By Ashley Karen
The first breakthrough in the Jinxiu Tunnel has been made. This tunnel is an essential part of the Chengdu-Zigong high-speed railway in Sichuan province in southwest China.
The Jinxiu tunnel boring machine is China’s largest EPB TBM manufactured by CRCHI. It has a 12.79m diameter, a 135m length, a 3,000 tons weight, and a 7500kW installed power.
The tunnel is located in Jinjiang District, Chengdu, and is 2.6km long. While it passes below Chengdu’s southeast central ring road, the ballasted tracks of the current Chengdu East Ring Right Line, and the Chengdu-Guiyang high-speed railway, with many high-rise buildings above ground and a network of pipelines underground, it is only 8-60 m deep.
To manage the difficult geology, CRCHI produced the TBM design. Through the optimization of the instrument design, only two cutters were changed during the total 1.93km advance in the composite strata.
