Zhejiang Songyang Pumped Storage Drainage Tunnel

CRCHI deployed its third-generation pumped storage TBM, described in the source as a double-shield open-type machine, on the gravity drainage tunnel for the Songyang Pumped Storage Power Station. The five-kilometre alignment threads multiple sharp 30-metre-radius horizontal curves through Class II and III surrounding rock with heterogeneous lithology and complex joint development. Across the drive the TBM set a peak daily advance of 43 metres, a record monthly advance of 683 metres and an average monthly rate of 582 metres, cited as records for pumped storage projects globally. An onboard intelligent monitoring system reads thrust, torque and other excavation parameters in real time to refine the cutting strategy as ground conditions vary.