Fracture Mechanism in Overlying Strata during Longwall Mining

Figure 13

The distribution of principal stress and plastic zone when the excavation length is 30 m. (a) The distribution of minor principal stress; (b) the distribution of major principal stress; (c) the distribution of minor principal stress of the upper surface of IKS; (d) the distribution of major principal stress of the upper surface of IKS; (e) the plastic zone distribution of the overlying strata.

(a)

(b)

(c)

(d)

(e)