Environmental Engineering Reference
In-Depth Information
So,
W
2
q
W
q
A ¼ A
1
þ
A
2
¼ Wl 1
ð
cos
a
Þ þ
l 1
ð
cos
a
Þ
¼ Wl 1
ð
cos
a
Þ
1
þ
ð
2
:
43
Þ
The pendulum weight W, the bullet weight q, and the distance of gravity center
to the rotary center
l are
fixed. The structure constant of
the swing is
.
W
q
c ¼ Wl 1
þ
A
¼
c 1
ð
a
Þ
ð
:
Þ
cos
2
44
Because the structure constant c is known, the work capability/ability is directly
calculated from the swing angle. In general, each country takes TNT as a standard.
The ratio of the work ability/capacity of an explosive to that of TNT is its TNT
equivalent. The TNT equivalent of one explosive equals A (an explosive)/A (TNT).
(3) The work capacity/ability evaluation of an explosive by blasting cone
method
Throwing blasting cone is an intuitive and convincing method to evaluate the work
capability/ability of explosives. The speci
c volume of blasted cone is related with
the properties and mass of explosives, the properties of being blasted materials, and
the relative positions of media. All above factors are in consideration in the work
capability evaluation of explosives using throwing blasting cone. The standard
explosive and being test explosive with same mass are conducted in the exact same
conditions. The work ability/capability of an explosive is roughly evaluated by
comparing the volume of blasted cone to that obtained by the standard explosive.
In Fig.
2.19
, the blasting cone is measured by the ratio of its radius r to depth
w. n ¼
r
w
, n is index of throwing blasting action. If n = 1, the cone is standard
throwing cone; if n > 1, the cone is power throwing cone.
Fig. 2.19 Throwing blasting
cone
