Page 13 - Marine Structural Design

X Contents
8.3.2 Plastic Hinge Load ........................................................................................................... 150
8.3.3 Plastic Interaction Under Combined Axial Force and Bending ....................................... 150
8.4 Examples ................................................................................................................................. 151
8.4.1 Example 8.1: Elastic Buckling of Columns with Alternative Boundaty Conditions ....... 151
8.4.2 Example 8.2 Two Types of Ultimate Strength Buckling vs . Fracture ...........................
8.5 References ............................................................................................................................... 153
154
CHAPTER9 BUCKLING ANDLOCALBUCKLINGOFTUBULARMEMBERS ............... 155
9.1 Introduction ............................................................................................................................. 155
9.1.1 General ............................................................................................................................. 155
9.1.2 Safety Factors for Offshore Strength Assessment ............................................................ 156
9.2 Experiments ............................................................................................................................. 156
9.2.1 Test Specimens ................................................................................................................. 156
9.2.2 Material Tests ................................................................................................................... 158
9.2.3 Buckling Test Procedures ................................................................................................ 163
9.2.4 Test Results ...................................................................................................................... 163
9.3 Theory of Analysis .................................................................................................................. 169
9.3.1 Simplified Elasto-Plastic Large Deflection Analysis ....................................................... 169
9.3.2 Idealized Structural Unit Analysis ................................................................................... 180
9.4 Calculation Results .................................................................................................................. 186
9.4.1 Simplified Elasto-Plastic Large Deflection Analysis ....................................................... 186
9.4.2 Idealized Structural Unit Method Analysis ...................................................................... 190
9.5 Conclusions ............................................................................................................................. 194
9.6 Example ................................................................................................................................... 195
9.7 References ............................................................................................................................... 196
CHAPTER 10 ULTIMATE STRENGTH OF PLATES AND STIFFENED PLATES ............... 199
10.1 Introduction ............................................................................................................................. 199
10.1.1 General ............................................................................................................................. 199
10.1.2 Solution of Differential Equation ..................................................................................... 200
10.1.3 Boundary Conditions ....................................................................................................... 202
10.1.4 Fabrication Related Imperfections and In-Service Structural Degradation ..................... 202
10.1.5 Correction for Plasticity ................................................................................................... 204
10.2 Combined Loads ...................................................................................................................... 205
10.2.1 Buckling - Serviceability Limit State .............................................................................. 205
10.2.2 Ultimate Strength - Ultimate Limit State ........................................................................ 206
10.3 Buckling Strength of Plates ..................................................................................................... 207
10.4 Ultimate Strength of Un-Stiffened Plates ................................................................................ 208
10.4.1 Long Plates and Wide Plates ............................................................................................ 208
10.4.2 Plates Under Lateral Pressure .......................................................................................... 209
10.4.3 Shear Strength .................................................................................................................. 209
10.4.4 Combined Loads .............................................................................................................. 209
10.5 Ultimate Strength of Stiffened Panels ..................................................................................... 209
10.5.1 Beam-Column Buckling ................................................................................................... 209
10.5.2 Tripping of Stiffeners ....................................................................................................... 210
10.6 Gross Buckling of Stiffened Panels (Overall Grillage Buckling) ............................................ 210
10.7 References ............................................................................................................................... 210
CHAPTER 11 ULTIMATE STRENGTH OF CYLINDRICAL SHELLS ................................... 213
1 1.1 Introduction ............................................................................................................................. 213
11.1.1 General ............................................................................................................................. 213
11.1.2 Buckling Failure Modes ...................................................................................................
11.2 Elastic Buckling of Unstiffened Cylindrical Shells ................................................................. 214
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