The construction of the Urumqi-Yuli Expressway in northwest China's Xinjiang Uygur Autonomous Region will soon turn "deep chasm into thoroughfare" across the Tianshan Mountains. The mega project has applied science-intense construction plans and cutting-edge mechanical equipment, which tided over myriad geological and climatic intricacies and complexities in the process of engineering.
The Tianshan Mountains, though majestic and magnificent, have impeded communication between the northern and southern parts of Xinjiang. In order to break through this natural barrier, the country started the construction of Urumqi-Yuli Expressway in early 2020.
The expressway, spanning approximately 319.7 kilometers from the region's capital city of Urumqi to Yuli County in Bayingolin Mongolian Autonomous Region, is a key segment of the G0711 Urumqi-Ruoqiang Expressway. It traverses the Tianshan Mountains and serves as the most convenient and efficient route from Urumqi to southern Xinjiang. To the east, it connects with Qinghai and southwest China, and even the new western land-sea corridor, significantly enhancing the land link between Xinjiang and coastal regions.
The construction project is conducted in the hinterland of the Tianshan Mountains, where the climate is cold, the altitude is high and the geological conditions are complex, making the construction extremely challenging.
Deep in the mountains, one section of the expressway, which spans over 11 kilometers, features 14 bridges and five tunnels, with total length of bridges and tunnels accounting for over 90 percent of the section.
To ensure smooth progress, the construction team built several access roads along steep cliffs and raced against time to advance construction.
"The biggest challenge we faced in this section was the construction of temporary access roads. We built a total of nine access roads for material transportation. There is frequent snowfall from every October to March of the following year, [so] we have only about five months for construction, which is a very short window," said Guo Dengke, deputy manager of the project management department for Section 3 of the China Communications Construction Xinjiang Urumqi-Yuli Expressway civil works.
The No. 8 cableway bridge, which spans 254 meters across a canyon, is quite famous among Internet users, who were astonished by its "paper-like" thickness. The construction team built the bridge as an access road to facilitate the pass of mechanical equipment and transport of materials. Despite its fragile appearance, it has played a crucial role in improving the overall construction efficiency.
"After building the cableway bridge, we were able to start construction ahead of schedule. This allowed us to advance the excavation and bridge work at the end of the section, effectively shortening the construction period by about seven months," said Guo.
The Tianshan Shengli Tunnel is another highlight and one of the most challenging parts in the expressway's construction. It has been drilled through on Monday morning, marking a significant milestone in China's infrastructure development.
With its construction starting in 2020, the 22.13-kilometer tunnel, a landmark transportation project is currently the longest expressway tunnel under construction in the world.
The Tianshan Shengli Tunnel is located in a sparsely populated area of the Tianshan Mountains, with an average construction elevation of over 3,000 meters and crossing 16 fault zones.
Over the past four years, more than 3,000 construction workers have overcome various geological challenges and risks through significant breakthroughs in new technologies, processes, and equipment. This project has become another important milestone in global tunnel engineering.
"In order to expedite the completion of the tunnel, our construction team and designers came up with the 'three-bore method' for construction, which introduces pioneer bores and uses the TBM (Tunnel Boring Machine) for excavation. The TBM's excavation speed is three to five times faster than manual drilling and blasting. We advanced the machine first, and then divided the main tunnel into several sections through transverse bores to increase the working planes. Therefore, we were able to complete the construction in more than four years," said Lu Zejian, Party branch secretary of the Section 5 of the China Communications Construction Xinjiang Urumqi-Yuli Expressway civil works
Crossing the Tianshan Mountains via National Highway 216 usually takes about three hours. With the completion of the Tianshan Shengli Tunnel, travel time will be reduced to just 20 minutes.
Urumqi-Yuli Expressway to turn 'deep chasm into thoroughfare' across Tianshan Mountains
