Proceedings of the 1st Vietnam Symposium on Advances in Offshore Engineering (eBook)

Preface 6
Organisation 8
Organising Committee 8
Chairmen 8
Members 8
International Scientific Committee 9
Chairmen 9
Members 9
Sponsors 11
Gold 11
Silver 12
Bronze 13
Organisers 15
Supporter 15
Acknowledegment 16
Contents 17
Keynote lectures 25
Offshore Wind Energy: Technology Opportunities and Challenges 26
Abstract 26
1 Introduction 26
1.1 Global Concerns in Energy Security and Climate Change 26
1.2 Development Progress of Offshore Wind in the World 27
1.3 Asia Pacific and Vietnam Context and Status 28
2 Opportunities for the Development of Offshore Wind Energy 29
2.1 Advantageous Resource Allowing Potentially Lower Cost of Energy 29
2.2 Security of Sustainable Supply or Both Electricity and Gas 30
2.3 Synergy with or Replacement of Offshore Oil and Gas Platforms 30
2.4 Jobs Creation and Supply Chain Opportunities 31
2.5 Improvement of Environment Quality 32
3 Challenges and Potential Solution Approaches 33
3.1 Offshore Wind Resource Assessment and Forecast 33
3.2 Data Management, Marine Spatial Planning, Governance and Policy 34
3.3 Uncertainties in Cost Reduction and Estimation 35
3.4 Modelling and Design: Coupled Analysis and Risk Allocation 37
3.5 Turbine Components, Technology and Supply Chain 38
3.6 Wind Intermittency and Grid Integration 39
3.7 Project Development, Construction and Contracting 40
4 Conclusion 41
Acknowledgments 42
References 42
A Philosophy for Developing Offshore Geotechnical Engineering Models 46
Abstract 46
1 Introduction 46
2 The Key Contributions of the “4 Gs” 47
2.1 General 47
2.2 Geomorphology 47
2.3 Geology 48
2.4 Geophysics 48
2.5 Geotechnics 50
3 Geotechnical Assessments 50
3.1 General 50
3.2 Geotechnical Fieldwork 50
3.3 Laboratory Testing 50
3.4 Taking Account of Engineering Application 53
3.5 Estimating Appropriate Soil Parameters 54
3.6 Dealing with Imperfection 54
3.7 Dealing with Anomalies 55
3.8 Geotechnical Units 55
4 Integrating Data-Sets 58
5 The Application of Statistics 59
6 Geotechnical Characteristics 60
7 Conclusions 61
Appendix 1: Geotechnical Engineering Model (GEM) Check-List 62
References 63
Site Characterization and Ground Modelling 64
A New Calibration Technique to Improve Data Reduction for Stokoe Resonant Column Test 65
Abstract 65
1 Introduction 65
2 Two Spring Model 66
3 Proposed Calibration Method 67
4 Validation of Calibration Results Using Numerical Analysis 68
5 Summary 70
References 70
Distribution of Escherichia coli in Dredged Marine Soils Collected from Waters Around Peninsular Malaysia: A Relation with Geotechnical Properties 71
Abstract 71
1 Introduction 72
2 Materials and Methods 72
2.1 Dredged Marine Soils 72
2.2 Enumeration of Bacteria 72
2.3 Geotechnical Properties of Dredged Marine Soils 73
3 Results and Discussions 73
3.1 Characterisation of DMS 73
3.2 Relation Between Distribution of E. Coli and DMS Geotechnical Properties 74
4 Conclusions 76
Acknowledgement 76
References 76
Image-Based Modelling of Shelly Carbonate Sand for Foundation Design of Offshore Structures 77
Abstract 77
1 Introduction 77
2 Experimental Tests 78
3 Grain-Scale Characterization 79
4 Numerical Modelling 80
5 Conclusions 81
Acknowledgments 82
References 82
Offshore Geotechnical Properties, A VR/Neural-Interpretation: Part 1 83
Abstract 83
1 Introduction 83
2 Recurrent Neural Networks 84
2.1 Learning Rules 84
2.2 An Application Example 85
3 Virtual Reality 86
3.1 How Does VR Work? 86
3.2 A VR-Perspective of Geo-Vision 87
4 Conclusions 88
References 88
Offshore Geotechnical Properties, A VR/Neural-Interpretation: Part 2 89
Abstract 89
1 Introduction 89
