Research on the Reasonable Coal Pillar Width and Surrounding Rock Supporting Optimization of Gob-Side Entry under Inclined Seam Condition

Figure 5

The second invariant of deviatoric stress cloud in the surrounding rock of the roadway under different width coal pillars. (a) 5 m coal pillar, (b) 8 m coal pillar, (c) 10 m coal pillar, (d) 12.5 m coal pillar, (e) 15 m coal pillar, and (f) 20 m coal pillar.

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