Failure Characteristics and Stability Control of Bolt Support in Thick-Coal-Seam Roadway of Three Typical Coal Mines in China

Figure 14

The field observation results: (a) the monitoring results of surface displacement in the roadway; (b) the monitoring results of axial load of flexible bolts; (c) borehole camera images and corresponding analysis; (d) field photo of test area.

(a)

(b)

(c)

(d)