Research Article

Influence Law of Interbedded Strata and Their Collapse on the Mining of Extremely Thick Coal Seam under Goaf

Figure 4

The evolution diagram of collapsing characteristics of overburden rock in the 60 m interlayer. Advance of the working face: (a) 40 m, (b) 60 m, (c) 80 m, (d) 100 m, (e) 140 m, and (f) 180 m.
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