Table 1 Borehole parameters.

From: Research on the impact of borehole parameters on the instability and precursor characteristics of large diameter borehole in coal seam

No.

Diameter/mm

Spacing/mm

Row spacing/mm

A1

3

–

–

A2

5

–

–

A3

7

–

–

A4

10

–

–

B1

5

15

–

B2

5

20

–

B3

5

25

–

B4

5

30

–

C1

5

20

10

C2

5

20

20

C3

5

20

30

C4

5

20

40

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