
55Defect-Induced Damage
Chapter 3
e crater radius r = R is dened by the condition u = u
c
, where u
c
is the critical velocity
below which material is not damaged (crashed), giving (see Equation 3.41) for the crater
radius R:
R
Ah
u
h
c
2
23
2
2
=
⎛
⎜
⎞
⎟
− .
(3.43)
One can see that for a xed explosion energy E, there is a maximal lodging depth h
d
at
which a crater is formed and a depth h
m
at which a crater has maximum size R
m
:
h
A
u
hhRhh
d
c
mdmmd
=≈
2
04
06;.
. (3.44)
As follows from Equation 3.44, the depth for maximum crater size h
m
varies only as 1/4
power of the absorbed energy times the eective absorber radius. Combining Equations
3.44 and 3.43 gives