By rosebell
As the world’s longest expressway tunnel, tunneling has been completed on China’s Tianshan Shengli Tunnel.
The 22.13km tunnel through the Tianshan Mountains is part of a new north-south link in the Xinjiang Uygur Autonomous Region.
Stretching from the regional capital of Urumqi in northern Xinjiang to Yuli County in southern Xinjiang, it is a key project of the Urumqi-Yuli Expressway. The scheduled date for inaugurating expressway, which is due to provide an alternative to the existing weather-prone, winding mountain roads, is the current year and the new road is slated to decrease journey times from about seven hours to just over three hours.
Being commenced in April 2020,the tunnel construction has faced challenges such as extreme cold, high altitudes, high ground stress, strong seismic activity as well as strict environmental requirements.
The Tianshan Mountains are known as a geological museum, featuring numerous fault zones, 16 of which the tunnel passes through. Its No. 2 ventilation shaft is 706m deep.
With the aim of overcoming the challenges, the contractor, China Communications Construction Co, broke down the construction into smaller, more manageable segments, allowing for faster excavation and so the original construction time was shortened by more than 25%.
Additionally, in order to minimising the environmental impact on the Tianshan No. 1 Glacier and snow leopard habitats, on-site facilities were established to contain wastewater and fully use gravel.
