A Fractal and Numerical Simulation Coupled Study of Fracture Network during Coal Mining Excavation

Table 1

Mechanical properties of rocks.

Rock	Property
	E/GPa	𝜇	Thickness/m	Note
Sand and soil	15	0.29	50	5 m of each layer
Siltstone	36	0.2	10	key stratum
Mudstone	16	0.22	12	2 m of each layer
Fine sandstone	19	0.17	5/7	Inferior key stratum and floor
Coal	8.8	0.23	3	Excavation objects
Coarse sandstone	16	0.20	13	Roof, 3.25 m of each layer