Tunnel Collapse Mechanism and Its Control Strategy in Fault Fracture Zone

Table 1

Calculation parameters.

Lithology	Rock mass parameters						Structural plane parameters
	Density (kg/m^3)	K (GPa)	(GPa)	C^b (MPa)	φ^b	(MPa)	K^n (GPa)	k^s (GPa)	C^j (MPa)	φ^j	(MPa)
Carbonaceous slate	2488	0.47	0.28	1.8	22	0.45	32.12	12.11	3.69	29	3.87
Rock mass parameters in fault	2467	0.33	0.11	1.23	20	0.31	12.38	4.33	2.55	20	1.26