Identifying Effective Rock-Breaking Ratio Based on Rock Chip Information for Rock-Breaking Efficiency Evaluation of TBM

Table 2

TBM design parameters for water conveyance tunnel construction projects.

Design parameters	Lanzhou water source construction tunnel project		Wananxi water diversion project
	TBM 1	TBM 2	TBM
Excavation diameter (mm)	5480	5480	3830
TBM type	Double shield		Open
Number of disc cutters	37	30	23
Center disc cutter/diameter (mm)	6/432	4/432	4/432
Inner cutter/diameter (mm)	21/483	17/483	11/432
Gauge cuter/diameter (mm)	19/483	9/483	8/432
Maximum cutterhead spacing (mm)	86	83	89
Cutterhead speed (r·min^-1)	0~10.3	0~8.7	0~15.8
Cutterhead power (kW)	1800	2100	1200
Maximum cutterhead thrust (kN)	22160	11900	8972
Rating torque (kN·m)	3458	4210	1386
Breakaway torque (kN·m)	5878	6940	2287
Maximum tunneling speed (mm·min^-1)	120	120	120