Influence of Support Parameter and Excavation Methods on Statistical Distribution Characteristics of Surrounding Rock Pressure in Shallow-Buried Metro Tunnel

Table 2

Physical and mechanical parameters of the rock mass.

Jointed rock mass	Modulus of elasticity E(GPa)	Poisson’s ratio υ	Weight γ (kN/m^3)	Cohesive c (MPa)	Internal friction ψ (°)	Normal stiffness Kn (GPa)	Shear stiffness Ks (GPa)	Tensile strength T(MPa)
Soft rock	0.8	0.42	18.50	0.7	15			1
Hard rock	1.3	0.38	22.00	1.1	30			1.3
Structural surface of soft rock				0.004	2	8	3	0.02
Structural surface of hard rock				0.025	6	9	5.5	0.17