Marine Structural Design 4
Copyright 5
Contents 6
Preface to First Edition 28
Preface to Second Edition 30
Part 1 Structural Design Principles 32
1 - Introduction 34
1.1 Structural Design Principles 34
1.1.1 Introduction 34
1.1.2 Limit-State Design 35
1.2 Strength and Fatigue Analysis 37
1.2.1 Ultimate Strength Criteria 37
1.2.2 Design for Accidental Loads 39
1.2.3 Design for Fatigue 40
1.3 Structural Reliability Applications 42
1.3.1 Structural Reliability Concepts 42
1.3.2 Reliability-Based Calibration of Design Factor 43
1.3.3 Requalification of Existing Structures 44
1.4 Risk Assessment 45
1.4.1 Application of Risk Assessment 45
1.4.2 Risk-Based Inspection 45
1.4.3 Human and Organization Factors 46
1.5 Layout of This Book 46
1.6 How to Use This Book 48
References 48
2 - Marine Composite Materials and Structure 50
2.1 Introduction 50
2.2 The Application of Composites in the Marine Industry 50
2.2.1 Ocean Environment 51
2.2.2 Application in the Shipbuilding Industry 53
Pleasure Boats Industry 53
Recreational Applications 54
Commercial Applications 54
Military Applications 54
2.2.3 Marine Aviation Vehicles and Off-Shore Structure 54
2.3 Composite Material Structure 56
2.3.1 Fiber Reinforcements 57
Glass Fibers 58
Aramid Fibers 58
Carbon Fibers 59
2.3.2 Resin Systems 59
2.4 Material Property 60
2.4.1 Orthotropic Properties 62
2.4.2 Orthotropic Properties in Plane Stress 65
2.5 Key Challenges for the Future of Marine Composite Materials 66
References 67
3 - Green Ship Concepts 70
3.1 General 70
3.2 Emissions 70
3.2.1 Regulations on Air Pollution 71
3.2.2 Regulations on GHGs 71
3.2.3 Effect of Design Variables on the EEDI 71
3.2.4 Influence of Speed on the EEDI 74
3.2.5 Influence of Hull Steel Weight on the EEDI 74
3.3 Ballast Water Treatment 75
3.4 Underwater Coatings 78
References 78
4 - LNG Carrier 80
4.1 Introduction 80
4.2 Development 81
4.3 Typical Cargo Cycle 82
4.3.1 Inert 83
4.3.2 Gas Up 83
4.3.3 Cool Down 83
4.3.4 Bulk Loading 83
4.3.5 Voyage 83
4.3.6 Discharge 84
4.3.7 Gas Free 84
4.4 Containment Systems 84
4.4.1 Self-Supporting Type 85
Moss Tanks (Spherical IMO-Type B LNG Tanks) 85
IHI (Prismatic IMO-Type B LNG Tanks) 87
4.4.2 Membrane Type 87
GT96 88
TGZ Mark III 89
CS1 90
4.5 Structural Design of the LNG Carrier 90
4.5.1 ULS (Ultimate Limit State) Design of the LNG Carrier 90
Design of the LNG Carrier Hull Girder 90
Design Principles 90
Design Wave 91
Global Load Conditions 92
Load Condition 1—Maximum Hogging 92
Load Condition 2—Maximum Sagging 93
Combination of Stresses 93
Longitudinal Stresses 94
Transverse Stresses 94
Shear Stresses 95
Capacity Checks 95
General Principles 95
Hull Girder Moment Capacity Checks 96
Hull Girder Shear Capacity Check 97
4.6 Fatigue Design of an LNG Carrier 97
4.6.1 Preliminary Design Phase 97
4.6.2 Fatigue Design Phase 98
References 101
5 - Wave Loads for Ship Design and Classification 104
5.1 Introduction 104
5.2 Ocean Waves and Wave Statistics 104
5.2.1 Basic Elements of Probability and Random Processes 104
5.2.2 Statistical Representation of the Sea Surface 107
5.2.3 Ocean Wave Spectra 107
5.2.4 Moments of Spectral Density Function 110
5.2.5 Statistical Determination of Wave Heights and Periods 111
5.3 Ship Response to a Random Sea 112
5.3.1 Introduction 112
5.3.2 Wave-Induced Forces 114
5.3.3 Structural Response 115
5.3.4 Slamming and Green Water on Deck 116
5.4 Ship Design for Classification 119
5.4.1 Design Value of Ship Response 119
5.4.2 Design Loads per Classification Rules 119
General 119
Load Components 120
Hull Girder Loads 120
External Pressure 121
Internal Tank Pressure 122
References 123
6 - Wind Loads for Offshore Structures 126
6.1 Introduction 126
6.2 Classification Rules for Design 126
6.2.1 Wind Data 126
6.2.2 Wind Conditions 127
General 127
Wind Profile 128
Turbulence 130
Wind Spectra 130
Hurricanes 131
6.2.3 Wind Loads 131
General 131
Wind Pressure 132
Wind Forces 133
Circular Cylinders 133
Rectangular Cross Sections 133
Finite Length Effects 135
Other Structures 135
Dynamic Wind Analysis 136
Model Wind Tunnel Tests 138
Computational Fluid Dynamics 138
6.3 Research of Wind Loads on Ships and Platforms 139
6.3.1 Wind Loads on Ships 139
6.3.2 Wind Loads on Platforms 144
References 147
7 - Loads and Dynamic Response for Offshore Structures 150
7.1 General 150
7.2 Environmental Conditions 150
7.2.1 Environmental Criteria 150
Wind 151
Waves 151
Current 152
7.2.2 Regular Waves 152
7.2.3 Irregular Waves 153
7.2.4 Wave Scatter Diagram 153
7.3 Environmental Loads and Floating Structure Dynamics 156
7.3.1 Environmental Loads 156
7.3.2 Sea Loads on Slender Structures 156
7.3.3 Sea Loads on Large-Volume Structures 157
7.3.4 Floating Structure Dynamics 158
7.4 Structural Response Analysis 159
7.4.1 Structural Analysis 159
7.4.2 Response Amplitude Operator 160
7.5 Extreme Values 164
7.5.1 General 164
7.5.2 Short-Term Extreme Approach 166
7.5.3 Long-Term Extreme Approach 170
7.5.4 Prediction of Most Probable Maximum Extreme for Non-Gaussian Process 172
Drag/Inertia Parameter Method 174
Weibull Fitting 175
Gumbel Fitting 175
Winterstein/Jensen method 177
7.6 Concluding Remarks 178
References 179
Appendix A: Elastic Vibrations of Beams 180
Vibration of a Spring/Mass System 180
Elastic Vibration of Beams 181
8 - Scantling of Ship's Hulls by Rules 184
8.1 General 184
8.2 Basic Concepts of Stability and Strength of Ships 185
8.2.1 Stability 185
8.2.2 Strength 186
8.2.3 Corrosion Allowance 189
8.3 Initial Scantling Criteria for Longitudinal Strength 189
8.3.1 Introduction 189
8.3.2 Hull Girder Strength 190
Longitudinal stress 191
Shear stress 192
