Failure Mechanism for Surrounding Rock of Deep Circular Roadway in Coal Mine Based on Mining-Induced Plastic Zone

Figure 6

Distribution of the plastic zone around the circular roadway under deflection of the principal stress field: (a) β = 0°; (b) β = 30°; (c) β = 50°; (d) β = 70°.

(a)

(b)

(c)

(d)