Research Article
Study on the Migration Law of Overlying Strata on the Working Surface of Large Mining Height in Y.C.W Coal Mine
Figure 8
Immediate roof collapse diagram when the working face is advanced at different distances: (a) 0 m, (b) 40 m, (c) 78 m, (d) 80 m.
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(b) |
(c) |
(d) |