Gob-Side Entry Retaining Technology with Advanced Empty Hole Butterfly-Shaped Weakening in Three-Soft Coal Seam in China

Figure 8

Stress distribution at different hole spacings: (a) L = 0.5D; (b) L = 1D; (c) L = 2D; (d) L = 3D; (e) L = 4D; (f) L = 5D.

(a)

(b)

(c)

(d)

(e)

(f)