Numerical Simulation and Field Measurement Analysis of Fracture Evolution and Seepage Response of Key Aquiclude Strata in Backfill Mining

Table 1

The model geometry, physical, and mechanical parameters of overlying strata.

Lithology	Elastic modulus, GPa	Poisson’s ratio	Cohesion, MPa	Internal friction angle, °	Density, kN·m^-3	Permeability coefficient, ×10^-7 m·s^-1	Porosity
Overlying strata	8.5	0.28	4.5	32.0	24.0	0.20	0.10
Aquifer	22.0	0.25	8.0	34.0	26.0	11.57	0.25
Mudstone	6.7	0.32	2.7	24.0	22.0	0.05	0.01
Siltstone	16.3	0.28	8. 8	35.9	24.0	0.12	0.12
Fine sandstone	20.1	0.26	14.2	36.7	26.0	0.14	0.15
Immediate roof	7.2	0.32	3.5	28.0	22.0	0.08	0.05
Coal seam	5.5	0.30	2.5	26.0	14.0	0.30	0.20
Floor	25.0	0.25	12.0	32.0	25.0	0.15	0.02