Failure Characteristics and Confined Permeability of an Inclined Coal Seam Floor in Fluid-Solid Coupling

Table 2

Physical and mechanical parameters of the 1066 inclined coal seam workface floor strata after changing.

Number	Lithology	Thickness (m)	Density (kg·m^−3)	Bulk modulus (GPa)	Shear modulus (GPa)	Tensile strength (MPa)	Cohesion (MPa)	Internal friction angle (°)	Permeability coefficient (m·s^−1)	Porosity
6	10-coal	3.4	1400	1.43	1.09	0.03	1.00	25	1e − 12	0.15
7	Siltstone	6.0	2650	4.54	4.30	1.10	4.90	40	7e − 12	0.13
8	Fine sandstone	9.0	2650	3.38	3.32	1.00	3.10	38	5e − 12	0.13
9	Sand mudstone	6.5	2600	1.73	1.09	0.60	2.60	25	0.6e − 11	0.09
10	Medium sandstone	12.0	2650	2.78	2.63	0.75	3.50	41	0.8e − 11	0.12
11	Sand mudstone	9.0	2600	1.73	1.09	0.45	2.90	25	0.6e − 13	0.09
12	Medium sandstone	3.0	2650	2.78	2.63	0.75	3.50	41	0.8e − 11	0.12
13	Siltstone	5.5	2650	4.54	4.30	1.00	4.40	40	0.5e − 11	0.14
14	Medium sandstone	2.0	2650	2.78	2.63	0.75	3.50	41	0.8e − 11	0.12
15	Aquifer	90.0	2500	4.20	3.12	1.40	3.20	38	1e − 10	0.31