Effect of Initiation Location within Blasthole on Blast Vibration Field and Its Mechanism
Table 1
Computational PPVs observed along the axial direction of the cylindrical charge.
z (m)
Radial PPV (cm/s)
Vertical PPV (cm/s)
Vector PPV (cm/s)
A
B
O
AB
A
B
O
AB
A
B
O
AB
2
19.63
17.9
18.96
18.96
11.03
8.85
10.15
10.01
22.52
19.97
21.51
21.44
5
8.58
7.66
8.23
8.18
3.38
2.89
3.04
2.95
9.22
8.19
8.77
8.70
10
2.42
2.15
2.31
2.31
1.58
1.37
1.50
1.49
2.89
2.55
2.75
2.75
15
1.07
0.95
1.02
1.02
0.96
0.88
0.94
0.93
1.44
1.29
1.39
1.38
25
0.39
0.35
0.37
0.38
0.49
0.46
0.48
0.48
0.63
0.58
0.61
0.61
40
0.16
0.14
0.15
0.15
0.31
0.29
0.30
0.30
0.35
0.32
0.34
0.34
The letters A, B, O, and AB, respectively, denote bottom initiation, top initiation, midpoint initiation, and two-end initiation. The vector PPV denotes the synthesis of the radial and vertical PPVs.
