Surface Subsidence Control during Deep Backfill Coal Mining: A Case Study

Table 4

Surface deformation characteristics affected by the filling ratio.

Filling ratio (m)	Surface subsidence (mm)	Horizontal movement (mm)		Horizontal deformation (mm/m)		Inclined deformation (mm/m)		Curvature (mm/m^2)
		South-north direction	East-west direction	South-north direction	East-west direction	South-north direction	East-west direction	South-north direction	East-west direction
0	1575	651	622	1.7/−2.7	1.6/−2.5	3.1	2.9	0.01	0.01
60%	724	300	286	0.8/−1.3	0.7/−1.2	1.4	1.4	0.01	0.01
70%	563	241	230	0.6/−1.0	0.6/−0.9	1.1	1.1	<0.01	<0.01
80%	431	182	174	0.5/−0.8	0.4/−0.7	0.9	1.1	<0.01	<0.01
90%	379	124	118	0.3/−0.5	0.3/−0.5	0.6	0.6	<0.02	<0.02