Coal and Gas Outburst Affected by Law of Small Fault Instability during Working Face Advance

Table 1

Numerical analysis of physical and mechanical parameters of coal rock stratum.

Lithology	Density (kg/m^3)	Bulk modulus (GPa)	Shear modulus (GPa)	Friction angle (°)	Cohesion (MPa)	Tensile strength (MPa)
Mudstone	2200	18.33	8.46	35	1.48	1.83
Sandy mudstone	2100	26.67	8.89	38	1.57	2.36
Medium sandstone	2300	21.67	10.00	34	2.97	2.4
Mudstone	2200	18.33	8.46	35	1.48	1.83
Fine sandstone	2300	21.21	10.94	34	2.4	2.6
Sandy mudstone	2100	26.67	8.89	36	1.57	2.36
Coal	1400	12.50	5.77	28	1.34	1.6
Sandy mudstone	2100	26.67	8.89	38	1.8	2.36
Medium sandstone	2300	21.67	10.00	34	2.97	2.4
Siltstone	2400	18.67	11.20	32	3.8	4