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 := kP- -<br />
p = pressure based <strong>on</strong> limiting ballast add for shell plating calculati<strong>on</strong>s<br />
'^imply_supported •<br />
a := 114in b :- 15-in<br />
lb<br />
P ^ 16.81- t := .3125n<br />
. 2<br />
in<br />
lb<br />
"max allowable= 40,000-<br />
m<br />
b = panel width<br />
a = panel length<br />
t = plate thickness<br />
^simply_supported ■ 'Simply_supported<br />
Ic , j •= 5 k values are most c<strong>on</strong>servative<br />
*t;lamped •<br />
based <strong>on</strong> 15 in separati<strong>on</strong> between stiffeners<br />
I AW with <str<strong>on</strong>g>the</str<strong>on</strong>g> General Specs (Secti<strong>on</strong> 100)<br />
I ^<br />
>2<br />
Jb_<br />
simply_supported 29048-<br />
. 2<br />
in<br />
'clamped • Clamped<br />
I ^<br />
'clamped<br />
Jb_<br />
19365-<br />
. 2<br />
m<br />
Maximum Allowable Stress for HTS is 40,000 psi. By adding stiffeners at 15 in, this stress falls below that of simply supported<br />
and that of clamped. Simply supported and clamped structural cases are idealizati<strong>on</strong>s of structural member support illustrating<br />
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, structural systems<br />
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. Navy structural<br />
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 falls well below maximum allowable.<br />
clamped ^«a, "max_allowabl<<br />
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