The dangerous mountain road including three avalanche-prone stretches with a total length of 4.7 kilometers, six debris flow-prone stretches with a total of 2220 meters, and many stretches with serious safety hazards such as frozen soil, landslides, snow damage, and ice damage is avoided. The Queershan tunnel ensure the safety and smooth traffic flows through the National Highway 317.