Shock Compression in Condensed Matter, Williams-
can be attributed to the multiple-layered medium.
burg, Virginia, 1720 June 1991. American Physical
The reflections of the shock waves off the multiple
Society.
interfaces tended to decrease the depths of the
craters, especially in the ice layer, and increase the
Johnson, J.B., J.A. Brown, E.S. Gaffney, G.L. Blais-
dell and D.J. Solie (1992) Shock response of snow:
radii of the craters in the snow layer.
Analysis of experimental method and constitutive
In all cases the underlying frozen sediments
model development. USA Cold Regions Research
were not disturbed when point-detonating projec-
and Engineering Laboratory, CRREL Report 92-
tiles were fired into Eagle River Flats with the
12.
ground frozen and covered with a 0.30- to 0.60-m
ice sheet and 0.15- to 0.20-m of snow. The craters
ground. Part I: Explosion tests in Keweenaw silt.
formed by point-detonating projectiles of both
USA Snow, Ice and Permafrost Research Establish-
mortars and 105-mm howitzers were confined to
ment, Technical Report 30.
the overlying snow and ice sheet. With the excep-
tions of one 105-mm and one 60-mm dud, all of
ground. Part II: Explosion tests in frozen glacial
the point-detonating projectiles performed satis-
till, Fort Churchill. USA Snow, Ice and Permafrost
factorily. Delay-fused projectiles operated very er-
Research Establishment, Technical Report 30.
ratically in areas with frozen ground and an ice
Livingston, C.W . (1960) Explosions in ice. USA
cover.
Snow, Ice and Permafrost Research Establishment,
The mean scaled apparent radius of craters we
Technical Report 75.
measured in January 1992 formed by 105-mm
Mellor, M. (1965) Explosions and snow. USA Cold
point-detonating projectiles in the ice sheet of
shallow ponds were very close to those predicted
Regions Research and Engineering Laboratory,
from previous data for static spherical explosive
Monograph III A3a.
charges set on the ice surface, 0.90 vs. 0.94 m/kg1/3.
Cold Regions Research and Engineering Labora-
However, the measured vs. scaled apparent radius
tory, CRREL Report 82-40.
of the outer crater in the shallow snow cover was
Mellor, M. (1986a) Revised guidelines for blast-
50% greater than predicted, again indicating the
ing floating ice. USA Cold Regions Research and
difficulty in predicting crater size in a shallow,
Engineering Laboratory, Special Report 86-10.
multi-layered medium such as a thin snow layer
Mellor, M. (1986b) Blasting and blast effects in cold
over ice (Fig. 14).
regions. Part II: Underwater explosions. USA Cold
In summary, based on the results of the test fir-
Regions Research and Engineering Laboratory,
ing and observations of subsequent firing, winter
Special Report 86-16.
firing into Eagle River Flats under conditions simi-
Mellor, M. and P.V. Sellmann (1970) Experimen-
lar to those during the tests will not disturb the
tal blasting in frozen ground. USA Cold Regions
underlying sediments containing white phospho-
Research and Engineering Laboratory, Special Re-
rus particles. For 105-mm howitzers, a minimum
port 153.
of 25 cm of ice over frozen sediment or a mini-
mum of 30 cm of floating ice over shallow water is
Racine, C.H., M.E. Walsh, C.M. Collins, D.J. Cal-
kins and W .D. Roebuck (1992) Waterfowl mor-
required. For 60- and 81-mm mortars, minimums
tality in Eagle River Flats, Alaska: The role of mu-
are much less, on the order of 10 cm of ice. Winter
nition residues. USA Cold Regions Research and
firing with point-detonating projectiles when a
Engineering Laboratory, CRREL Report 92-5.
sufficiently thick snow and ice cover is present
appears to be the best approach to training in Eagle
Racine, C.H., M.E. Walsh, C.M. Collins, S. Tay-
lor, W .D. Roebuck, L. Reitsma and B. Steele (1993)
River Flats to prevent disturbance and mixing of
White phosphorus contamination of salt marsh
the WP-contaminated sediments.
pond sediments at Eagle River Flats, Alaska. USA
Cold Regions Research and Engineering Labora-
tory, CRREL Report 93-17.
LITERATURE CITED
Taylor, S., C.H. Racine, C.M. Collins and E. Gor-
don (1994) Ice formation in an estuarian salt marsh,
Johnson, J.B., J.A. Brown, E.S. Gaffney, G.L. Blais-
Alaska. USA Cold Regions Research and Engineer-
dell and M. Sturm (1991) Shock wave studies of
ing Laboratory, Special Report 94-17.
snow. In Proceedings, Seventh Topical Conference on
14
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