On August 3rd, the open-type TBM for Xichang to Shangri-La Expressway built by CRCHI was completed in Changsha, Hunan Province. With a length of about 170 meters and an excavation diameter of 8.53 meters, the TBM is the first synchronized flat-guided multi-support open-type TBM in Southwest China.

 The TBM will be applied for Yanyuan Tunnel of Xichang-Shangri-La Expressway in Sichuan Province. Yanyuan Tunnel is one of the nine super projects of this Expressway and has the characteristics of changeable extreme adverse geology and high requirements of ecological environmental protection. The construction difficulty degree can be recognized as the "ceiling" of the tunnel construction.

In view of the geological characteristics of the project, CRCHI combined the experience of designing and application for more than one hundred hard rock TBMs with the construction experience of similar projects at home and abroad, on the basis of existing mature manufacturing experience of open-type TBM. To ensure that the TBM can continuously and quickly excavate in the suitable geology and safely pass through the bad geology steadily, CRCHI innovatively designed steel pipe sheet lining support, auxiliary thrust, and bottom-arch anchor drilling rigs for the TBM to adapt to the negative geology situation of fault fracture zones, soft rocks deformation, sudden slurry, water surges and low gas. The ability of the open-type TBM to deal with the complex geology of road tunnel excavation is greatly improved.

It is said that the Xichang to Shangri-La Expressway Project is not only a beneficial line to improve the transportation conditions in Southeast areas but also a golden line to promote the development of regional advantageous resources and economic & social development. CRCHI will continue to provide strong service guarantee for the safe & efficient excavation and intelligent construction of Xichang to Shangri-La Expressway Project.

http://en.crchi.com/art/2023/8/3/art_40592_4605515.html