Vertical Load and Settlement at the Foot of Steel Rib with the Support of Feet-Lock Pipe in Soft Ground Tunnel

Table 6

Basic parameters for excavation and support of the tunnel.

Items	Value
Type of steel ribs	I25a
Contact area at the foot of the steel rib (cm^2)	26 × 18
Interval of steel ribs (m)	0.6
Length of the feet-lock pipe (m)	5
Quantity and diameter of the feet-lock pipe at each foot	2Φ50  mm × 4 mm
Angle of the feet-lock pipe (°)	20°
Young’s modulus of steel ribs (GPa)	206
Radius of steel ribs (m)	8.66
Span of steel ribs (m)	17.06
Height of steel ribs (m)	7.15
Young’s modulus of the feet-lock pipe (GPa)	206
Young’s modulus of cement grout (GPa)	23