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CHAPTER 4

CONCLUSIONS
The follow:mg conclusions can be drawn from the damage survey performed for Operation
Ivy,

1. The damage auntatned by the various buildings of Structure 3.1.1 due to shot Mike was
as follows: The test panel= of Buildings i and 7 sustained only slight additional damage due to
air hlast. The steel frames of Building 2 suffered moderate plastic daformation, and the steel
sheeting of the rear face wae distorted inward between girts. The steei C(rame and aiding of

Building 6 received io apparent additional damage. The concrete frames of Buildings 3 and §
suffered moderaiz clastic defurmation. The rear wail cf Building 5 was blown off by the sir
blast. The shear walls of Building 4 were undamaged. However, 'arge cracks were opened in
the rocf slabs adjacent to the shear walls and roof girders. The overpressure wa3 approximately 14 pa,
2. Structure 3.1.3 suffered no major structural damage, ‘fle biast Joors were removed

prior tu the test, The wood frame air lock, which was left in places, was destroyed by the air
blast. The painted surface of the vent pipe was charred on the side facing Grourd Zero. The

Kaye overpressure was approximately 18 pyi.
3. All reiaforced-concrete seniburied instrumentation shelters apogearad to Lave parlurmed
their function satiafaciorily without exhibiting any peimary structural failures,
4, Of the many cre- story reinforced-concrete eurface ind seribuvini ytructures chaerved,
none were badly danage2. The only ser:ous structural fadures onwervec were confined to wing
walls designed to retain portions of the {ili on the semiburiec structures exposed sicel beams
and pipes attached tc these structures were damaged and aes!trayed by overprossuren of Tltne
ns,
and greater,

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5. Small buildings covered with thie sheet mota: over 2) .coaa] wuud eheathing penerclly
withstood overpressures up to 5 ana 6 pst. However, one vicuctui's of this type wae observed
badly damaged by an overpressure of 4.5 pai.
6, Lightly constructed wood frame shacks apparently sneathed with covcugaiee metal and
located in regions with overprac. .res yreater than 4 ps: wer? completely desizeyed. No ctructures of this type were observeo 1. regions subjected tn less than 4 pg) overpressure.

%. Palm trees were destroyed by air-biast overpressures uf 4 to S psi. J grecter, but

none were destroyed by overpressures less than 4 psi.

From the resuiis of the dynamic analysis of Struct; 4 3.1.0 presentcd in Sec. 2.6, the fn
lowing conclusions car be drawn:
1. The frec-air overpressure existing in the vicimity of Structure 3.1.1 for shot Mike ot
Operation Ivy was between 12 ard 14 psi.
2. Pressures measured by the side-on Laifle gaze at Station 611-01 on Engebi were more

reliable than those measured by the Pitot-static tube page at the same stztion.
3. The vifect on structural response of rise times of the order uf magnitude investigated
ig small,

121-122

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