Permeability Enhancement and Gas Drainage Effect in Deep High Gassy Coal Seams via Long-Distance Pressure Relief Mining: A Case Study

Table 3

Physical and mechanical parameters of coal seams and strata in the model.

Lithology	Elastic modulus (GPa)	Poisson’s ratio	Internal friction angle (°)	Tensile strength (MPa)	Cohesion (MPa)	Density (kg/m^3)
Sandy mudstone	11.15	0.22	35	1.6	2.25	2565
Mudstone	10.45	0.30	32	1.4	1.9	2389
Coal seam	2.43	0.31	30	0.5	1.3	1460
Fine sandstone	20.82	0.17	37	3.0	5.9	2684
Gritstone	15.15	0.13	36	1.2	3.2	2704
Sand/mudstone interbed	21.64	0.19	35	2.0	2.4	2576