8.4 Initial Scantling Criteria for Transverse Strength 192
8.4.1 Introduction 192
8.4.2 Transverse Strength 193
8.5 Initial Scantling Criteria for Local Strength 193
8.5.1 Local Bending of Beams 193
Stiffeners 194
Girders 195
8.5.2 Local Bending Strength of Plates 196
8.5.3 Structure Design of Bulkheads, Decks, and Bottom 197
8.5.4 Buckling of Platings 197
General 197
Elastic compressive buckling stress 197
Buckling evaluation 200
8.5.5 Buckling of Profiles 200
References 201
9 - Ship Hull Scantling Design by Analysis 202
9.1 General 202
9.2 Design Loads 202
9.3 Strength Analysis Using Finite Element Methods 204
9.3.1 Modeling 204
Global Analysis 204
Local Structural Models 204
Cargo Hold and Ballast Tank Model 204
Frame and Girder Model 205
Stress Concentration Area 205
Fatigue Model 207
9.3.2 Boundary Conditions 207
9.3.3 Types of Elements 208
9.3.4 Postprocessing 208
Yielding Check 209
Buckling Check 209
9.4 Fatigue Damage Evaluation 210
9.4.1 General 210
9.4.2 Fatigue Check 210
References 211
10 - Offshore Soil Geotechnics 212
10.1 Introduction 212
10.2 Subsea Soil Investigation 212
10.2.1 Offshore Soil Investigation Equipment Requirements 213
General 213
Seabed Corer Equipment 214
Piezocone Penetration Test 214
Drill Rig 215
Downhole Equipment 215
Laboratory Equipment 215
10.2.2 Subsea Survey Equipment Interfaces 217
Onboard Laboratory Test 217
Core Preparation 218
Onshore Laboratory Tests 218
Nearshore Geotechnical Investigations 218
10.3 Deepwater Foundation 219
10.3.1 Foundations for Mooring 219
10.3.2 Suction Caisson 219
10.3.3 Spudcan Footings 220
10.3.4 Pipe Piles 223
Axial Capacity 223
References 225
11 - Offshore Structural Analysis 228
11.1 Introduction 228
11.1.1 General 228
11.1.2 Design Codes 228
11.1.3 Government Requirements 229
11.1.4 Certification/Classification Authorities 229
11.1.5 Codes and Standards 230
11.1.6 Other Technical Documents 231
11.2 Project Planning 232
11.2.1 General 232
11.2.2 Design Basis 232
Unit Description and Main Dimensions 232
Rules, Regulations and Codes 233
Stability and Compartmentalization 233
Materials and Welding 233
Temporary Phases 233
Operational Design Criteria 234
In-service Inspection and Repair 234
Reassessment 234
11.2.3 Design Brief 234
Analysis Models 234
Analysis Procedures 235
Structural Evaluation 235
11.3 Use of Finite Element Analysis 235
11.3.1 Introduction 235
Basic Ideas behind FEM 235
Computation Based on FEM 236
Marine Applications of FEM 236
11.3.2 Stiffness Matrix for 2D Beam Elements 237
11.3.3 Stiffness Matrix for 3D Beam Elements 239
11.4 Design Loads and Load Application 243
Dead Loads 243
Variable Loads 243
Static Sea Pressure 243
Wave-Induced Loads 243
Wind Loads 244
11.5 Structural Modeling 245
11.5.1 General 245
11.5.2 Jacket Structures 245
Analysis Models 245
Modeling for Ultimate Strength Analysis 246
Modeling for Fatigue Analysis 247
Assessment of Existing Platforms 247
Fire, Blast, and Accidental Loading 247
11.5.3 Floating Production and Offloading Systems (FPSO) 248
Structural Design General 248
Analysis Models 249
Modeling for Ultimate Strength Analysis 250
Modeling for Compartmentalization and Stability 252
Modeling for Fatigue Analysis 253
11.5.4 TLP, Spar, and Semisubmersible 255
References 258
12 - Development of Arctic Offshore Technology 260
12.1 Historical Background 260
12.2 The Research Incentive 263
12.3 Industrial Development in Cold Regions 264
12.3.1 Arctic Ships 264
12.3.2 Offshore Structures 265
12.4 The Arctic Offshore Technology Program 268
12.4.1 Three Areas of Focus 268
12.4.2 Environmental and Climatic Change 268
12.4.3 Materials for the Arctic 269
12.5 Highlights 270
12.5.1 Mechanical Resistance to Slip Movement in Level Ice 270
12.5.2 Ice Forces on Fixed Structures 271
12.5.3 Concrete Durability in Arctic Offshore Structures 273
12.6 Conclusion 273
References 274
13 - Limit-State Design of Offshore Structures 276
13.1 Limit-State Design 276
13.2 ULS Design 277
13.2.1 Ductility and Brittle Fracture Avoidance 277
13.2.2 Plated Structures 278
13.2.3 Shell Structures 279
13.3 FLS Design 284
13.3.1 Introduction 284
13.3.2 Fatigue Analysis 286
13.3.3 Fatigue Design 288
References 289
14 - Ship Vibrations and Noise Control 290
14.1 Introduction 290
14.2 Basic Beam Theory of Ship Vibration 291
14.3 Beam Theory of Steady-State Ship Vibration 292
14.4 Damping of Hull Vibration 293
14.5 Vibration and Noise Control 294
14.5.1 Propeller Radiated Signatures 294
14.5.2 Vortex Shedding Mechanisms 296
14.5.3 After-Body Slamming 298
14.6 Vibration Analysis 298
14.6.1 Procedure Outline of Ship Vibration Analysis 299
14.6.2 Finite Element Modeling 300
Lightship Weight Distribution 300
Loading Condition 301
Added Mass 301
Buoyancy Springs 302
14.6.3 Free Vibration 302
14.6.4 Forced Vibration 302
Further Reading 304
Part 2 Ultimate Strength 306
15 - Buckling/Collapse of Columns and Beam-Columns 308
15.1 Buckling Behavior and Ultimate Strength of Columns 308
15.1.1 Buckling Behavior 308
15.1.2 Perry–Robertson Formula 310
15.1.3 Johnson–Ostenfeld Formula 311
15.2 Buckling Behavior and Ultimate Strength of Beam-Columns 312
15.2.1 Beam-Column with Eccentric Load 312
15.2.2 Beam-Column with Initial Deflection and an Eccentric Load 313
15.2.3 Ultimate Strength of Beam-Columns 314
15.2.4 Alternative Ultimate Strength Equation—Initial Yielding 315
15.3 Plastic Design of Beam-Columns 316
15.3.1 Plastic Bending of Beam Cross Section 316
Rectangular Cross Section 316
Tubular Cross Section (t< <
I-Profile (t< <
15.3.2 Plastic Hinge Load 317
15.3.3 Plastic Interaction under Combined Axial Force and Bending 318
