Preface xix Acknowledgment xxi About the Author xxiii Part 1: Local Analysis 1 1 Introduction 3 1.1 Flexible Pipelines Overview 3 1.2 Environmental Conditions 4 1.3 Flexible Pipeline Geometry 7 1.4 Base Case-Failure Modes and Design Criteria 9 1.5 Reinforcements 10 1.6 Project and Objectives 12 References 12 2 Structural Design of Flexible Pipes in Different Water Depth 15 2.1 Introduction 15 2.

2 Theoretical Models 15 2.3 Comparison and Discussion 24 2.4 Conclusions 34 References 34 3 Structural Design of High Pressure Flexible Pipes of Different Internal Diameter 35 3.1 Introduction References 35 3.2 Analytical Models 37 3.2.1 Cylindrical Layers 37 3.2.

2 Helix Layers 39 3.2.3 The Stiffness Matrix of Pipe as a Whole Helix Layers 40 3.2.4 Blasting Failure Criterion 41 3.3 FEA Modeling Description 42 3.4 Result and Discussion 46 3.5 Design 50 3.

6 Conclusions 54 References 55 4 Tensile Behavior of Flexible Pipes 57 4.1 Introduction 57 4.2 Theoretical Models 58 4.2.1 Mechanical Model of Pressure Armor Layer 58 4.2.2 Mechanical Behavior of Tensile Armor Layer 61 4.2.

3 Overall Mechanical Behavior 63 4.3 Numerical Model 64 4.3.1 Pressure Armor Stiffness 64 4.3.2 Full Pipe 69 4.4 Comparison and Discussion 71 4.5 Parametric Study 77 4.

6 Conclusions 79 References 80 5 Design Case Study for Deep Water Risers 83 5.1 Abstract 83 5.2 Introduction 83 5.3 Cross-Sectional Design 85 5.4 Case Study 87 5.5 Design Result 94 5.6 Finite Elements Analysis 97 5.7 Conclusion 100 References 101 6 Unbonded Flexible Pipe Under Bending 103 6.

1 Introduction 103 6.2 Helical Layer Within No-Slip Range 104 6.2.1 Geometry of Helical Layer 104 6.2.2 Bending Stiffness of Helical Layer 108 6.3 Helical Layer Within Slip Range 109 6.3.

1 Critical Curvature 109 6.3.2 Axial Force in Helical Wire Within Slip Range 111 6.3.3 Axial Force in Helical Wire Within No-Slip Range 112 6.3.4 Bending Stiffness of Helical Layer 114 References 116 7 Coiling of Flexible Pipes 117 7.1 Introduction 117 7.

2 Local Analysis 120 7.2.1 Dimensions and Material Characteristics 120 7.2.2 Tension Test 120 7.2.3 Bending Test 123 7.2.

4 Summary 124 7.3 Global Analysis 126 7.3.1 Modeling 126 7.3.2 Interaction and Mesh 127 7.3.3 Load and Boundary Conditions 128 7.

3.4 Discussion of the Results 128 7.4 Parametric Study 134 7.4.1 Diameter of the Coiling Drum 134 7.4.2 Sinking Distance of the Coiling Drum 135 7.4.

3 Reeling Length 138 7.4.4 The Location of the Bearing Plate 139 7.5 Conclusions 142 References 143 Part 2: Riser Engineering 145 8 Flexible Risers and Flowlines 147 8.1 Introduction 147 8.2 Flexible Pipe Cross-Section 147 8.2.1 Carcass 149 8.

2.2 Internal Polymer Sheath 150 8.2.3 Pressure Armor 150 8.2.4 Tensile Armor 151 8.2.5 External Polymer Sheath 151 8.

2.6 Other Layers and Configurations 152 8.3 End Fitting and Annulus Venting Design 152 8.3.1 End Fitting Design and Top Stiffener (or Bellmouth) 152 8.3.2 Annulus Venting System 153 8.4 Flexible Riser Design 154 8.

4.1 Design Analysis 154 8.4.2 Riser System Interface Design 155 8.4.3 Current Design Limitations 156 References 158 9 Lazy-Wave Static Analysis 159 9.1 Introduction 159 9.2 Fundamental Assumptions 162 9.

3 Configuration Calculation 162 9.3.1 Cable Segment 163 9.3.1.1 Hang-Off Section 163 9.3.1.

2 Buoyancy Section 166 9.3.1.3 Decline Section 166 9.3.2 Boundary-Layer Segment 167 9.3.3 Touchdown Segment 168 9.

3.4 Boundary Conditions 170 9.4 Numerical Solution 171 9.5 Finite Element Model 174 9.5.1 Environment 175 9.5.2 Riser 175 9.

5.3 Boundary Conditions 175 9.6 Comparison and Discussion 175 9.7 Parameter Analysis 180 9.7.1 Effect of Seabed Stiffness 180 9.7.2 Effect of Hang-Off Inclination Angle 182 9.

7.3 Effect of Buoyancy Section Length 185 9.8 Conclusions 187 References 188 10 Steep-Wave Static Configuration 189 10.1 Introduction 189 10.2 Configuration Calculation 190 10.2.1 Touch-Down Segment 191 10.2.

2 Buoyancy Segment 194 10.2.3 Hang-Off Segment 195 10.2.4 Boundary Conditions 195 10.3 Numerical Solution 196 10.4 Comparison and Discussion 198 10.5 Parametric Analysis 203 10.

