Strong Ground Pressure Mechanism and Control at the Longwall Top Coal Caving with a Single Key Stratum in Goaf

Figure 7

Overlying stratum subsidence in similar simulations: (a) extraction of the 4-2# coal seam at 85 m; (b) extraction of the 4-2# coal seam at 100 m; (c) extraction of the 4-2# coal seam at 130 m; (d) extraction of the 4-2# coal seam at 160 m; (e) extraction of the 4-2# coal seam at 190 m; (f) completed extraction of the 4-2# coal seam.

(a)

(b)

(c)

(d)

(e)

(f)