Failure Mechanism and Control of Lower Retracement Channel in Close-Distance Double-Thick Coal Seams

Figure 10

Stress and failure of the coal pillar with different aspect ratios. (a) Coal pillar aspect ratio of 1. (b) Coal pillar aspect ratio of 2. (c) Coal pillar aspect ratio of 3. (d) Coal pillar aspect ratio of 4. (e) Coal pillar aspect ratio of 5. (f) Multivariate analysis.

(a)

(b)

(c)

(d)

(e)

(f)