Page 12 - Marine Structural Design

Contents ir
5.5 References ................................................................................................................................. 97
CHAPTER 6 OFFSHORE STRUCTURAL ANALYSIS ............................................................... 99
6 .I Introduction ............................................................................................................................... 99
6.1 . 1 General ............................................................................................................................... 99
6.1.2 Design Codes ..................................................................................................................... 99
6.1.3 Government Requirements ............................................................................................... 100
6.1.4 CertificatiodClassification Authorities ............................................................................ 100
6.1.5 Codes and Standards ........................................................................................................ 101
6.1.6 Other Technical Documents ............................................................................................. 102
6.2 Project Planning ....................................................................................................................... 102
6.2.1 General ............................................................................................................................. 102
6.2.2 Design Basis ..................................................................................................................... 103
6.2.3 Design Brief ..................................................................................................................... 105
6.3 Use of Finite Element Analysis ............................................................................................... 105
6.3.1 Introduction ...................................................................................................................... 105
6.3.2 Stiffness Matrix for 2D Beam Elements .......................................................................... 107
6.3.3 Stifmess Matrix for 3D Beam Elements .......................................................................... 109
6.4 Design Loads and Load Application ....................................................................................... 112
6.5 Structural Modeling ................................................................................................................. 114
6.5.1 General ............................................................................................................................. 114
6.5.2 Jacket Structures ............................................................................................................... 114
6.5.3 Floating Production and Offloading Systems (FPSO) ..................................................... 116
6.5.4 TLP, Spar and Semi-submersible ..................................................................................... 123
6.6 References ............................................................................................................................... 125
CHAPTER 7 LIMIT-STATE DESIGN OF OFFSHORE STRUCTURES ................................ 127

7.1 Limit State Design ................................................................................................................... 127
7.2 Ultimate Limit State Design .................................................................................................... 128
7.2.1 Ductility and Brittle Fracture Avoidance ......................................................................... 128
7.2.2 Plated Structures ............................................................................................................... 129
7.2.3 Shell Structures ................................................................................................................ 130
7.3 Fatigue Limit State Design ...................................................................................................... 134
7.3.1 Introduction ...................................................................................................................... 134
7.3.2 Fatigue Analysis ............................................................................................................... 135
7.3.3 Fatigue Design ................................................................................................................. 137
7.4 References ............................................................................................................................... 138

Part 11: Ultimate Strength

CHAPTER 8 BUCKLINGKOLLAPSE OF COLUMNS AND BEAM-COLUMNS ................ 141
8.1 Buckling Behavior and Ultimate Strength of Columns ........................................................... 141
8.1.1 Buckling Behavior ........................................................................................................... 141
8.1.2 Peny-Robertson Formula ................................................................................................. 143
8.1.3 Johnson-Ostenfeld Formula ............................................................................................. 144
8.2 Buckling Behavior and Ultimate Strength of Beam-Columns ................................................ 145
8.2.1 Beam-Column with Eccentric Load ................................................................................. 145
8.2.2 Beam-Column with Initial Deflection and Eccentric Load .............................................. 146
8.2.3 Ultimate Strength of Beam-Columns ............................................................................... 147
8.2.4 Alternative Ultimate Strength Equation - Initial Yielding .............................................. 148
8.3 Plastic Design of Beam-Columns ............................................................................................ 148
8.3.1 Plastic Bending of Beam Cross-section ........................................................................... 148