2 Geo-Data 90
2.1 A VR-Perspective of Geo-Vision 93
3 Conclusions 94
References 95
Geotechnical Behaviour and Construction Problems of Sabkha Soil 96
Abstract 96
1 Introduction 96
2 Project Location and Site Characterization 97
2.1 Project Location 97
2.2 Project Site Final Grade Level and Reclamation 97
2.3 Geotechnical and Geophysical Information 97
2.4 Local Geology and Soil Conditions 98
3 Problem Soils and Possible Mitigations 99
4 Approach of Reclamation and Improvement 100
5 CIP Pile Construction Problems 100
6 Concluding Remarks 102
References 102
The Role of Geo-Environmental Factors in Landscape and Visual Assessment for Shallow-Water Offshore Structures 103
Abstract 103
1 Introduction 104
2 Methods 104
2.1 Existing (S)LVIA Framework 104
2.2 Case Study Sites 105
3 Results and Analysis 107
3.1 Proposed New SLVIA Framework, Integrating Geo-Environmental Issues 107
4 Conclusions 108
References 108
An Experimental Evaluation of Characteristics of Ball Penetration Test in Soft Clay 110
Abstract 110
1 Introduction 110
2 Penetration Resistances and Strength Factors 111
3 Experimental Programs 111
3.1 Study Sites 111
3.2 BPT and Other Field Tests 111
4 Test Results and Discussions 112
4.1 Effects of Penetrometer Shape and Size 112
4.2 Influence of Shaft-Ball Area Ratio 113
4.3 Soil Stratification by BPT 113
4.4 Influence of Soil Characteristics 114
5 Conclusions 115
Acknowledgement 115
References 115
Dual-Porosity Model for History Matching and Production Forecast for an Oil Reservoir at Cuu Long Basin, Offshore Vietnam 117
Abstract 117
1 Introduction 117
2 Oil Production Mechanisms in Dual-Porosity Model 118
3 Application of Dual-Porosity Model for an Oil Reservoir X 119
4 Conclusion 122
References 123
Liquefaction Resistance and Post-Cyclic Settlement of Nam O Sand Subjected to Uni-Directional and Multi-Directional Cyclic Shears 124
Abstract 124
1 Introduction 124
2 Test Results and Discussions 125
2.1 Liquefaction Resistance of Nam O Sand Subjected to Uni-Directional and Multi-Directional Cyclic Shears 125
2.2 Post-Cyclic Settlement of Nam O Sand 128
3 Conclusions 129
Acknowledgments 129
References 129
The Use of Pressuremeters in the Marine Environment 130
Abstract 130
1 Pressuremeters and Dilatometers 130
2 Insertion 131
3 Determining Stiffness 132
4 Use Off-Shore 133
5 Concluding Remarks 134
References 135
Advanced Pressuremeter Testing for the Padma Multi-purpose Bridge Development 136
Abstract 136
1 Introduction 136
2 The Application of a C?-? Analysis 137
3 Using the Pushed Probe 138
4 Conclusions 141
Acknowledgements 141
References 141
Geotechnical Performance of Offshore Structures 143
Fractured Reservoirs Modeling by Embedded Fracture Continuum Approach: Field-Scale Applications 144
Abstract 144
1 Introduction 144
2 Embedded Fracture Continuum Approach on Modeling Fractures 145
2.1 Equivalent Poro-Elastic Properties of Fracture Cell 145
2.2 Equivalent Permeability of Fracture Cell 146
3 Primary Depletion Modeling of Fractured Reservoir: Effect of Modeling Fractures Explicitly 147
3.1 Properties of REV Volume 147
3.2 Properties of Grand Fractures 148
3.3 Effect of Modeling Fractures Explicitly 148
4 Conclusions 149
References 149
Evolution of Riser-Soil Stiffness in a Soil Crust Layer 151
Abstract 151
1 Introduction 151
2 Sample Preparation 152
3 Model Pipe 153
4 Model Pipe Test Procedures 153
5 Cyclic Riser Test Data 153
6 Normalized Peak-to-Peak Stiffness 154
7 Conclusion 156
Acknowledgement 156
References 156
Improvement of NT-bar Evaluation in Clays Using Large Deformation FE Method 158
Abstract 158
1 Introduction 158
2 NGI-ADPSoft Constitutive Model 159
