Rib Spalling 3D Model for Soft Coal Seam Faces with Large Mining Height in Protective Seam Mining: Theoretical and Numerical Analyses

<div>Observation results of borehole monitoring during the mining of 11223 working face. (a) Vertical cracks penetrating the layer at a depth of 32 m; (b) Vertical cracks formed at a depth of 16 m.</div>

Geofluids

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Figure 6

Figure 6: Rib Spalling 3D Model for Soft Coal Seam Faces with Large Mining Height in Protective Seam Mining: Theoretical and Numerical Analyses 