Similar Physical Modeling of Roof Stress and Subsidence in Room and Pillar Mining of a Gently Inclined Medium-Thick Phosphate Rock

Figure 11

Deformation and failure characteristics of the roof for the 8 m ore pillars: (a) first step; (b) second step; (c) third step; (d) fourth step.

(a)

(b)

(c)

(d)