Conventional Breaching (Chapter 11)

Question 1

23. What are Opposed Counter Force charges effective against?

Answer 1

Effective against rectangular masonry or concrete columns 4’ thick or less

Question 2

15. What is the rounding rule of breaching radius for External Charge?

Answer 2

Round breaching radius up to the nearest ½ foot

Question 3

If the amount of charge explosive is less than 5 pounds, how thick would your charge be?

Answer 3

1 inches

Question 4

8. For breaching hard surface pavement, use how many pound of explosives for pavement?

Answer 4

1 pound for every 2 inches of pavement and tamp charge twice the thickness of the pavement

Question 5

20. If N is 2.5 or greater, how many charge should be use?

Answer 5

Round OFF to nearest whole number

Question 6

12. If concrete block with uncertain material factor, how would you identified it as?

Answer 6

Always assume as RF concrete

Question 7

10. For External Charges, Breaching Radius is ____

Answer 7

Same thickness of target

Question 8

18. If N is less than 1.25, how many charge should be use?

Answer 8

One charge

Question 9

11. How would determine if target material cannot be identified?

Answer 9

Assume target consists of strongest material in each specified groups

Question 10

14. The size of tamping should be…

Answer 10

Equal to or greater than Breaching Radius

Question 11

1. What is purpose of conventional breaching?

Answer 11

Used to destroy bridge, abutements, and compound walls

Question 12

17. What is the formula to find the number of charges?

Answer 12

N = W / 2R

Number of charges = width / 2 x Radius

Question 13

16. What is the rounding rule of breaching radius for Internal Charge?

Answer 13

Round breaching radius up to the nearest ¼ foot

Question 14

13. If you required to destroy a mason building with uncertain material, what will be the K (constant material factor)?

Answer 14

Assume it as first class masonry

Question 15

25. How much build up require to prime counter force charge?

Answer 15

Blasting cap required ½” build up

Question 16

22. What is the consideration of counterforce charge?

Answer 16

Charges should be diametrically opposed (explosive divide to 2 equal parts)
Obstacle must have at least 3 free faces or be freestanding

Question 17

2. What is critical factors in conventional breaching?

Answer 17

Size and confinement are most critical factors

charges will not cut rebar reinforcement

Question 18

3. What is the formula for breaching charges?

Answer 18

P = R^3 KC
(Pound = route 3 to Kansas City)
(Pound = Breaching Radius^3 x Constant for material factor x Tamping factor

Question 19

6. If the amount of charge explosive is 40 pounds to less than 300 pounds, how thick would your charge be?

Answer 19

4 inches

Question 20

24. What is the formula for counter force charge?

Answer 20

Pounds = 1.5 x Breaching Radius

Question 21

5. If the amount of charge explosive is 5 pounds to less than 40 pounds, how thick would your charge be?

Answer 21

2 inches

Question 22

19. If N is 1.25 and less than 2.5, how many charge should be use?

Answer 22

Two charge

Question 23

9. For Internal Charges, Breaching Radius is ____ the thickness of the target?

Answer 23

½ the thickness of the target

Question 24

7. If the amount of charge explosive is greater than 300 pounds, how thick would your charge be?

Answer 24

8 inches

Question 25

21. A counterforce charge relies on what?

Answer 25

Shockwave collision