3 LDFE Analyses 160
3.1 Validation of NGI-ADPSoft Model in Abaqus/Explicit 160
3.2 Parametric Study 161
4 Concluding Remarks 163
Acknowledgments 163
References 163
Design and Construction of the Waterfront Retaining Wall for Cooling Water Intake Pump Station for Jimah East Power Plant, Malaysia 165
Abstract 165
1 Introduction 165
1.1 Location of the Project and Waterfront Retaining Wall Plan 166
1.2 Site Geology and Subsoil Conditions 166
2 Case Studies on a Rigid Concrete Retaining Wall 167
2.1 FEM Analysis with Plaxis 2D 167
2.2 Input Parameters 167
2.3 A Rigid Concrete Retaining Wall Supported by Pile Foundation (PHC) 167
2.4 A Rigid Concrete Retaining Wall with Soil Improvement (DCM) 168
2.5 FEM Analysis Results 168
3 Design of Double Steel Sheet Pile Retaining Wall 168
3.1 General 168
3.2 Design Criteria 168
3.3 FEM Analysis Results 169
4 Construction and Monitoring 169
4.1 Instrumentation Monitoring 169
4.2 Instrumentation Monitoring 169
5 Conclusions 170
References 171
Examination of Caisson-Type Quay Wall for Resilient Structure by Using 1G Shaking Table Test 172
Abstract 172
1 Introduction 172
2 Experiment Conditions 173
3 Experimental Results 174
4 Discussion of Seismic Intensity Method 175
5 Remarks 178
References 178
Methane Hydrate-Bearing Sand - An Energy Resource? 179
Abstract 179
1 Generality 179
1.1 Identifying Gas Hydrates in Natural Sediments 179
1.2 Gas Hydrate Morphologies in Natural Sediments 180
2 The Roles of Gas Hydrates 180
2.1 Gas Hydrates: An Energy Resource 180
2.2 Gas Hydrates: Geo-Hazards 181
2.3 Gas Hydrates and Climate Change 181
3 Mechanical Behavior of Methane Hydrate Bearing Sediments 182
4 Conclusions 183
Acknowledgements 184
References 184
On the Use of Amour Block-RAKUNA IV in Breakwaters and Coastal Protection Works in Vietnam 185
Abstract 185
1 Introduction 185
2 Introduction 186
3 Stable Characteristics and Economic Efficiency of Armour Block RAKUNA-IV 188
3.1 Stable Characteristics of Armour Block RAKUNA-IV 188
3.2 Cost/Economic Efficiency Comparison with Real Structure - Lach Huyen Port-Hai Phong 189
4 Conclusions 190
References 191
Vibratory Driven Installation of Monopiles – An Experimental Investigation of the Soil-Pile Interaction 192
Abstract 192
1 Introduction 192
2 Experimental Investigation with the Scaled Model Tests 193
2.1 Concept and Set Up 193
2.2 Digital Image Correlation Method 193
2.3 Model Test for the Vibratory Driven Pile Installation 194
2.4 Results and Further Processing 195
3 Conclusion 196
Acknowledgements 197
References 197
Application of a Geomechanical Model to Wellbore Stability Analysis: A Case Study X-Well, Bach Ho Field in Vietnam 198
Abstract 198
1 Introduction 198
2 Analytical Solution for Wellbore Stability of a Deviated Well 199
2.1 Stress Distribution Around a Wellbore 199
2.2 Rock Failure Criteria 199
3 Wellbore Stability Analysis and Discussions 200
4 Conclusion 203
Acknowledgements 203
References 203
Numerical Study of Flint/Boulder Behavior During Pile Driving 204
Abstract 204
1 Introduction 204
2 Finite Element Model 205
3 Results of the Dynamic Analyses 207
4 Conclusions 209
Acknowledgments 209
References 209
Modelling of Soil-Pile Interaction for Monopiles for Offshore Wind Turbines: Back-Calculation of Eigenfrequencies 211
Abstract 211
1 Introduction 211
2 Basis for Assessment 212
3 Sensitivity Study of Structural Parameters 212
4 Soil-Pile Stiffness 213
5 Sensitivity Study of the Soil-Pile Stiffness 214
6 Soil Parameter Uncertainty 214
7 Conclusions 215
References 216
Investigation on Seepage Erosion and Safety Mechanism of Suction Caisson Installation 217
Abstract 217
1 Introduction 217
