Recently, the stepping ceremony for "Shuchang No. 1", the first multi-support TBM in Southwest China and a tunnel engineering powerhouse jointly developed by CRCHI and Sichuan Road & Bridge Group of Shudao Group, was successfully held at the TJ5 section of the Xichang-Xiangcheng Expressway, marking that the Yanyuan Tunnel of the Xichang-Xiangcheng Expressway has officially entered the TBM construction stage.

It is understood that the open-type TBM "Shuchang No. 1" is being used in the construction of the Yanyuan Tunnel on the Xichang-Xiangcheng Expressway. The designed cross-sectional dimension of the parallel pilot tunnel is 8.5 meters in diameter, with a tunneling length of 10 kilometers, and the tunnel follows a herringbone gradient along the route.

By focusing on analyzing the geological characteristics of the Yanyuan Tunnel and combining the design, use, and construction experience of more than 100 TBMs, the CRCHI R&D team added innovative designs such as steel segment support, auxiliary thrust, and bottom-arch anchor drilling rigs to the existing mature open-type TBM, so as to adapt to unfavorable geological conditions such as fault fracture zones, large deformation of soft rock, mud and water inrush, and low gas, ensuring that the TBM can continuously, evenly, and rapidly excavate under suitable geological conditions. When encountering unfavorable geology, it can pass through safely and steadily, improving the ability of the open-type TBM to cope with complex geological tunnels.

The use of the open-type TBM "Shuchang No. 1" in the construction of the Yanyuan Tunnel of the Xichang-Xiangcheng Expressway this time is an important measure to promote the safe and efficient construction of the tunnel engineering of the Xichang-Xiangcheng Expressway. Going forward, CRCHI will cooperate sincerely with Sichuan Road & Bridge Group of Shudao Group and work together for the early breakthrough of the Yanyuan Tunnel.