Table 3 Parameter table for the upper bench blasting.

From: Study on the influence of peripheral eye on over-excavation during mountain tunnel blasting construction

Name of the blast hole

Detonator segment

Number of eyes

Blast hole depth/m

Charge/kg

Maximum initiating charge in a single stage/kg

Cut hole 1

1

6

1.8

7.8

7.6

Cut hole 2

3

6

1.8

7.8

7.6

Auxiliary hole 1

5

8

1.5

6.4

6.0

Auxiliary hole 2

7

10

1.5

8.0

7.5

Auxiliary hole 3

9

12

1.5

9.6

9.0

Peripheral hole

11

31

1.6

6.4

3.8

Back to article page