Study on the Instability Mechanism and Control Measures of a Roadway in a Mine with Retained Coal Pillars and Close Coal Seams

Figure 4

Distribution of the plastic zone of the surrounding rock in different stages of mining and excavation. (a) The mining roadway is excavated. (b) The 11173 mining face is mined out. (c) The 11173 mining face is mined out. (d) The 1118₁3 haulage roadway is excavated.

(a)

(b)

(c)

(d)