A Solution to the Inherent List on Nimitz Class Aircraft Carriers
A Solution to the Inherent List on Nimitz Class Aircraft Carriers
A Solution to the Inherent List on Nimitz Class Aircraft Carriers
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Stress Calculati<strong>on</strong>s:<br />
k = coefficient that depends <strong>on</strong> <str<strong>on</strong>g>the</str<strong>on</strong>g> plate edge c<strong>on</strong>diti<strong>on</strong>s,<br />
aspect ratio (AR) of <str<strong>on</strong>g>the</str<strong>on</strong>g> panel, and positi<strong>on</strong> of point being c<strong>on</strong>sidered<br />
a := k • P •<br />
p = pressure based <strong>on</strong> 1000 psf <strong>on</strong> sp<strong>on</strong>s<strong>on</strong> shell plating<br />
b = panel width<br />
a = panel length<br />
t = plate thickness<br />
''simply_supported •<br />
lc,i fi := -5 ^ values are most c<strong>on</strong>servative<br />
a := 2Qft b := Bin based <strong>on</strong> 13 in separati<strong>on</strong> between stiffeners<br />
Jlb_<br />
P = 6.944-<br />
. 2<br />
in<br />
t := .25in<br />
^max allowable= 40,000 Jb_<br />
. 2<br />
in<br />
I AW with <str<strong>on</strong>g>the</str<strong>on</strong>g> General Specs (Secti<strong>on</strong> 100)<br />
^simply_supported • Simply_supported<br />
,., lb<br />
^simply_supported<br />
14083<br />
in<br />
"■'7<br />
^clamped • "Clamped<br />
I ^<br />
Maximum Allowable Stress for HTS is 40,000 psi. By adding stiffeners at 13 in, <str<strong>on</strong>g>the</str<strong>on</strong>g> stress falls well below that of simply<br />
supported and that of clamped. Simply supported and clamped structural cases are idealizati<strong>on</strong>s of structural member support<br />
illustrating zero stiffness and infinite stiffness, nei<str<strong>on</strong>g>the</str<strong>on</strong>g>r of which exists in any real-world structural system. On board ship,<br />
structural systems can be c<strong>on</strong>veniently approximated by <strong>on</strong>e or <str<strong>on</strong>g>the</str<strong>on</strong>g> o<str<strong>on</strong>g>the</str<strong>on</strong>g>r case, but in fact have stiffness between <strong>on</strong>e or <str<strong>on</strong>g>the</str<strong>on</strong>g> o<str<strong>on</strong>g>the</str<strong>on</strong>g>r.<br />
Navy structural analysis is based off clamped ends, <str<strong>on</strong>g>the</str<strong>on</strong>g>refore <str<strong>on</strong>g>the</str<strong>on</strong>g> stress should be well below maximum allowable.<br />
^clamped<br />
^max_allowabl(<br />
95