effect of rise time in the range of overpreasures which bracket the pressure experienced by
Building 2 during shot Mize of Operation Ivy.
The results of the various analyses for Building 2 are presented in Tables 2.4 and 2.5.
The curves of final deflection va peak incident free-air overpressure and the recorded
values of {inal deficction for Building 2 are shown in Figs. 2.57 to 2.59. The range of possible
overpressures existing at the site for shot Mike of Operation Ivy {s determined by a comparison of the computed and recorded final def, *ctions,
Table 2.5 —COMPUTED FINAL RELATIVE DEFLECTIONS, SHOT MIKE,
UPERATION IVY, BUILDING 2
Final relative deflection for 0-sec
Final reiative deflec:ion for 0.018- ser
First story Second story Third story
Bz
yo
wo Nt
First sory Second story Third story
v
nov
Ya— 2
time of rise, %
Overpresesure
(Pros. pas
6
10
12
3
4
is
Ww
Ww
0
o
0.010
0.938
9.090
0.181
0.441
1,085
0
o
0,038
0.104
0.205
0.243
0,446
9.438
tome ot rise, ft
0
0.130
OTS
0.194
0.202
0.239
0,236
0,306
0
0.012
0.040
103
0.185
0,457
a
0.046
O.114
0,184
0,260
0.433
0.124
6.160
0.169
0.183
0.201
0.205
Table 2.6-—St4l.. .JM AND PINAL DEFLECTIONS FOR AUVILDING 3
Po
ve
Maximum
Rebound
Computed fina!
Measured final
13
“4
0.321
0.430
@.163
0.156
0.070
0.163
0.267
0.070
Po
13
Yn 7 YF
Maumum
4
Pre
Yam Yi
Maximum
0.403 0.411
Rebound
0.218 0.258
Computed fined 0,185 0.195
Measured final 0,150 0,196
3
Rebound
Computed final
Messred final
4
O27S 0.148
0.216
0
0,140
0.210
s
0.140
The analyses of Building 3 were used merely as a check of the results obtained from
Stracttse. The difficult nacre of the analyses made a greater number of investigations impractical. The resistance v+inee were obtained using column heights based on the resuta cf
the correlation of the Greenhouse analyses of Building 2. The results of the two analvnes oi
Building 3 are presented in Table 2.6.
A study of the computes usyimum relative defierfions (Table 2.4), the final deflecrtor va
overpressure curves (Figs. 2.57 to 2.59), and the final relative deflections (Table 2.5) det-rmined for Building 2 lead to the conciusiva tna .ne maximum alr -blast overpreseure in the
vicinity of Structure 3.1.1 was between 12 and 14 psi. Very little difference 1s obtaince in ine
structural response computed with a zero time of rise and with a rise time of 18 msec. In
view of the uncertainty regarding factors suc. as the effective mass of the superimpcsed dead
load and other approximations used in the Joad computations, it ia estimated that a time of rise
of the magnitude used in this analysia may be neglected without greatly affecting th: atructural
response. It may therefore be concluded that one cannot determine as a result of che analysis
of thia structure whether a significant time of rise was present in the air blast or not.
The comparison of the maximum and final computed deflectfons va the measw: ed final de~
Nections for Buliding 3 (Table 2.6) indicateg that a maxtmuum alr-blast overpressure of i2 or
13 psi would have caused the observed structural deformation. The analyses cf Building 3 involve a higher degree of uncertainty than those for Building 2 because of the structural rebcund
assumption and the strength properties of reinforced concrete columns,
f
¥
.
22
lati A caieiidatioc
ade
as, Oiasia 1
Building 2. Only two overpresaures with instantaneous rise time were investigated for this
f
ond
SECRET — RESTRICTED DATA
—
.
.
mm
aot
~
tees
LEA PALIT
aceteens
y
MEMSLINES SF
ZT
ee.
ap Aha oe
. 7.
nao
2h at
eine an
Ati.