Simultaneous Operations of Pregrouting and Shaft Drilling in Shaft Construction

Table 1

Designed parameters of shafts.

Parameter	Main shaft	Auxiliary shaft	Ventilating shaft	Waste shaft
Designed excavated diameter	7.3 m	9.4 m	8.5 m	7.7 m
Designed effective diameter	6.4 m	8.3 m	7.5 m	5.2 m
Depth of the bottom	993 m	1015 m	893 m	1068 m
Material of the shaft wall	Reinforced concrete for upper alluvium, plain concrete for the bedrock
Thickness of shaft wall in the bedrock	0.4 m
Designed mining level 1	−962 m
Designed mining level 2	−1150 m
Selected special sinking method	Freezing + pregrouting	Freezing + pregrouting	Freezing + pregrouting	Drilling + pregrouting