Rectangular Section 318
Tubular Members 319
15.4 Examples 319
15.4.1 Example 15.1: Elastic Buckling of Columns with Alternative Boundary Conditions 319
15.4.2 Example 15.2: Two Types of Ultimate Strength: Buckling versus Fracture 321
References 322
16 - Buckling and Local Buckling of Tubular Members 324
16.1 Introduction 324
16.1.1 General 324
16.1.2 Safety Factors for Offshore Strength Assessment 325
16.2 Experiments 325
16.2.1 Test Specimens 325
16.2.2 Material Tests 326
16.2.3 Buckling Test Procedures 329
16.2.4 Test Results 333
Eccentric Axial Compression Tests Using Large-Scale Specimens 333
Eccentric Axial Compression Test Using Small-Scale Specimens 335
Pure Bending Test for Small-Scale Specimens 337
16.3 Theory of Analysis 338
16.3.1 Simplified Elastoplastic Large Deflection Analysis 338
Preanalysis of Local Buckling 338
Critical Condition for Local Buckling 343
Post-Local-Buckling Analysis 343
COS Model 344
DENT Model 347
Procedure of Numerical Analysis 349
16.3.2 Idealized Structural Unit Analysis 351
Pre-ultimate-strength Analysis 351
System Analysis 353
Evaluation of Strain at Plastic Node 353
Post-Local-Buckling Analysis 355
16.4 Calculation Results 357
16.4.1 Simplified Elastoplastic Large Deflection Analysis 357
H Series 359
C Series 359
D Series 359
S Series 361
A Series and B Series 361
16.4.2 Idealized Structural Unit Method Analysis 361
Members with Constraints against Rotation at Both Ends 361
H Series 364
16.5 Conclusions 366
16.6 Example 367
16.6.1 Example 16.1: Comparison of the Idealized Structural Unit Method and Plastic Node Methods 367
References 368
17 - Ultimate Strength of Plates and Stiffened Plates 370
17.1 Introduction 370
17.1.1 General 370
17.1.2 Solution of Differential Equation 371
17.1.3 Boundary Conditions 372
17.1.4 Fabrication-Related Imperfections and In-service Structural Degradation 374
17.1.5 Correction for Plasticity 376
17.2 Combined Loads 376
17.2.1 Buckling—SLS 377
17.2.2 Ultimate Strength—ULS 378
17.3 Buckling Strength of Plates 379
17.4 Ultimate Strength of Unstiffened Plates 380
17.4.1 Long Plates and Wide Plates 380
17.4.2 Plates Under Lateral Pressure 381
17.4.3 Shear Strength 381
17.4.4 Combined Loads 381
17.5 Ultimate Strength of Stiffened Panels 381
17.5.1 Beam-Column Buckling 381
17.5.2 Tripping of Stiffeners 382
17.6 Gross Buckling of Stiffened Panels (Overall Grillage Buckling) 382
References 382
18 - Ultimate Strength of Cylindrical Shells 384
18.1 Introduction 384
18.1.1 General 384
18.1.2 Buckling Failure Modes 384
18.2 Elastic Buckling of Unstiffened Cylindrical Shells 385
18.2.1 Equilibrium Equations for Cylindrical Shells 385
18.2.2 Axial Compression 387
18.2.3 Bending 389
18.2.4 External Lateral Pressure 389
18.3 Buckling of Ring-Stiffened Shells 390
18.3.1 Axial Compression 390
18.3.2 Hydrostatic Pressure 391
General 391
Local Inter-ring Shell Failure 392
General Instability 392
Ring Stiffener Failure 392
18.3.3 Combined Axial Compression and External Pressure 393
18.4 Buckling of Stringer- and Ring-Stiffened Shells 393
18.4.1 Axial Compression 393
General 393
Local Panel Buckling 393
Stringer-Stiffened Cylinder Buckling 394
Local Stiffener Tripping 394
General Instability 394
18.4.2 Radial Pressure 395
18.4.3 Axial Compression and Radial Pressure 395
References 396
19 - A Theory of Nonlinear Finite Element Analysis 398
19.1 General 398
19.2 Elastic Beam-Column with Large Displacements 399
19.3 The Plastic Node Method 401
19.3.1 History of the Plastic Node Method 401
19.3.2 Consistency Condition and Hardening Rates for Beam Cross Sections 401
19.3.3 Plastic Displacement and Strain at Nodes 405
19.3.4 Elastic–Plastic Stiffness Equation for Elements 407
19.4 Transformation Matrix 408
19.5 Appendix A: Stress-Based Plasticity Constitutive Equations 410
19.5.1 General 410
19.5.2 Relationship between Stress and Strain in the Elastic Region 412
19.5.3 Yield Criterion 413
19.5.4 Plastic Strain Increment 415
Isotropic Hardening Rule 415
Kinematic Hardening Rule 417
19.5.5 Stress Increment–Strain Increment Relation in the Plastic Region 419
19.6 Appendix B: Deformation Matrix 420
References 421
20 - Collapse Analysis of Ship Hulls 424
20.1 Introduction 424
20.2 Hull Structural Analysis Based on the PNM 426
20.2.1 Beam-Column Element 426
20.2.2 Attached Plating Element 428
20.2.3 Shear Panel Element 430
20.2.4 Nonlinear Spring Element 431
20.2.5 Tension-Tearing Rupture 432
20.2.6 Computational Procedures 432
Computer Program SANDY 433
Computational Procedure 433
20.3 Analytical Equations for Hull Girder Ultimate Strength 434
20.3.1 Ultimate Moment Capacity Based on Elastic Section Modulus 435
20.3.2 Ultimate Moment Capacity Based on Fully Plastic Moment 436
20.3.3 Proposed Ultimate Strength Equations 437
20.4 Modified Smith Method Accounting for Corrosion and Fatigue Defects 439
20.4.1 Tensile and Corner Elements 439
20.4.2 Compressive Stiffened Panels 440
20.4.3 Crack Propagation Prediction 441
20.4.4 Corrosion Rate Model 441
20.5 Comparisons of Hull Girder Strength Equations and Smith Method 444
20.6 Numerical Examples Using the Proposed PNM 446
20.6.1 Collapse of a Stiffened Plate 446
20.6.2 Collapse of an Upper Deck Structure 448
20.6.3 Collapse of Stiffened Box Girders 448
20.6.4 Ultimate Longitudinal Strength of Hull Girders 450
20.6.5 Quasi-static Analysis of a Side Collision 453
20.7 Conclusions 454
References 455
21 - Offshore Structures Under Impact Loads 458
21.1 General 458
21.2 Finite Element Formulation 459
21.2.1 Equations of Motion 459
21.2.2 Load–Displacement Relationship of the Hit Member 460
21.2.3 Beam-Column Element for Modeling of the Struck Structure 461
