2011 rhb final revised 02-11-2011
.pdf
5-7. DEMOLITION KNOTS. Several knots are used in demolitions. Figure 5-5 and Figure 5-6 show a few simple knots that can join demolitions to detonation cord.
Figure 5-5. VARIOUS JOINING KNOTS USED IN DEMOLITIONS
Figure 5-6. BRITISH JUNCTION
5 - 7
5-8. MINIMUM SAFE DISTANCES. Rangers must remain especially aware of their situations when using demolitions. Table 5-2 shows minimum safe distances for employing up to 500 pounds. For charges over 500 pounds, see Figure 5-7.
Table 5-2. MINIMUM SAFE DISTANCE FOR PERSONNEL IN OPEN (BARE CHARGE)
|
EXPLOSIVE |
SAFE DISTANCE |
|
EXPLOSIVE |
SAFE DISTANCE |
||
|
WEIGHT (LB) |
FEET |
METERS |
|
WEIGHT (LB) |
FEET |
METERS |
|
27 OR LESS |
985 |
300 |
|
175 |
1,838 |
560 |
30 |
1,021 |
311 |
200 |
1,920 |
585 |
||
35 |
1,073 |
327 |
225 |
1,999 |
609 |
||
40 |
1,123 |
342 |
250 |
2,067 |
630 |
||
45 |
1,168 |
356 |
275 |
2,136 |
651 |
||
50 |
1,211 |
369 |
300 |
2,199 |
670 |
||
60 |
1,287 |
392 |
325 |
2,258 |
688 |
||
70 |
1,355 |
413 |
350 |
2,313 |
705 |
||
80 |
1,415 |
431 |
375 |
2,369 |
722 |
||
90 |
1,474 |
449 |
400 |
2,418 |
737 |
||
100 |
1,526 |
465 |
425 |
2,461 |
750 |
||
125 |
1,641 |
500 |
500 |
2,625 |
800 |
||
150 |
1,752 |
534 |
--- |
--- |
--- |
||
Figure 5-7. MINIMUM SAFE DISTANCE FOR CHARGES OVER 500 POUNDS
DANGER
CHARGES ON TARGETS
FOR CHARGES ON TARGETS, THE MINIMUM RADIUS OF DANGER
IS 1,000 METERS. MINIMUM SAFE DISTANCE WHEN IN A MISSILE-PROOF
SHELTER FROM THE POINT OF DETONATION IS 100 METERS.
5-9. BREACHING CHARGES. For Table 5-3, the left column represents the thickness of reinforced concrete wall. The remaining 7 columns show the number of packages of C4 required to breach the wall using the charge placements shown in the drawings above the columns.
a.Use Table 5-3, Table 5-4, and Table 5-5 for breaching charges.
b.Use the formula in Figure 5-8 to calculate the charges (Table 3-5 and Figure 3-15 for more information).
c.Multiply number of packages of C4 from Table 5-3 by conversion factor from Table 5-4 for materials other than
reinforced concrete.
Table 5-3. BREACHING CHARGES FOR REINFORCED CONCRETE
|
|
|
|
PLACEMENT METHODS |
|
|
|
Reinforced |
|
|
|
|
|
|
|
Concrete |
C = 1.0 |
C = 1.0 |
C = 1.0 |
C = 1.8 |
C = 2.0 |
C = 2.0 |
C = 3.6 |
Thickness |
|
|
|
|
|
|
|
(ft) |
|
|
|
Packages of M112 (C4) |
|
|
|
|
|
|
|
|
|
|
|
2.0 |
1 |
5 |
5 |
9 |
10 |
10 |
17 |
2.5 |
2 |
9 |
9 |
17 |
18 |
18 |
33 |
3.0 |
2 |
13 |
13 |
24 |
26 |
26 |
47 |
3.5 |
4 |
21 |
21 |
37 |
41 |
41 |
74 |
4.0 |
5 |
31 |
31 |
56 |
62 |
62 |
111 |
4.5 |
7 |
44 |
44 |
79 |
88 |
88 |
157 |
5.0 |
9 |
48 |
48 |
85 |
95 |
95 |
170 |
5.5 |
12 |
63 |
63 |
113 |
126 |
126 |
226 |
6.0 |
13 |
82 |
82 |
147 |
163 |
163 |
293 |
6.5 |
17 |
104 |
104 |
186 |
207 |
207 |
372 |
7.0 |
21 |
111 |
111 |
200 |
222 |
222 |
399 |
7.5 |
26 |
137 |
137 |
245 |
273 |
273 |
490 |
8.0 |
31 |
166 |
166 |
298 |
331 |
331 |
595 |
|
|
|
|
|
|
|
|
5 - 9
Table 5-4. CONVERSION FACTORS FOR MATERIALS OTHER THAN REINFORCED CONCRETE |
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|||||||
|
MATERIAL |
|
CONVERSION FACTOR |
|
|
|
||
|
• EARTH |
|
|
0.1 |
|
|
|
|
|
• ORDINARY MASONRY |
|
|
|
|
|
||
|
• HARD PAN |
|
|
|
|
|
|
|
|
• SHALE |
|
|
|
|
|
|
|
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• ORDINARY CONCRETE |
|
0.5 |
|
|
|
||
|
• ROCK |
|
|
