Swelling Pressure of Double-Expansive Material and Its Active Support Effect for Coal Seam Gas Drainage Borehole

<div>Distribution of vertical stress around borehole. (a) No active support, 1d. (b) No active support, 2d. (c) No active support, 5d. (d) Active support, S<sub>1</sub>-1d. (e) Active support, S<sub>1</sub>-2d. (f) Active support, S<sub>1</sub>-5d.</div>

Advances in Materials Science and Engineering

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Figure 10

Figure 10: Swelling Pressure of Double-Expansive Material and Its Active Support Effect for Coal Seam Gas Drainage Borehole 