Ground Response and Mining-Induced Stress in Longwall Panel of a Kilometer-Deep Coal Mine

Table 2

Rock mass properties.

Rock mass	E (GPa)		Cohesion (MPa)	Friction (°)	Tensile strength (MPa)	m	n	k
Coal	2.8	0.20	1.3	30	0.2	0.0035	0.40	270
Mudstone	14.7	0.25	2.4	32	0.6	0.0021	0.56	320
Siltstone	17.5	0.25	5.0	33	1.3	0.0015	0.65	400
Sandstone	21.2	0.16	10.0	38	2.0	0.0010	0.70	750