Theoretical Calculation and Experimental Analysis on Initial Shock Pressure of Borehole Wall under Axial Decoupled Charge
Table 3
Experimental results of upper and middle air-decked charging structure.
Charge structure
Measuring point
Distance from hole bottom (m)
Relative distance from hole bottom
Peak voltage (V)
Peak strain
Peak pressure (MPa)
Up-air-deck charge structure
1
0
0
2.895
14092
359.346
2
0.035
2.92
3.106
15118
385.505
3
0.070
5.83
2.836
14180
361.590
4
0.105
8.75
2.106
10530
268.515
5
0.175
14.58
1.042
5210
132.855
6
0.245
20.41
0.332
1660
42.330
7
0.315
26.25
0.195
975
24.863
8
0.385
32.08
0.162
810
20.655
Middle-air-deck charge structure
1
0
0
3.345
16725
426.488
2
0.035
2.92
3.504
17521
446.778
3
0.070
5.83
3.258
16290
415.395
4
0.105
8.75
2.421
12105
308.678
5
0.140
11.67
1.273
6365
162.308
6
0.175
14.58
1.188
5940
151.470
7
0.210
17.50
1.193
5965
152.108
8
0.245
20.42
2.285
11425
291.338
9
0.280
23.33
3.150
15748
401.573
10
0.315
26.25
3.512
17559
447.753
11
0.350
29.17
3.276
16377
417.608
Note. Instead of actual pressure values, the peak pressures obtained by Hooke’s law are a rough representation of the distribution features of initial borehole wall shock pressure in the axial direction. The relative distance from hole bottom is the quotient of the distance from hole bottom and the hole diameter.
