Study on the Mechanical Behavior of Double Primary Support of Soft Rock Tunnel under High Ground Stresses and Large Deformation

Table 2

Parameters of double primary support.

Double primary support	Deformation allowance		Gunite concrete		Reinforcing mesh		Bolt
	Location	Gap (mm)	Location	Thickness (mm)	Location	Space (cm)	Location	Type	Length (m)	Space (m)
								Resin	4
Primary 1	Arch wall	25	Whole ring	245	Whole ring	2020	Arch	Automatic	10	1.01.2
							Side wall	Automatic	10	1.01.2
Primary 2	Arch wall	15	Whole ring	230	Arch wall	2020	—	—	—	—