By Lynda Myer
Production lines at China Railway Engineering Equipment Company’s (CREG) factories in Shunde, Guangdong and Zhengzhou, Henan, commissioned two hard rock TBMs.
With 225m length and 6.53m excavation diameter, CREC 1386 is the first TBM for the Guangdong Water Resources Allocation Project in Beibu Gulf Rim and it is due to be used for construction of the 10.82km tunnel on the project’s C1 section.
In order to overcoming the project’s complex geology and technical challenges such as hard rock and tunnel length, CREG drew on lessons from the design and application of TBMs in the Pearl River Delta water project and alpine railway construction.
As an inter-basin water diversion project, the Guangdong Water Resources Allocation Project has the largest diversion flow, the longest water transmission line, the most complex construction conditions and the largest total investment in the province’s history. It will benefit 18 million people along the line, alleviate water shortages, and improve supply continuity.
Advancing the belt inclined shaft and auxiliary ramp system of Xi’anshan Mining and Dressing Joint Project, was up to the second TBM (CREC 1360) that was jointly developed by China Railway Tunnel Group and CREG.
While the location of iron mine project is 7km south-west of Anshan City in Liaoning Province, TBM is going to dig 10.5km to create the inclined shaft and auxiliary ramp, and the 4.8km tunnel chamber will be constructed by drill and blast.
The long slope excavation, ventilation installation, as well as soft rock zones, are the challenges for this project.
Being designed for uphill and downhill tunneling construction with large slopes, CREC 1360 is 181m long, weighs 1200 tons, and has a 7.03m diameter cutterhead and adapts to the slope range of -8.53° to +12.5°.
The TBM has a minimum horizontal turning radius of 100m and minimum vertical curve turning radius of 300m.