2 Coupled Fluid-Particle Model 218
3 Numerical Model and Results 219
3.1 Safety Mechanism 220
3.2 Critical Suction 221
4 Conclusion 222
References 223
Analysis of Induced Overconsolidation on Response of Granular Pile Reinforced Soft Ground-Effect of Relative Compressibility 224
Abstract 224
1 Introduction 224
2 Analysis 225
2.1 Stress Transfer During Creep 226
2.2 Net Stresses on Soil and Granular Pile (GP) During Creep 226
2.3 Overconsolidation Ratio (OCR) During Creep 227
2.4 Settlement Reduction Factor During Creep 228
2.5 Results and Discussion 228
3 Conclusions 229
References 230
Impact of Holes in Offshore Pile Foundation on Internal Force Distribution 231
Abstract 231
1 Introduction 231
2 Applied Structural Analysis 231
2.1 Analysis Model 231
2.2 Used Program 234
3 Materials 234
3.1 Concrete 234
3.2 Reinforcement 234
4 Design Load 235
4.1 Dead Load 235
4.2 Wind Load 235
4.3 Wave Load 235
4.4 Current Load 236
5 Results and Discussion 236
6 Conclusion 236
References 237
Numerical Analysis on Behaviours of Winged Monopile Subjected to Cyclic Loading in a Calcareous Ground 238
Abstract 238
1 Introduction 238
2 Triaxial Tests of the Calcareous Sand and FEM Simulation 239
3 Numerical Analysis of Monopiles in Calcareous Sand 240
3.1 Description of Numerical Model 240
3.2 Numerical Results and Discussions 242
4 Concluding Remarks 243
References 244
Scour Around a Subsea Structure with Mudmat: Comparison of Field Data with Laboratory Data 245
Abstract 245
1 Introduction 245
2 Field Data 246
2.1 Seabed Surveys 246
2.2 Metocean Data 246
2.3 Sediment Properties 246
3 Model Scale Laboratory Experiments 247
3.1 Assessment of Shear Stress Amplification Factors 247
3.2 Shallow Scour Experiments 248
4 Comparison of Scour Observations with Predictions 249
5 Conclusions 250
References 251
Offshore Renewable Energy Assessment and Forecast 252
Design of an Offshore Wind Farm Layout 253
Abstract 253
1 Introduction 253
2 Modelling of Multiple Wakes in Wind Farms 254
3 Design Optimum Layout of an 8 MW Offshore Wind Farm 255
4 Conclusions 257
Acknowledgments 257
References 258
Potential Application of Slimhole Drilling Technology to Geothermal Wells in Vietnam 259
Abstract 259
1 Introduction 259
2 Slimhole Drilling Technology 261
3 Electrical Generating Capacity of Slimhole Well 262
4 Conclusions 264
References 264
Numerical Approach for Studying Offshore Wind Power Potential Along the Southern Coast of Vietnam 265
Abstract 265
1 Introduction 265
2 Methodology 266
3 Results 267
4 Summary 269
References 269
The Zoning of Offshore Wind Energy Resources in the Vietnam Sea 270
Abstract 270
1 Introduction 270
2 Method of Wind Energy Resources Assessment and Zoning 271
2.1 A Method of Wind Energy Resources Assessment at High Level 271
3 The Results of Offshore Wind Assessment and Zoning 272
4 Discussion and Conclusion 275
References 275
Pipepline Flow Assurance: A Case Study of Oil with High Paraffin Concentration in Vietnam 277
Abstract 277
1 Introduction 277
2 Analytical Solution for Heat Transfer in Pipeline 278
2.1 Stress Distribution Around a Wellbore 278
2.2 Hydraulic Calculation for Oil and Gas Mixtures 278
3 Case Study for Bach Ho Field 279
3.1 Typical Components of Bach Ho Crude Oil 279
3.2 Case Study for the Pipeline from CPP3 to VSP 01 280
4 Conclusions 282
References 282
Geotechnical Analysis of the Stability and the Seepage for an Artificial Energy Atoll Close to the Belgian Coast 283
Abstract 283
1 Introduction 283
2 Methodology 283
2.1 Site Conditions 283
2.2 Analysis Using the Finite Element Method 284
2.3 Description of the Design Model 285
2.4 Parameter Study 286
3 Conclusion 288
