Prediction of Bench Blasting Vibration on Slope and Safety Threshold of Blasting Vibration Velocity to Undercrossing Tunnel

Table 2

Blast holes’ parameters in tunnel blasting.

Classification	Blast hole angle (°)	Hole depth (m)	Number	Single hole charge (kg)
Cut holes	74° oblique hole	3.2	12	2.5
Relief holes	Vertical hole	3	37	1.8
Perimeter holes	88° oblique hole	3	28	1.1
Bottom holes	Vertical hole	3	9	2

Note. The cross-sectional area is 29 m², the total number of blast holes is 86, the total charge is 145 kg, the maximum charge per delay is 18.9 kg, and the specific consumption of the explosives is 1.6 kg/m³.