Surface Movement and Deformation Law Caused by Different Coal Pillar Stagger Distances in Strip Filling IoT-Enabled Sustainable Mining

Table 1

The mechanical and physical parameters of the coal rock in the UDEC model.

Lithology	Thickness (m)	Density (kg·m^−3)	Bulk modulus (GPa)	Shear modulus (GPa)	Cohesion (MPa)	Friction angle (°)	Tensile strength (MPa)
Loess	80	1800	0.67	0.3	0.20	20	0.12
Sandstone	183	2462	15.7	5.9	0.25	31	0.20
Fine sandstone	59	2662	35.2	7.4	0.38	34	0.21
Siltstone	138	2627	26.4	5.1	0.48	34	0.24
Fine sandstone	81	2662	35.2	7.4	0.38	37	0.21
Sandy mudstone	34	2500	9.14	2.1	0.57	35	0.45
5# coal	2.95	1400	0.90	0.8	0.28	25	0.10
Fine sandstone	49	2500	9.14	1.9	0.38	35	0.21
8# coal	3.94	1400	0.90	0.8	0.28	25	0.10
Sandy mudstone	34	2500	9.14	2.1	0.57	35	0.45
12-1# coal	2.95	1400	0.90	0.8	0.28	25	0.10
Mudstone	143	2700	45.1	7.8	0.60	30	0.24