Numerical Simulation of Surface Subsidence and Backfill Material Movement Induced by Underground Mining

Table 2

Microscopic parameters of the PFC model.

Micro parameters	Ore body	Slate	Marble
Particle contact modulus, Ec (GPa)	19.03	12.36	11.37
Particle stiffness ratio, kn/ks	1.8	2.0	2.5
Particle friction coefficient, μ	0.5	0.5	0.5
Parallel-bond radius multiplier,	1.0	1.0	1.0
Parallel-bond modulus, (GPa)	19.03	12.36	11.37
Parallel-bond stiffness ratio,	1.8	2.0	2.5
Normal strength, (MPa)	13.89 ± 2.78	6.56 ± 1.31	3.49 ± 0.70
Shear strength, (MPa)	20.84 ± 4.17	9.84 ± 1.97	5.24 ± 1.05