The Computerized Design Program for Tunnel Blasting - Mining and ...
The Computerized Design Program for Tunnel Blasting - Mining and ...
The Computerized Design Program for Tunnel Blasting - Mining and ...
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5<br />
M18<br />
M20<br />
C (kg/m 3 )<br />
1.0<br />
0.8<br />
0.6<br />
0.4<br />
0.2<br />
C = 5.73x10 -3 RMR + 0.057<br />
R = 0.804<br />
0.0<br />
0 20 40 60 80 100<br />
RMR<br />
Figure 2: Correlation between the Rock Constant(c) <strong>and</strong> the RMR values<br />
M16<br />
M15<br />
M17<br />
M14<br />
M19<br />
M9<br />
M5<br />
M19<br />
M12<br />
M3 M1<br />
M13<br />
M7<br />
M11<br />
M14<br />
M17<br />
M16<br />
5<br />
M20<br />
300<br />
M15 M18<br />
400<br />
900<br />
Unit: [mm]<br />
1000<br />
1800<br />
1600<br />
5<br />
7<br />
8<br />
M18<br />
M15<br />
M19<br />
M7 M11<br />
(a) Cut designed by Lange<strong>for</strong>s’ <strong>for</strong>mulae (b) Cut designed by modified <strong>for</strong>mulae<br />
Figure 3: Comparison of cut design (H=4.5 m, c=0.46 kg/m 3 )<br />
Firstly, in case of the burn-cut, the cut section designed by the Lange<strong>for</strong>s’ <strong>for</strong>mulae had problems that a<br />
size of the cut section was designed largely in the given rock constant, shown as Figure 3(a), <strong>and</strong> the<br />
rock mass conditions was not adequately reflected. To correct the problems, the <strong>for</strong>mulae <strong>for</strong> the cut<br />
design were modified, based upon the results of tunnel blastings. <strong>The</strong> modified <strong>for</strong>mulae are as follows:<br />
1 st quadrangle : B1<br />
0.<br />
35<br />
= 1.<br />
5φ<br />
c<br />
(2)<br />
Linear charge concentration<br />
d ⋅φ<br />
⋅ c<br />
: l = 240<br />
S<br />
(3)<br />
ANFO<br />
2 nd <strong>and</strong> 3 rd quadrangle : B n = 1. 02 A'n−1⋅φ<br />
(4)<br />
4 th quadrangle <strong>and</strong> over : A n=<br />
2⋅ an−1<br />
(5)<br />
Copyright © 2005 International Society of Explosives Engineers<br />
2005G Volume 1 - <strong>The</strong> <strong>Computerized</strong> <strong>Design</strong> <strong>Program</strong> <strong>for</strong> <strong>Tunnel</strong> <strong>Blasting</strong> 4 of 10<br />
M13<br />
5<br />
M17<br />
M4<br />
M17<br />
5<br />
M9<br />
M19<br />
M15<br />
M18<br />
5<br />
8