Evolution Law of Floor Fracture Zone above a Confined Aquifer Using Backfill Replacement Mining Technology

Figure 8

Shear stress distributions at various depths: (a) width of excavated coal pillar is 10 m, (b) width of excavated coal pillar is 20 m, (c) width of excavated coal pillar is 30 m, and (d) width of excavated coal pillar is 40 m.

(a)

(b)

(c)

(d)