21.2.4 Computational Procedure 461
21.3 Collision Mechanics 462
21.3.1 Fundamental Principles 462
21.3.2 Conservation of Momentum 463
21.3.3 Conservation of Energy 463
21.4 Examples 465
21.4.1 Mathematical Equations for Impact Forces and Energies in Ship/Platform Collisions 465
Problem 465
Solution 465
21.4.2 Basic Numerical Examples 466
Example 21.1: Fixed Beam under a Central Lateral Impact Load 466
Example 21.2: Rectangular Portal Frame Subjected to Impact Loads 467
Example 21.3: Tubular Space Frame under Impact Load 469
Example 21.4: Clamped Aluminum Alloy Beam Struck Transversely by a Mass 469
21.4.3 Application to Practical Collision Problems 472
Example 21.5: Unmanned platform struck by a supply ship 472
Example 21.6: Jacket platform struck by a supply ship 473
21.5 Conclusions 476
References 477
22 - Offshore Structures Under Earthquake Loads 478
22.1 General 478
22.2 Earthquake Design per API RP2A 479
22.3 Equations and Motion 480
22.3.1 Equation of Motion 480
22.3.2 Nonlinear Finite Element Model 481
22.3.3 Analysis Procedure 481
22.4 Numerical Examples 482
22.4.1 Example 22.1: Clamped Beam under Lateral Load 482
22.4.2 Example 22.2: Two-Dimensional Frame Subjected to Earthquake Loading 483
22.4.3 Example 22.3: Offshore Jacket Platform Subjected to Earthquake Loading 485
22.5 Conclusions 488
References 488
23 - Ship Collision and Grounding 490
23.1 Introduction 490
23.1.1 Collision and Grounding Design Standards 491
23.2 Mechanics of Ship Collision and Grounding 491
23.2.1 Internal Mechanics 491
23.2.2 External Mechanics 492
23.3 Ship Collision Research 492
23.3.1 Ship–Ship Collision Research 492
23.4 Ship Grounding Research 498
23.4.1 Ship Grounding on Shoal 499
Theoretical Model for Longitudinal Girders 499
Theoretical Model for Floors 500
Theoretical Model for Outer Bottom Plating 500
Theoretical Model for Stiffeners 500
23.5 Designs against Collision and Grounding 501
23.5.1 Buffer Bow 502
23.5.2 Sandwich Panels 502
23.5.3 Innovative Double-Hull Designs 502
References 503
Part 3 Fatigue and Fracture 506
24 - Mechanism of Fatigue and Fracture 508
24.1 Introduction 508
24.2 Fatigue Overview 508
24.3 Stress-Controlled Fatigue 510
24.4 Cumulative Damage for Variable Amplitude Loading 511
24.5 Strain-Controlled Fatigue 512
24.6 Fracture Mechanics in Fatigue Analysis 515
24.7 Examples 516
24.7.1 Example 24.1: Fatigue Life Cycle Calculation 516
24.7.2 Example 24.2: Fracture-Mechanics-Based Crack Growth Life Integration 517
References 518
25 - Fatigue Capacity 520
25.1 S–N Curves 520
25.1.1 General 520
25.1.2 Effect of Plate Thickness 522
25.1.3 Effect of Seawater and Corrosion Protection 523
25.1.4 Effect of Mean Stress 523
25.1.5 Comparisons of S–N Curves in Design Standards 524
25.1.6 Fatigue Strength Improvement 527
25.1.7 Experimental S–N Curves 527
25.2 Estimation of the Stress Range 528
25.2.1 Nominal Stress Approach 528
25.2.2 Hot-Spot Stress Approach 529
25.2.3 Notch Stress Approach 531
25.3 Stress Concentration Factors 532
25.3.1 Definition of SCFs 532
25.3.2 Determination of SCF by Experimental Measurement 532
25.3.3 Parametric Equations for SCFs 532
25.3.4 Hot-Spot Stress Calculation Based on FEA 533
25.4 Examples 535
25.4.1 Example 25.1: Fatigue Damage Calculation 535
References 537
26 - Fatigue Loading and Stresses 540
26.1 Introduction 540
26.2 Fatigue Loading for Oceangoing Ships 541
26.3 Fatigue Stresses 543
26.3.1 General 543
26.3.2 Long-Term Fatigue Stress Based on the Weibull Distribution 543
26.3.3 Long-Term Stress Distribution Based on the Deterministic Approach 544
26.3.4 Long-Term Stress Distribution—Spectral Approach 545
26.4 Fatigue Loading Defined Using Scatter Diagrams 547
26.4.1 General 547
26.4.2 Mooring- and Riser-Induced Damping in Fatigue Sea States 548
26.5 Fatigue Load Combinations 548
26.5.1 General 548
26.5.2 Fatigue Load Combinations for Ship Structures 549
26.5.3 Fatigue Load Combinations for Offshore Structures 550
26.6 Examples 551
26.6.1 Example 26.1: Long-Term Stress Range Distribution—Deterministic Approach 551
26.6.2 Example 26.2: Long-Term Stress Range Distribution—Spectral Approach 554
26.7 Concluding Remarks 555
References 556
27 - Simplified Fatigue Assessment 558
27.1 Introduction 558
27.2 Deterministic Fatigue Analysis 559
27.3 Simplified Fatigue Assessment 559
27.3.1 Calculation of Accumulated Damage 559
27.3.2 Weibull Stress Distribution Parameters 561
27.4 Simplified Fatigue Assessment for Bilinear S–N Curves 561
27.5 Allowable Stress Range 562
27.6 Design Criteria for Connections around Cutout Openings 562
27.6.1 General 562
27.6.2 Stress Criteria for Collar Plate Design 564
27.7 Examples 565
27.7.1 Example 27.1: Fatigue Design of a Semisubmersible 565
References 566
28 - Spectral Fatigue Analysis and Design 568
28.1 Introduction 568
28.1.1 General 568
28.1.2 Terminology 569
28.2 Spectral Fatigue Analysis 569
28.2.1 Fatigue Damage Acceptance Criteria 569
28.2.2 Fatigue Damage Calculated Using the Frequency–Domain Solution 570
Fatigue Damage for the ith Sea State 570
Fatigue Damage for All Sea States 571
28.3 Time–Domain Fatigue Analysis 572
28.3.1 Application 572
28.3.2 Analysis Methodology for Time–Domain Fatigue of Pipelines 572
28.3.3 Analysis Methodology for Time–Domain Fatigue of Risers 573
28.3.4 Analysis Methodology for Time–Domain Fatigue of Nonlinear Ship Response 574
28.4 Structural Analysis 574
28.4.1 Overall Structural Analysis 574
Space Frame Model 575
Fine FEA Model 576
Design Loading Conditions 576
Analysis and Validation 577
28.4.2 Local Structural Analysis 577
28.5 Fatigue Analysis and Design 577
