Study on Floor Mechanical Failure Characteristics and Stress Evolution in Double Predriven Recovery Rooms

Figure 14

Distribution curves of vertical stress around the DPRR with different sizes of inter-DPRR pillar: (a) 15 m, (b) 20 m, (c) 25 m, and (d) 30 m as the longwall mining.

(a)

(b)

(c)

(d)