China’s largest EPBM breaks through on Jinxiu Tunnel
23 December 2022The first breakthrough has been made on the Jinxiu Tunnel, a key part of the Chengdu-Zigong high-speed railway in Sichuan province in south-west China.
The TBM, also named Jinxiu, is China’s largest EPB TBM developed by CRCHI. It has a 12.79m diameter, is 135m long, weighs 3,000 tons and has 7500kW installed power.
Located in Jinjiang District, Chengdu, the Jinxiu Tunnel is 2.6km long. Although it passes under Chengdu’s southeast central ring road and the ballasted tracks of the existing Chengdu East Ring Right Line and Chengdu-Guiyang high-speed railway, with many high-rise buildings above ground and a network of pipelines underground, it is only 8m to 60m deep.
To cope with the challenging environment, CRCHI tailored the TBM design. Through the optimisation of the tool design, only two cutters were changed during the total 1.93km advance in the composite strata.