28.5.1 Overall Design 577
28.5.2 Stress Range Analysis 578
28.5.3 Spectral Fatigue Parameters 578
Wave Environment 578
Stress Concentration Factors 579
S–N Curves 579
Joint Classification 579
Structural Details 581
28.5.4 Fatigue Damage Assessment 584
Initial Hot-Spot Screening 584
Specific Hot-Spot Analysis 584
Specific Hot-Spot Design 585
Detail Improvement 585
28.5.5 Fatigue Analysis and Design Checklist 585
28.5.6 Drawing Verification 586
28.6 Classification Society Interface 586
28.6.1 Submittal and Approval of Design Brief 586
28.6.2 Submittal and Approval of Task Report 586
28.6.3 Incorporation of Comments from Classification Society 586
References 586
29 - Application of Fracture Mechanics 588
29.1 Introduction 588
29.1.1 General 588
29.1.2 Fracture Mechanics Design Check 588
Maximum Allowable Stress 588
Minimum Required Fracture Toughness 588
Maximum Tolerable Defect Size 589
29.2 Level 1: The CTOD Design Curve 589
29.2.1 The Empirical Equations 589
29.2.2 The British Welding Institute CTOD Design Curve 590
29.3 Level 2: The Central Electricity Generating Board R6 Diagram 591
29.4 Level 3: The FAD 592
29.5 Fatigue Damage Estimation Based on Fracture Mechanics 593
29.5.1 Crack Growth Due to Constant Amplitude Loading 593
29.5.2 Crack Growth due to Variable Amplitude Loading 594
29.6 Comparison of Fracture Mechanics and S–N Curve Approaches for Fatigue Assessment 595
29.7 Fracture Mechanics Applied in Aerospace and Power Generation Industries 595
29.8 Examples 596
29.8.1 Example 29.1: Maximum Tolerable Defect Size in Butt Weld 596
References 597
30 - Material Selections and Damage Tolerance Criteria 600
30.1 Introduction 600
30.2 Material Selection and Fracture Prevention 600
30.2.1 Material Selection 600
30.2.2 Higher-Strength Steel 601
30.2.3 Prevention of Fracture 602
30.3 Weld Improvement and Repair 602
30.3.1 General 602
30.3.2 Fatigue-Resistant Details 603
30.3.3 Weld Improvement 603
Grinding 603
Controlled Erosion 604
Remelting Techniques 604
30.3.4 Modification of Residual Stress Distribution 604
Stress Relief 604
Compressive Overstressing 605
Peening 605
30.3.5 Discussion 605
30.4 Damage Tolerance Criteria 606
30.4.1 General 606
30.4.2 Residual Strength Assessment Using Failure Assessment Diagram 606
30.4.3 Residual Life Prediction Using Paris Law 607
30.4.4 Discussions 607
30.5 Nondestructive Inspection 608
References 609
Part 4 Structural Reliability 610
31 - Basics of Structural Reliability 612
31.1 Introduction 612
31.2 Uncertainty and Uncertainty Modeling 612
31.2.1 General 612
31.2.2 Natural versus Modeling Uncertainties 613
31.3 Basic Concepts 614
31.3.1 General 614
31.3.2 Limit State and Failure Mode 614
31.3.3 Calculation of Structural Reliability 614
Cornell Safety Index Method 615
The Hasofer–Lind Safety Index Method 616
Analytical Approach 618
Simulation Approach 618
31.3.4 Calculation by FORM 619
31.3.5 Calculation by SORM 620
31.4 Component Reliability 621
31.5 System Reliability Analysis 621
31.5.1 General 621
31.5.2 Series System Reliability 621
31.5.3 Parallel System Reliability 622
31.6 Combination of Statistical Loads 622
31.6.1 General 622
31.6.2 Turkstra's Rule 623
31.6.3 Ferry Borges–Castanheta Model 624
31.7 Time-Variant Reliability 625
31.8 Reliability Updating 626
31.9 Target Probability 627
31.9.1 General 627
31.9.2 Target Probability 627
31.9.3 Recommended Target Safety Indices for Ship Structures 628
31.10 Software for Reliability Calculations 628
31.11 Numerical Examples 629
31.11.1 Example 31.1: Safety Index Calculation of a Ship Hull 629
31.11.2 Example 31.2: ? Safety Index Method 630
31.11.3 Example 31.3: Reliability Calculation of Series System 631
31.11.4 Example 31.4: Reliability Calculation of Parallel System 632
References 633
32 - Structural Reliability Analysis Using Uncertainty Theory 634
32.1 Introduction 634
32.2 Preliminaries 635
32.2.1 Uncertainty Theory 635
32.2.2 Uncertain Reliability 637
32.3 Structural Reliability 638
32.4 Numerical Examples 640
32.5 Conclusions 644
References 644
33 - Random Variables and Uncertainty Analysis 646
33.1 Introduction 646
33.2 Random Variables 646
33.2.1 General 646
33.2.2 Statistical Descriptions 647
33.2.3 Probabilistic Distributions 648
Normal (or Gaussian) Distribution 648
Lognormal Distribution 648
Rayleigh Distribution 649
Weibull Distribution 649
33.3 Uncertainty Analysis 650
33.3.1 Uncertainty Classification 650
Inherent Uncertainty 650
Measurement Uncertainty 650
Statistical Uncertainty 650
Model Uncertainty 651
33.3.2 Uncertainty Modeling 651
33.4 Selection of Distribution Functions 651
33.5 Uncertainty in Ship Structural Design 652
33.5.1 General 652
33.5.2 Uncertainties in Loads Acting on Ships 653
Quasi-static Wave Bending Moment 653
Still-water Bending Moments 654
Load Combinations 654
33.5.3 Uncertainties in Ship Structural Capacity 654
References 655
34 - Reliability of Ship Structures 658
34.1 General 658
34.2 Closed Form Method for Hull Girder Reliability 659
34.3 Load Effects and Load Combination 661
34.4 Procedure for Reliability Analysis of Ship Structures 663
34.4.1 General 663
34.4.2 Response Surface Method 664
34.5 Time-Variant Reliability Assessment of FPSO Hull Girders 666
34.5.1 Load Combination Factors 666
34.5.2 Time-Variant Reliability Assessment 668
34.5.3 Conclusions 673
References 674
35 - Reliability-Based Design and Code Calibration 676
35.1 General 676
35.2 General Design Principles 676
35.2.1 Concept of Safety Factors 676
35.2.2 Allowable Stress Design 677
35.2.3 Load and Resistance Factored Design 677
35.2.4 Plastic Design 678
35.2.5 Limit-State Design 679
