Eighty-one Days Ahead of Schedule, the CRCHI Double Shield TBM Construction Bid-section of Qingdao Metro Project Was Completed


The double shield hard rock TBM, jointly built by CRCHI and China Railway 18th Bureau for Qingdao Metro Line 4, has completed construction and tunnel through of bid-section. This is the first completed TBM construction bid-section of Qingdao Metro Line 4, which marks a staged victory for the construction.

With the joint efforts of China Railway 18th Bureau and CRCHI, the TBM construction achieved the highest monthly footage of 464 meters and the highest daily footage of 37.5 meters, creating the highest monthly cumulative TBM tunneling record of Qingdao Metro. The planned joint task was completed 81 days ahead of schedule, and the average effective daily footage of TBM tunneling reached 13 meters.

TBM construction in the shallow buried depth and small curve turn of the city subway is not only a great test to the construction organization, but also a test to equipment performance. With the support of project owners and industry experts, CRCHI developed the guidance system to adapt to the small curve of turning of double shield TBM and other targeted designs for the smooth implementation of projects.