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INTRODUCTION
OBJECTIVES
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The primary objective was to evaluate the magnitude of dynimic
pressure ‘an a damage paraneter for one type of target. In addition,
an attempt was made to d.termine the damage effect of the long
positive phase duration uf the shock wave.
Further information was required to determine whether or not the
damage curves devised after Operation UPSHOT-KNOTHOLE (see Reference
1) are valid and also to extend the present knowledge cf the effects
of atomic weapons on ordnance equipment.
1.2
BACKCROUND
The exposure of equipment in Operation CASTLE was a consequence
of the anomalous results obtained in UPSHOT-KNOTHOLE, specifically,
Shot 10 (see Reference i).
Ga most of the equipment exposure tests
in the past, the damage effects have been influenced by the presence
of varying amounts cf dust:‘behind the shock and on some by the
presence of both, a precursor phock wave and dust behind the precursor
wave.
Prior to UPSHOT-KNOTHCLE, static overpressure was the parareter
associated with damage.
The assumntton was made that other blast-wave
us
The data
obtained in Srot 10 indicated that “ayfiamic pressures measured were
higher by factors of three to four times and possibly more than the
dynamic pressures computed from measured overpressures using the
Rankine-ilugoniot relation (See Referente 2)... _Furthermcre, the damage
to ordnance equipment on Shots 9 and 10, UPSHOT--KNOTHOLE did not
correlate with measured overpressures.
Damage within the precursor
zone (Shot 10) was excessive as compared to idamage on Shot 9 at
corresponding overpressure levels. Studiesof damage sustained
indicated that dynamic pressure is the significant parameter to be
associated with damage.
The magnitudes of dynaniic pressure for
specific type damage are uncerta’
The observed values of dyna
subsequent investigations sugge:
.
Ld
=: pressure (see Ref. rence 2) and
:d that the damage sustained ea Shot
pressure-distarze curve (see Reference 3) using the normal -RankineHugoniot relation. These assumed values of dynamic pressure were used
in the ensuing statistical analysis. The test in Operation CASTLE
was to prove or disprove the validity of the assumpticn madeand to