Recently, at the construction site of the Tianshui Quxi Water Conveyance Tunnel project, accompanied by the roar of the cutterhead rotating and breaking rock, the "Yangtze River" TBM, jointly developed by CRCHI and Sinohydro Bureau 3, burst through the rock, successfully helping the upstream section of the Tianshui Quxi Urban and Rural Water Supply Project's water conveyance tunnel achieve breakthrough, marking the successful completion of the "Yangtze River" TBM's construction task.

Equipment at the project breakthrough site

The water conveyance tunnel of the Tianshui Quxi Urban and Rural Water Supply Project has a total length of 21.46 kilometers and is being excavated using two ultra-robust rescue-capable double-shield TBMs developed by CRCHI. On the basis of optimized structural design and ensuring the space requirements of a small-diameter TBM, the "Yangtze River" TBM adopted entirely new designs for the first time, including adjustable muck intake of the cutterhead, hydraulic motor rescue for small-diameter TBMs, and front-mounted advance grouting holes, greatly improving the rescue capability of this type of double-shield TBM and providing strong guarantees for efficient and safe construction.

Equipment roll-off

The "Yangtze River" TBM set out from the intake of the water conveyance tunnel on August 22, 2022, and completed the tunnel breakthrough in 483 days. It repeatedly achieved outstanding results during excavation, setting excavation records for a 4-meter double-shield TBM (with mine car mucking) of 705.225 meters in the highest monthly advance and 31.21 meters in the highest daily advance, and achieved an excellent result of exceeding 600 meters of excavation advance for four consecutive months.