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Self-elevating Units-DNV-RP-C104
. The Self Elevating Unit.......................................................................................................................... 6
1.1 Introduction................................................................................................................ ...............................6
1.2 Important concept differences...................................................................................................................6
1.3 Special features .........................................................................................................................................6
1.4 General design principles .................................................................................................. .......................7
1.5 Load and Resistance Factored Design (LRFD) .................................................................................. ......7
1.6 Working Stress Design (WSD) ............... ....................... ...................... ....................... .............. ................8
1.7 Abbreviations ............................................................................................................................................8
2. Environmental Conditions ................................................................................................................... 8
2.1 Introduction................................................................................................................ ...............................8
2.2 Waves........................................................................................................................................................9
2.3 Current ....................................................................................................................................................13
2.4 Wind........................................................................................................................ ................................15
2.5 Water depth ................................................................................................................. ............................15
2.6 Bottom conditions ........................................................................................................... ........................16
3. Design Loads................................................................................................................. ........................ 17
3.1 Introduction................................................................................................................ .............................17
3.2 Permanent (G) and variable functional loads (Q) ...................................................................................17
3.3 Deformation loads (D) ....................................................................................................... .....................17
3.4 Environmental loads (E) ..................................................................................................... ....................17
3.5 Sea pressures during Transit (P, G and E loads)............................................................................. ........19
3.6 Accidental loads (A) ...............................................................................................................................19
4. Global Response Analysis..................................................................................................... ............... 19
4.1 Introduction................................................................................................................ .............................19
4.2 Leg stiffness .............................................................................................................. .............................20
4.3 Leg-to-hull interaction ...........................................................................................................................21
4.4 Global analysis for the elevated condition.................................................................................. ............23
4.5 Global analysis for the transit condition .................................................................................................32
4.6 Global analysis for the installation and retrieval conditions............................................................... ....36
5. Local Structural Analyses and Considerations ................................................................................. 37
5.1 Spudcans and lower part of leg - Elevated condition ......................................................................... ....37
5.2 Leg structure ............................................................................................................... ............................39
5.3 Leg joints by FEM analyses....................................................................................................................43
5.4 Hull and jack house ........................................................................................................ ........................43
6. Structural Strength (ULS) .................................................................................................................. 45
6.1 Introduction................................................................................................................ .............................45
6.2 Local strength of legs...................................................................................................... ........................47
6.3 Tubular joints ............................................................................................................. ............................49
6.4 Hull (Deck) structure .............................................................................................................................51
6.5 Spudcans .................................................................................................................... .............................52
6.6 Capacity for jacking and fixation system s ..............................................................................................53
7. Fatigue Strength (FLS)........................................................................................................................ 53
7.1 Introduction................................................................................................................ .............................53
7.2 Stress concentration factors ................................................................................................ ....................54
7.3 Design fatigue factors (DFF) ............. .................................................................................. ..................54
7.4 S-N curves ................................................................................................................. .............................55
7.5 Allowable extreme stress range .............................................................................................. ................55
7.6 Different operating conditions ........... .................................................................................. ..................55
7.7 Stochastic fatigue analysis .................. ............................................................................... .....................55
7.8 Simplified fatigue evaluation ..................................................................................................................56
7.9 Weibull parameter (h) .............................................................................................................................58
8. Accidental Strength (ALS) .................................................................................................................. 60
8.1 General ...................................................................................................................................................60
8.2 Ship impact ................................................................................................................. ............................60
8.3 Damaged structure .................................................................................................................................64
9. Overturning Stability Analyses ............................................................................................... ........... 65
9.1 Introduction................................................................................................................ .............................65
9.2 Stabilizing moment .................................................................................................................................65
9.3 Overturning moment .......................................................................................................... .....................66
9.4 Design requirement .................................................................................................................................669.5 Foundation stability ........................................................................................................ ........................66
10. Air Gap ..................................................................................................................... ............................ 67
10.1 Introduction.............................................................................................................................................67
10.2 Requirement ................................................................................................................ ............................67
10.3 Caution .................................................................................................................... ................................67
11. References .................................................................................................................. ........................... 68
Appendix A. Simplified global leg model of lattice legs.............................................................................. 70
A.1 Equivalent stiffness for Lattice legs ...................................................................................... ................................ 70
A.2 Euler load of legs ................................................................................................................................................... 74
A.3 Leg-to-hull interaction ........................................................................................................................................... 74
A.4 Natural period for simplified Jack-up models ................................................................................ ....................... 77
A.5 Simplified damping at resonance........................................................................................................................... 77
A.6 Idealization of lattice legs for wave, current and wind loads ............................................................... ................. 78
A.7 Forces in chord and brace members from equivalent leg section............ .............. .............. ........... ....................... 79
A.8 Leg Joint eccentricity ................ .............. .............. .............. ........... ....................... ......... ....................................... 81
A.9 Simplified analysis of legs in Transit ............ .......................................................................... .............................. 81
A.10 Simplified Wave motion analysis .......................................................................................................................... 84翻译哪位可以一起合作?也可以练习下英语的翻译的能力。
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