35.2.6 Life Cycle Cost Design 679
35.3 Reliability-Based Design 680
35.3.1 General 680
35.3.2 Application of Reliability Methods to the ASD Format 681
35.4 Reliability-Based Code Calibrations 682
35.4.1 General 682
35.4.2 Code Calibration Principles 682
35.4.3 Code Calibration Procedure 683
35.4.4 Simple Example of Code Calibration 684
Problem 684
Solution 684
35.5 Numerical Example for Tubular Structure 685
35.5.1 Case Description 685
35.5.2 Design Equations 686
35.5.3 Limit-State Function 687
35.5.4 Uncertainty Modeling 688
35.5.5 Target Safety Levels 689
35.5.6 Calibration of Safety Factors 690
35.6 Numerical Example for Hull Girder Collapse of FPSOs 691
35.7 LRFD Example for Plates of Semisubmersible Platforms 695
35.7.1 Case Description 695
35.7.2 Design Steps 696
35.7.3 Statistical Results 699
References 701
36 - Fatigue Reliability 702
36.1 Introduction 702
36.2 Uncertainty in Fatigue Stress Model 703
36.2.1 Stress Modeling 703
36.2.2 Stress Modeling Error 703
36.3 Fatigue Reliability Models 704
36.3.1 Introduction 704
36.3.2 Fatigue Reliability—S–N Approach 705
36.3.3 Fatigue Reliability—FM Approach 705
36.3.4 Simplified Fatigue Reliability Model—Lognormal Format 708
36.4 Calibration of FM Model by S–N Approach 709
36.5 Fatigue Reliability Application—Fatigue Safety Check 710
36.5.1 Target Safety Index for Fatigue 710
36.5.2 Partial Safety Factors 711
36.6 Numerical Examples 712
36.6.1 Example 36.1: Fatigue Reliability Based on Simple S–N Approach 712
Problem 712
Solution 712
36.6.2 Example 36.2: Fatigue Reliability of Large Aluminum Catamaran 713
Description of the Case 713
Results and assessment 715
References 718
37 - Probability- and Risk-Based Inspection Planning 720
37.1 Introduction 720
37.2 Concepts for Risk-Based Inspection Planning 720
37.3 Reliability-Updating Theory for Probability-Based Inspection Planning 722
37.3.1 General 722
37.3.2 Inspection Planning for Fatigue Damage 723
No Crack Detection 723
Crack Detected and Measured 724
Repair Events 724
Reliability Updating through Repair 724
37.4 Risk-Based Inspection Examples 725
37.5 Risk-Based “Optimum” Inspection 726
37.5.1 Inspection Performance 729
37.5.2 Inspection Strategies 730
What? 731
How? 731
When? 731
Who? 731
Why? 732
“Optimum” Inspection Method 732
Inspection Data System 734
References 735
Part 5 Risk Assessment 738
38 - Risk Assessment Methodology 740
38.1 Introduction 740
38.1.1 Health, Safety and Environment Protection 740
38.1.2 Overview of Risk Assessment 740
38.1.3 Planning of Risk Analysis 741
38.1.4 System Description 742
38.1.5 Hazard Identification 742
38.1.6 Analysis of Causes and Frequency of Initiating Events 743
38.1.7 Consequence and Escalation Analysis 743
38.1.8 Risk Estimation 744
38.1.9 Risk Reducing Measures 745
38.1.10 Emergency Preparedness 745
38.1.11 Time-Variant Risk 745
38.2 Risk Estimation 746
38.2.1 Risk to Personnel 746
Individual Risks 746
Society Risks and f-N Curves 747
38.2.2 Risk to Environment 747
38.2.3 Risk to Assets (Material Damage and Production Loss/Delay) 748
38.3 Risk Acceptance Criteria 748
38.3.1 General 748
38.3.2 Risk Matrices 749
38.3.3 The ALARP Principle 750
38.3.4 Comparison Criteria 751
38.4 Using Risk Assessment to Determine Performance Standard 752
38.4.1 General 752
38.4.2 Risk-Based Fatigue Criteria for Critical Weld Details 752
38.4.3 Risk-Based Compliance Process for Engineering Systems 753
References 753
39 - Risk-Based Decision-Making 756
39.1 Basic Probability Concepts 757
39.2 The RBDM Process 759
39.2.1 Risk Assessment 760
39.2.2 Risk Management 760
39.2.3 Impact Assessment 760
39.2.4 Risk Communication 761
39.3 A Step-by-step Example of the RBDM Process in the Field 761
References 765
40 - Risk Assessment Applied to Offshore Structures 766
40.1 Introduction 766
40.2 Collision Risk 767
40.2.1 Colliding Vessel Categories 767
40.2.2 Collision Frequency 767
Powered Ship Collision 768
Drifting Vessel Collisions 769
40.2.3 Collision Consequence 770
40.2.4 Collision Risk Reduction 770
40.3 Explosion Risk 771
40.3.1 Explosion Frequency 771
40.3.2 Explosion Load Assessment 773
40.3.3 Explosion Consequence 773
40.3.4 Explosion Risk Reduction 774
Prevent Gas Leakage 774
Prevent Ignitable Concentrations 775
Prevent Ignition 775
Prevent High Turbulence 775
Prevent High Blockage 775
Avoid Human Activities from Explosion Potential 776
Install Fire and Blast Barriers 776
Active Deluge on Gas Leakage 776
Improve Resistance of Equipment and Structures 776
40.4 Fire Risk 776
40.4.1 Fire Frequency 776
40.4.2 Fire Load and Consequence Assessment 777
Fire Types and Characteristics 777
Fire Response Analysis Procedures 778
Smoke Effect Analysis 778
Structural Response to Fire 779
40.4.3 Fire Risk Reduction 779
40.4.4 Guidance on Fire and Explosion Design 779
40.5 Dropped Objects 780
40.5.1 Frequency of Dropped Object Impact 780
Annual Lift Number and Load Distribution 781
Probability of Dropped Load 781
Probability of Hitting Objects 781
40.5.2 Drop Object Impact Load Assessment 782
Fall through the Air 782
Impact with Water 782
Fall through Water 783
40.5.3 Consequence of Dropped Object Impact 783
40.6 Case Study—Risk Assessment of Floating Production Systems 784
40.6.1 General 784
Process Systems 784
Marine Systems 785
Structural Systems 785
40.6.2 Hazard Identification 786
40.6.3 Risk Acceptance Criteria 787
40.6.4 Risk Estimation and Reducing Measures 788
Process Leakage 788
Offloading and Shuttle Tanker Risk 788
Marine System Risk 789
Collision Risk 790
Explosion Risk 790
Fire Risk 790
Dropped Object Risk 790
40.6.5 Comparative Risk Analysis 791