|
|
|
|
|
|
• GOOD TIMBER |
|
|
|
|
|
||
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• EARTH CONSTRUCTION |
|
|
|
|
|
||
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• DENSE CONCRETE |
|
0.7 |
|
|
|
||
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• FIRST-CLASS MASONRY |
|
|
|
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|||
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Table 5-5. MATERIAL FACTOR (K) FOR BREACHING CHARGES |
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Material |
|
R |
|
|
|
K |
||
|
|
|
|
|
|
|
||
Earth |
|
All values |
|
|
|
0.07 |
||
|
|
|
|
|
|
|
||
Poor masonry, shale, hardpan, good |
|
Less than 1.5 m (5 ft) |
|
|
|
0.32 |
||
timber, and earthen construction |
|
1.5 m (5 ft) or more |
|
|
|
0.29 |
||
Good masonry, concrete block, and rock |
|
0.3 m (1 ft) or less |
|
|
|
0.88 |
||
|
|
|
Over 0.3 m (1 ft) to less than 0.9 m (3 ft) |
|
0.48 |
|||
|
|
|
0.9 m (3 ft) to less than 1.5 m (5 ft) |
|
0.40 |
|||
|
|
|
1.5 M (5 ft) to less than 2.1 m (7 ft) |
|
0.32 |
|||
|
|
|
2.1 m (7 ft) or more |
|
|
|
0.27 |
|
Dense concrete and first-class masonry |
|
0.3 m (1 ft) or less |
|
|
|
1.14 |
||
|
|
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Over 0.3 m (1 ft) to less than 0.9 m (3 ft) |
|
0.62 |
|||
|
|
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0.9 m (3 ft) to less than 1.5 m (5 ft) |
|
0.52 |
|||
|
|
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1.5 M (5 ft) to less than 2.1 m (7 ft) |
|
0.41 |
|||
|
|
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2.1 m (7 ft) or more |
|
|
|
0.35 |
|
Reinforced concrete (factor does not |
|
0.3 m (1 ft) or less |
|
|
|
1.76 |
||
consider cutting steel) |
|
Over 0.3 m (1 ft) to less than 0.9 m (3 ft) |
|
0.96 |
||||
|
|
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0.9 m (3 ft) to less than 1.5 m (5 ft) |
|
0.80 |
|||
|
|
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1.5 M (5 ft) to less than 2.1 m (7 ft) |
|
0.63 |
|||
|
|
|
2.1 m (7 ft) or more |
|
|
|
0.54 |
|
|
|
|
|
|
|
|
|
|
Figure 5-8. FORMULA FOR COMPUTING SIZE OF CHARGE TO BREACH
CONCRETE, MASONRY, AND ROCK
P = R3KC
Where–
P = TNT required (in pounds) R = Breaching radius (in feet)
K = Material factor, which reflects the strength, hardness, and mass
of the material to be demolished
C = Tamping factor, which depends on the location and tamping
of the charge
5-10. TIMBER CUTTING CHARGES. Table 5-6 shows timber-cutting charge sizes. Figure 5-9 through Figure 5-15 show the types of charges and the formulas to use with each.
Table 5-6. TIMBER-CUTTING CHARGE SIZE
Figure 5-9. ABATIS
5 - 11
Figure 5-10. FORMULA FOR FALLEN TREE OBSTACLES OR TEST SHOT
P = D²/50 = P = 0.02D²
Where–
P = TNT required per tree (in pounds)
D = Diameter or least dimension of dimensioned timber; in inches
Figure 5-11. TIMBER-CUTTING RING CHARGE
Figure 5-12. TIMBER-CUTTING CHARGE (EXTERNAL)
Figure 5-13. FORMULA FOR EXTERNAL TIMBER-CUTTING CHARGE
P = D²/40 or P = 0.025D²
Where–
P = TNT required per target (in pounds)
D = Diameter or least dimension of dimensioned timber; in inches
Figure 5-14. TIMBER-CUTTING CHARGE (INTERNAL)
5 - 13
Figure 5-15. FORMULA FOR INTERNAL TIMBER-CUTTING CHARGE
P = D²/250 or P = 0.004D²
Where–
P = TNT required per target (in pounds)
D = Diameter or least dimension of dimensioned timber; in inches
5 - 15