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

Table 2

Parameter values of each level of factor C.

Level	Number of joint planes	Space of joint plane	Joint inclination angle (°)	Coefficient of surrounding rock integrity
1	4	0.2	0/90/45/135	0.1
2	3	0.3	0/90/45	0.2
3	2	0.4	0/90	0.4
4	2	0.8	0/90	0.6
5	2	1.5	0/90	0.75