Temporal and Spatial Effect of Surrounding Rock and Supporting Construction of a Large Soil Tunnel

Table 1

Initial support design parameters.

Name	Position	Parameter
		Diameter/mm	Length/m
Hot rolled seamless steel pipe	140° range of arch	42	4.0
Mortar bolt	Sidewall	22
Locking catheter	Arch foot	42
Connecting bar	Between adjacent arches	ɸ22
Concrete	Initial spraying	5 cm
	Second lining arch	50 cm
	Secondary lining low side wall	60 cm
	Double lining invert	27 cm thickness
Steel arch	Holocycle	Type I20