A Solution to the Inherent List on Nimitz Class Aircraft Carriers

More documents

Recommendations

Info

Stress Calculations: No Stiffening k = coefficient that depends on <strong>the</strong> plate edge conditions, aspect ratio (AR) of <strong>the</strong> panel, and position of point being considered CT := kP- - p = pressure based on 50 I<strong>to</strong>ns of ballast addition b = panel width a = panel length t = plate thickness '^imply_supported ■" ■'- a := 20ft Pnew = 12-388-!^ in '^lamped " " ^ values are most conservative b :- 48in based on no stiffener addition t := .5in "niax_allowable= 28,000— in *^simply_supported ' "Simply.supported '^new U I AW with <strong>the</strong> General Specs (Section 100) /i ,2 ^simply_supported ~ 85626— in ^clamped • '^clamped'^newi j «^clamped= 57084- Jb_ . 2 in Maximum Allowable Stress for OS is 28,000 psi. If no stiffeners are added, <strong>the</strong> calculated stress is much greater than maximum allowable stress. As a result, stiffeners must still be added <strong>to</strong> be less than <strong>the</strong> maximum allowable stress (even with less ballast added and based off design load using maximum head of water). ^clamped'^^^max_allowabl< 120
Stress Calculations: Stiffening k = coefficient that depends on <strong>the</strong> plate edge conditions, aspect ratio (AR) of <strong>the</strong> panel, and position of point being considered a := kP, new p = pressure based on 50 I<strong>to</strong>ns of ballast addition b = panel width a = panel length t = plate thickness k . , _^ j •= 7' k_i j •= .5 k values are most conservative Nimply_supported • ■'- "^jlamped a .- 20ft b :- 24ir based on adding a stiffener down <strong>the</strong> nviddle of <strong>the</strong> deck Pnew = 12.388^ t := .5in in lb a max_allowable II ui = 28 -^"'""^ 000— ^ lAW with <strong>the</strong> General Specs t- (Section v 100) ^ in ^simply_supported • 'Simply_supported '^newl ^ ^simply_supported = 21407— . 2 in ^clamped • Clamped newl ^ clamped 14271 lb m Maximum Allowable Stress for OS is 28,000 psi. By adding stiffeners at 24 in AND with <strong>the</strong> addition of less ballast, <strong>the</strong> stress falls below that of simply supported and that of clamped. Simply supported and clamped structural cases are idealizations of structural member support illustrating zero stiffness and infinite stiffness, nei<strong>the</strong>r of which exists in any real-world structural system. On board ship, structural systems can be conveniently approximated by one or <strong>the</strong> o<strong>the</strong>r case, but in fact have stiffness between one or <strong>the</strong> o<strong>the</strong>r. Navy structural analysis is based off clamped ends, <strong>the</strong>refore <strong>the</strong> stress should be well below maximum allowable. As mentioned previously, however, adding ballast <strong>to</strong> <strong>the</strong> 4th deck is not feasible due <strong>to</strong> <strong>the</strong> inability <strong>to</strong> stiffen <strong>the</strong> 4th deck. ^clamped ^max_allowabl( 121
Page 1 and 2:
A Solution <strong
Page 3 and 4:
A Solution <strong
Page 5 and 6:
Table of Contents Abstract 3 Acknow
Page 7 and 8:
1.0 Introduction 1.1 Motivation Air
Page 9 and 10:
class. Changes to
Page 11 and 12:
classified into fo
Page 13 and 14:
o Control the KG g
Page 15 and 16:
the intact stabili
Page 17 and 18:
for ships propulsion, respectively.
Page 19 and 20:
combined with the
Page 21 and 22:
1.3.7 Ballast Addition 1.3.7.1 Wate
Page 23 and 24:
2% entrained air (by volume) in <st
Page 25 and 26:
Tank name Tank volume Ballast type
Page 27 and 28:
was successfully performed and <str
Page 29 and 30:
of each tank's location was added,
Page 31 and 32:
2.3 Preliminary Decision-Making Cos
Page 33 and 34:
All further costin
Page 35 and 36:
2.4 Structural Analysis One tank on
Page 37 and 38:
this pressure. This resulted in a r
Page 39 and 40:
2.4.1 Structural Modifications 2.4.
Page 41 and 42:
Main Deck Shell FR 165 - FR 180 Tra
Page 43 and 44:
2.4.1.3 Modifications to</s
Page 45 and 46:
3.1 Final POSSE Results The minimum
Page 47 and 48:
Table 6: Final Cost, Weight Additio
Page 49 and 50:
Corrosion coupons are placed in all
Page 51 and 52:
5.0 Recommendations 1. As can be se
Page 53 and 54:
References [I] Design Data Sheet 07
Page 55 and 56:
O CO ■*. CM d CVI d CVI d CO d CO
Page 57 and 58:
1
Page 59 and 60:
■ • s*; eo 1 CM ■
Page 61 and 62:
■ E 1- < O Y < ^^ i SS! m c in in
Page 63 and 64:
ON OC) 00 00 o o o ^ < ^ < o 00 o I
Page 65 and 66:
«n < 1-H ON H ^ 0\ 1—1 i-( o ©
Page 67 and 68:
in -^J r-- OS H 00 ■* ri o F^^ ^
Page 69 and 70: =» * o o o o o o o § § < S , , s
Page 71 and 72: i V) H % * l-H
Page 73 and 74: % H o o o © s * < © © o i^ © H
Page 75 and 76: * * H o o o o o o o o o e o o O o o
Page 77 and 78: M t» c« * ft ft H ft 00 O 00 r- O
Page 79 and 80: 1^ r-( 1-H M n
Page 81 and 82: Vi ^■ ««■ -^ ^^ * * o o o o o
Page 83 and 84: 4t S C/l r/i 00 * s M * o * < ly) C
Page 85 and 86: ^5- Q © © © © © © o o © ©
Page 87 and 88: "~" ~ 00 s ^ SS o s ■g Q ■* ja
Page 89 and 90: structural Analysis for Compartment
Page 91 and 92: Resulting Pressure on Sponson Plati
Page 93 and 94: Calculations to De
Page 95 and 96: Stress Calculations: k = coefficien
Page 99 and 100: FR 165 - FR 180 Transverse Bulkhead
Page 101 and 102: Design of Plating for Surface Ships
Page 105 and 106: Main Deck Shell FR 165 - FR 180 Tra
Page 119: Calculations to De
Page 123 and 124: Resulting Pressure on Shell Plating
Page 127 and 128: Stress Calculations for 227 I<stron
Page 129 and 130: Resulting Pressure on Inner Longitu
Page 137 and 138: Stress Calculations k = coefficient
Page 139 and 140: Resulting Pressure on Transverse Bu
Page 149 and 150: __ — __ — """ " *c; 1— ai S s
Page 151 and 152: o ON H 00 ^ ^ o > o -o B u H r^ 00
Page 153 and 154: MATERIAL WORK SHEET PERMA BALLAST®
Page 155 and 156: *• en * 5fc M S 00 00 * yj c« 1/
Page 157 and 158: CO 5t CO 00 en St 0\ CO 5t o © St
Page 159: * CO * * vT 00 * in r4~ vT * cr C/l
show all

A Solution to the Inherent List on Nimitz Class Aircraft Carriers

Create successful ePaper yourself

Delete template?

Save as template?