40.6.6 Risk-Based Inspection 791
Structures Including Vessel Hull and Topside Structures 791
Mooring Systems and the Thruster System that Assists the Station-Keeping System 792
Import/Export Systems Such as Risers, Flow Lines, and Offloading Systems 792
40.7 Environmental Impact Assessment 792
References 793
41 - Formal Safety Assessment Applied to Shipping Industry 796
41.1 Introduction 796
41.2 Overview of FSA 797
41.3 Functional Components of the FSA 799
41.3.1 System Definition 799
The Ship Hardware 799
The Stakeholders 800
The Ship Life Cycle 800
41.3.2 Hazard Identification 800
Collision and Grounding 801
Fire 802
Explosion 803
Loss of Structural Integrity 803
Loss of Power 804
Hazardous Material 804
Loading Errors 804
Extreme Environmental Conditions 805
41.3.3 Frequency Analysis of Ship Accidents 805
41.3.4 Consequence of Ship Accidents 806
Loss of Human Life 806
Loss of Cargo 806
Damage to Ship or Other Ships 807
Damage to the Environment 807
41.3.5 Risk Evaluation 807
41.3.6 Risk Control and Cost–Benefit Analysis 808
41.4 HOF in the FSA 808
41.5 An Example Application to the Ship's Fuel System 809
41.6 Concerns Regarding the Use of FSA in Shipping 810
References 811
42 - Economic Risk Assessment for Field Development 812
42.1 Introduction 812
42.1.1 Field Development Phases 812
42.1.2 Background of Economic Evaluation 813
42.1.3 Quantitative Economic Risk Assessment 814
42.2 Decision Criteria and Limit-State Functions 815
42.2.1 Decision and Decision Criteria 815
A. Should the Field be Developed Now? 815
B. Given That the Field is Under Development, How Should It Be Developed? 815
C. How Should the Project be Carried Out? 815
42.2.2 Limit-State Functions 815
42.3 Economic Risk Modeling 816
42.3.1 Cost Variable Modeling 816
Costs of Facilities and Drilling 817
Costs of Operation and Maintenance 817
42.3.2 Income Variable Modeling 817
Reservoir Size and Production Profile 817
Prices of Oil, Gas, and LNG 818
Taxes, Inflation, and Interest Rates 818
42.3.3 Failure Probability Calculation 818
42.4 Results Evaluation 819
42.4.1 Importance and Omission Factors 819
42.4.2 Sensitivity Factors 820
42.4.3 Contingency Factors 820
References 821
Appendix A: Net Present Value and Internal Rate of Return 821
Net Present Value 822
Internal Rate of Return 822
43 - Human Reliability Assessment 824
43.1 Introduction 824
43.2 Human Error Identification 825
43.2.1 Problem Definition 825
43.2.2 Task Analysis 826
43.2.3 Human Error Identification 826
43.2.4 Representation 827
43.3 Human Error Analysis 827
43.3.1 Human Error Quantification 827
43.3.2 Impact Assessment 828
43.4 Human Error Reduction 828
43.4.1 Error Reduction 828
43.4.2 Documentation and Quality Assurance 829
43.5 Ergonomics Applied to Design of Marine Systems 829
43.6 QA and Quality Control 830
43.7 Human and Organizational Factors in Offshore Structures 831
43.7.1 General 831
43.7.2 Reducing Human and Organizational Errors in Design 832
References 833
44 - Risk-Centered Maintenance 834
44.1 Introduction 834
44.1.1 General 834
44.1.2 Application 835
44.1.3 RCM History 835
44.2 Preliminary Risk Analysis 837
44.2.1 Purpose 837
42.2.2 PRA Procedure 837
44.3 RCM Process 839
44.3.1 Introduction 839
44.3.2 RCM Analysis Procedures 840
44.3.3 Risk-Centered Maintenance (Risk-CM) 847
Operational Risk Assessment 847
Human Contribution to Risk 848
44.3.4 RCM Process—Continuous Improvement of Maintenance Strategy 848
44.4 RCM Application to a Shell and Tube Heat Exchanger on Floating Production, Storage, and Offloading 849
44.4.1 Introduction of Shell and Tube Heat Exchangers 849
44.4.2 RCM Process 850
Heat Exchangers Inventory Description 850
Risk Criteria 850
Risk Analysis 850
FEMCA Analysis 850
Function 853
Functional Failure 853
Failure Effect 853
Failure Reason 853
Maintenance Strategy 854
Task Logic Tree 854
Corrective Tasks 854
Scheduled Tasks 854
References 855
Part 6 Fixed Platforms and FPSO 858
45 - Structural Reassessment of Offshore Structures 860
45.1 Introduction 860
45.2 Corrosion Model and Crack Defects Analysis 860
45.2.1 Corrosion Model 860
45.2.2 Crack Defects Analysis 861
Crack Failure Modes 861
Classified by Stress and Failure Mode 862
Classified by the Position of the Crack 863
Classified by the Shape of the Crack 863
The Effect on the Strength of the Material Due to the Crack 863
45.3 The Residual Ultimate Strength of Hull Structural Components 864
45.3.1 Effects of Crack Defects on Plates and Stiffened Panels 864
Numerical Analysis Method 864
Crack Length and Location Influence 866
Unstiffened Plate with a Transverse Crack Located in the Center (UTC) 866
Unstiffened Plate with a Transversely Oriented Mid-Length Edge Crack (UT1E) 866
Unstiffened Plate with Two Transversely Oriented Mid-Length Edge Cracks (UT2E) 867
Stiffened Plate with a Transverse Crack Located in the Center of the Plate (STC) 867
Stiffened Plate with Two Cracks Located in the Plate and the Stiffener Web (STCW) 867
Conclusion 868
45.3.2 Effects of Localized Corrosion on Plates and Stiffened Panels 868
Numerical Modeling and Analysis Method of Square Plates and Stiffened Panels 868
Effects of Localized Corrosion on Plates 871
Effects of Localized Corrosion on Stiffened Panels 871
50% Volume Loss at Location P11 872
Corrosion Location P21, P31, and P41 872
Corrosion Locations P22, P32, and P42 873
Corrosion Locations P23, P33, and P43 873
45.4 The Residual Ultimate Strength of Hull Structures with Crack and Corrosion Damage 873
45.4.1 Analysis Method of Ultimate Strength 874
45.4.2 Modeling 875
45.4.3 Residual Ultimate Strength with Crack Damage 875