5.1 Effect of Buoyancy Segment''s Equivalent Outer Diameter 203 10.5.2 Effect of Buoyancy Segment Length 205 10.5.3 Effect of Buoyancy Segment Location 207 10.5.4 Effect of Current Velocity 209 10.

6 Conclusions 212 References 212 Contents ix 11 3D Rod Theory for Static and Dynamic Analysis 213 11.1 Introduction 213 11.2 Nomenclature 215 11.3 Mathematical Model 216 11.3.1 Governing Equations 216 11.3.2 Bending Hysteretic Behavior 220 11.

3.3 Bend Stiffener Constraint 222 11.3.4 Pipe-Soil Interaction 224 11.4 Case Study 225 11.5 Results and Discussion 227 11.5.1 Static Analysis 227 11.

5.2 Dynamic Analysis 231 11.5.2.1 Top-End Region 231 11.5.2.2 Touchdown Zone 233 11.

5.3 Effect of Bend Stiffener Constraint 236 11.5.4 Effect of Bending Hysteretic Behavior 238 11.5.5 Effect of Top Angle Constraint 240 11.6 Conclusions 242 References 243 12 Dynamic Analysis of the Cable-Body of the Deep Underwater Towed System 247 12.1 Introduction 247 12.

2 Establishment of Towed System Dynamic Model 248 12.3 Numerical Simulation and Analysis of Calculation Results 251 12.3.1 The Effect of Different Turning Radius 252 12.3.2 The Effect of Different Turning Speeds 253 12.3.3 Dynamic Analysis of the Towed System with the Change of the Parameters of the Cable 254 12.

3.4 The Effect of the Diameters of the Towed Cable 257 12.3.5 The Effect of the Drag Coefficients of the Towed Cable 257 12.3.6 The Effect of the Added Mass Coefficient of the Towed Cable 261 12.4 Conclusions 263 Acknowledgments 264 References 264 13 Dynamic Analysis of Umbilical Cable Under Interference 267 13.1 Introduction 267 13.

2 Dynamic Model of Umbilical Cable 269 13.2.1 Establishment of Mathematical Model 269 13.2.2 The Discrete Numerical Method for Solving the Lumped Mass Method 271 13.2.3 Calculation of the Clashing Force of Umbilical Cable 277 13.3 The Establishment of Dynamic Simulation Model in OrcaFlex 279 13.

3.1 The Equivalent Calculation of the Stiffness of the Umbilical Cable 279 13.3.2 RAO of the Platform 281 13.3.3 The Choice of Wave Theory 281 13.3.4 Establishment of Model in OrcaFlex 282 13.

4 The Calculation Results 283 13.4.1 The Clashing Force of Interference 283 13.4.2 The Variation of the Effective Tension Under Interference 285 13.4.3 The Variation of Bending Under Interference 287 13.5 Conclusion 291 References 294 14 Fatigue Analysis of Flexible Riser 295 14.

1 Introduction 295 14.2 Fatigue Failure Mode of Flexible Riser 296 14.3 Global Model of Flexible Risers 297 14.3.1 Pipe Element 297 14.3.2 Bending Stiffener 298 14.3.

3 Sea Condition 299 14.3.4 Platform Motion Response 300 14.3.5 Time Domain Simulation Analysis 301 14.4 Failure Mode and Design Criteria 302 14.4.1 Axisymmetric Load Model 302 14.

4.2 Bending Load Model 303 14.5 Calculation Method of Fatigue Life of Flexible Riser 305 14.5.1 Rainflow Counting Method 305 14.5.2 S-N Curve 305 14.5.

3 Miner''s Linear Cumulative Damage Theory 307 14.5.4 Modification of Average Stress on Fatigue Damage 308 14.6 Example of Fatigue Life Analysis of Flexible Riser 309 References 314 15 Steel Tube Umbilical and Control Systems 317 15.1 Introduction 317 15.1.1 General 317 15.1.

2 Feasibility Study 318 15.1.3 Detailed Design and Installation 319 15.1.4 Qualification Tests 320 15.2 Control Systems 320 15.2.1 General 320 15.

2.2 Control Systems 321 15.2.3 Elements of Control System 322 15.2.4 Umbilical Technological Challenges and Solutions 323 15.3 Cross-Sectional Design of the Umbilical 326 15.4 Steel Tube Design Capacity Verification 327 15.

4.1 Pressure Containment 328 15.4.2 Allowable Bending Radius 328 15.5 Extreme Wave Analysis 329 15.6 Manufacturing Fatigue Analysis 330 15.6.1 Accumulated Plastic Strain 330 15.

6.2 Low Cycle Fatigue 331 15.7 In-Place Fatigue Analysis 331 15.7.1 Selection of Sea State Data From Wave Scatter Diagram 332 15.7.2 Analysis of Finite Element Static Model 332 15.8 Installation Analysis 332 15.

9 Required On-Seabed Length for Stability 333 References 334 16 Stress and Fatigue of Umbilicals 337 16.1 Introduction 337 16.2 STU Fatigue Models 338 16.2.1 Simplified Model 339 16.2.1.1 Axial and Bending Stresses 339 16.

2.1.2 Friction Stress 340 16.2.1.3 Si.