Influencing Factor Analysis on the Anomalously Low-Friction Effect in the Block Rock Mass

Table 4

Mechanical parameters of coal and mudstone.

	Coal	Mudstone
Cohesion (MPa)	0.8	1.2
Internal friction angle (°)	26	28
Tensile strength (MPa)	0.21	0.69
Elastic modulus (GPa)	1.27	1.85
Poisson’s ratio	0.284	0.245