46.4.4 Residual Ultimate Strength with Corrosion Damage 879
References 881
46 - Time-Dependent Reliability Assessment of Offshore Jacket Platforms 882
46.1 Introduction 882
46.2 The Time-Dependent Reliability Model for the Jacket Platform 883
46.3 Probability Model for Resistance of the Jacket Platform 887
46.3.1 Base Shear Capacity 887
46.3.2 Probability Model of the Initial Base Shear Capacity 888
46.3.3 Degradation of the Base Shear Capacity under Corrosion Effect 889
Corrosion Model 889
Corrosion Effect on the Base Shear Capacity 893
46.4 Probability Model for Load Effect of the Jacket Platform 893
46.4.1 Parameter Probability Models of Typhoon Load 893
46.4.2 Load Effect of the Jacket Platform under Typhoon Load 894
46.4.3 The Probability Model of the Load Effect 895
46.5 Time-Dependent Reliability Assessment 895
46.5.1 The Example Platform 895
46.5.2 Probability Model for Resistance of the Jacket Platform 896
FE Model and the Base Shear Capacity of the Example Jacket Platform 896
Probability Model of the Initial Base Shear Capacity 896
Degradation of the Base Shear Capacity under Corrosion Effect 898
46.5.3 Probability Model for Load Effect of the Jacket Platform 898
46.5.4 Time-Dependent Reliability Assessment Results of the Platform 901
46.6 Conclusion 902
References 903
47 - Reassessment of Jacket Structure 906
47.1 General 906
47.2 Modeling 907
47.2.1 Structural Model 907
47.2.2 Metocean Data 907
47.2.3 Foundation Model 908
47.2.4 Corrosion Rate Model 909
47.3 Pushover Analysis 911
47.3.1 Ultimate Strength Analysis 912
47.3.2 Reserve Strength Ratio 913
47.3.3 Incremental Wave Theory 913
47.4 Corrosion Effect on the Jacket Structure 914
47.5 Comparing Corrosion Effect 916
47.6 Conclusion 919
References 920
48 - Risk and Reliability Applications to FPSO 922
48.1 General 922
48.2 Risk-Based Classification 923
48.2.1 Applicability of Risk-Based Classification 923
48.2.2 Owner/Operator's Responsibilities 923
48.2.3 Classifications' Responsibilities 924
48.2.4 Submittals and Requirements for Design Verification 924
48.3 Risk-Based Inspection 924
48.3.1 Strengths and Weaknesses of Risk-Based Inspection (Advantages of Risk-Based Inspection) 925
48.3.2 Elements and Procedures of Risk-Based Inspection 926
48.3.3 Methodology of Risk-Based Inspection 927
Qualitative Approach 927
Quantitative Approach 928
Consequence Analysis 929
Analysis of Failure Probability 929
Methods for Determining Inspection Frequency 929
Reliability Updating Based on Inspection Information 932
48.4 Risk-Based Survey 932
48.4.1 Current Practice of Surveys 932
FPSO Surveys (Construction and Installation Surveys) 932
The Surveys for Maintenance of Class 933
48.4.2 The Main Drawbacks of the Current Survey Practice 933
48.4.3 Risk-Based Survey for Maintenance of Class 934
The Survey Process and Its Integration with the Owner's Inspection Program 934
Procedures of Risk-Based Survey 934
Owner's/Operator's Responsibilities 936
Responsibility of the Bureau 937
Further Reading 937
49 - Explosion and Fire Response Analysis for FPSO 938
49.1 Introduction 938
49.2 Accident Causation Analysis 939
49.2.1 Formal Safety Assessment 941
49.3 Phase I: Identification of Dangerous Sources 941
49.3.1 The Structure Function of Fault Tree 942
49.4 Phase II: Risk Assessment and Management 945
49.4.1 Procedure for Fire Risk Assessment and Management 946
49.4.2 Procedure for Explosion Risk Assessment and Management 947
49.5 Phase III: Risk Restraining Project 950
49.6 Examples of Explosion Response of FPSO 952
49.6.1 Introduction 952
49.6.2 Gas Dispersion CFD Simulations 952
Gas Dispersion Scenario 952
The Spatial Distribution of Gas Concentration 954
Actual Gas Cloud and Equivalent Gas Cloud 954
Effect of Leak Rates 955
49.6.3 Gas Explosion CFD Simulation 955
Gas Explosion Scenario 955
49.6.4 Nonlinear Structural Response Analysis 957
Structure Model 957
The Distribution of Structure Stress, Displacement, and Strain 958
The Distribution of Displacement on Main Columns 958
The Displacements on the Midpoint of the Main Girder 959
The Deflection of the Frame 961
49.7 Example of Fire Response of FPSO 962
49.7.1 Fire CFD Simulation 962
Fire Scenario 962
FDS Structure Model 962
FDS Results 964
49.7.2 ANASYS Analysis 966
Temperature Simulation 966
Structure Analysis 966
Results 967
References 968
50 - Asset Integrity Management (AIM) for FPSO 970
50.1 Introduction 970
50.2 Basic Theory for RBM 970
50.3 Risk-Based Inspection 972
50.3.1 Introduction 972
50.3.2 The Main Research Contents 973
50.3.3 Modeling the Risk 973
General 973
Estimation of Risk 974
50.3.4 RBI Process 975
General 975
Data Gathering 975
Screening Assessment 976
Detailed Assessment 977
Risk Evaluation and Optimized Inspection Plan 977
50.4 Safety Integrity Level Assessment 977
50.4.1 Introduction 977
50.4.2 The Main Research Contents 978
50.4.3 Research Method 978
Data Collection and Processing 978
Determine the Level 978
Determine the Level Verification and Test Cycle of SIL 978
50.5 Reliability-Centered Maintenance 979
50.5.1 Introduction 979
50.5.2 The Main Research Contents 981
50.5.3 Research Method 981
Data Gathering 981
Initial Screening 981
Detailed Risk Assessment 981
Establish and Optimize the Maintenance Strategy 982
50.6 Engineering Projects 982
50.6.1 Introduction 982
50.6.2 Screening Analysis 982
High Risk Projects 983
Low Risk Projects 983
50.6.3 Detailed Assessment 984
50.6.4 Risk Mitigation Plan 985
50.6.5 Summary 985
Further Reading 986
Index 988
A 988
B 988
C 989
D 991
E 992
F 993
G 995
H 995
I 996
J 997
K 997
L 997
M 998
N 998
O 999
P 1000
Q 1001
R 1001
S 1003
T 1006
U 1006
V 1007
W 1007
Y 1008