Study on Identification of Construction Method for Ultra-Large-Span Tunnel

Table 1

Parameter values of each level of factor A.

Level	Compressive strength (MPa)	Internal friction angle φ (°)	Cohesive force C (MPa)	Volumetric weight γ (kN·m^−3)	Elasticity modulus E (GPa)	Poisson’s ratio μ
1	2	27.5	1.6	22	1.0	0.3
2	10	37	2.5	22	1.0	0.3
3	20	46.4	4	22	1.0	0.3
4	40	56.6	6	22	1.0	0.3
5	65	63	7.8	22	1.0	0.3

Note. The influences of volumetric weight, elasticity modulus, and Poisson's ratio were not considered.