Study on the Retention of Large Mining Height and Small Coal Pillar under Thick and Hard Roof of Bayangaole Coal

<div>Stress distribution in coal pillar with different widths. (a) Vertical stress in pillar. (b) Horizontal stress in pillar (axial direction of parallel roadway). (c) Horizontal stress in pillar (vertical roadway axial direction).</div>

Advances in Civil Engineering

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Figure 13

Figure 13: Study on the Retention of Large Mining Height and Small Coal Pillar under Thick and Hard Roof of Bayangaole Coal 