References 288
Research and Development of Wind Power in Vietnam 290
Abstract 290
1 Introduction 290
2 Potential of Wind Energy in Vietnam 291
2.1 Potential of Wind Energy in Onshore 291
2.2 Potential of Wind Energy on Offshore 291
3 Wind Power Development Policies in Vietnam 292
4 Wind Power Projects in Vietnam 293
5 Conclusions 294
References 295
Offshore Wind Power in Vietnam: Lessons Learnt from Phu Quy and Bac Lieu Wind Farms 296
Abstract 296
1 Introduction 296
2 The Process of Implementing Projects 297
2.1 Phu Quy Wind Power Plant 297
2.2 Bac Lieu Wind Farm 298
3 Lessons Learnt 298
3.1 Site Selection Survey 298
3.2 Equipment and Technical Solutions 299
3.3 Power System Connection 299
3.4 Lesson Learnt from Economics, Finance and Project Management 300
4 Discussions 301
References 301
Wind, Wave, Tidal and Current Turbine Systems 302
Analytical Study on a Concentric Cylindrical OWC Wave Energy Converter 303
Abstract 303
1 Introduction 303
2 Mathematical Model 304
2.1 Solution of Boundary Value Problems 304
2.2 Power Take-Off Model 305
3 Hydrodynamic Performance of Dual-Chamber OWC-WEC 306
4 Conclusions 307
References 307
The Mechanism of After-Runner Storm Surge Along the North Coast of Vietnam 309
Abstract 309
1 Introduction 309
2 Data and Methods 310
3 Results and Discussion 310
3.1 The Phenomenon of After-Runner Surge in the Typhoon Kalmaegy 310
3.2 Mechanism of After-Runner Surge in Typhoon Kalmaegy 311
4 Conclusions 314
Acknowledgements 314
References 314
Improved Interface Capturing for Ship Hydrodynamics and Multiphase Flow Simulation 316
Abstract 316
1 Introduction 316
2 VOF Method 317
2.1 Governing Equations 317
2.2 Interface Construction 318
3 Coupling VOF with LS (CLSVOF Method) 319
4 Results and Discussions 319
4.1 An Air Bubble Rising in Stagnant Water 320
4.2 Free Surface Flow Surrounding a Ship Hull 320
5 Concluding Remarks 321
Acknowledgements 322
References 322
Design a Small Direct Drive Wind Power Generator 323
Abstract 323
1 Introduction 323
2 Potential of Wind Energy in Vietnam 324
3 Design of Small Direct Drive Generator 325
3.1 Wind Speed Profile 325
3.2 Optimal Analytical Sizing 325
3.3 Finite Elements Analysis Validation 326
4 Prototype and Experimental Testing Results 327
5 Conclusion 328
References 328
Numerical Investigation of Wave-Current Interaction by Using Smoothed Particle Hydrodynamics 330
Abstract 330
1 Introduction 330
2 Smoothed Particle Hydrodynamics 331
3 Numerical Simulation 332
3.1 Computational Domain 332
3.2 Initial and Boundary Conditions 332
3.3 Simulation 332
4 Results and Discussion 333
4.1 Current Flow 333
4.2 Wave-Current Flow 334
5 Conclusion 335
Acknowledgments 335
References 335
Numerical Simulation of a Wave Energy Converter Using Linear Generator 337
Abstract 337
1 Introduction 337
1.1 Ocean Wave Energy 337
1.2 Wave Energy Conversion Technologies 338
2 Concept Model and Modeling 339
2.1 Concept Model 339
2.2 Governing Equations 339
2.2.1 Linear Wave Theory 339
2.2.2 Buoy’s Motion 339
2.2.3 Electromagnetic Field 341
2.3 Tools and Program Development 342
3 Results and Discussions 342
4 Conclusion 343
References 344
Design of Offshore Foundations 345
Suction Pile Design and Installation Challenges for the Ophir WHP 346
Abstract 346
1 Introduction 346
1.1 Project Introduction 346
1.2 Soil Conditions 346
1.3 Jacket and Platform 347
1.4 Suction Pile Foundation 348
1.5 Paper Outline 348
2 Spud Can-Suction Pile Interaction 348
3 Installation Prediction 350
4 Installation Performance 351
5 Conclusions 351
Acknowledgments 352
References 352
Numerical Analysis of Suction Bucket Foundations Used for Offshore Wind Turbines 353
Abstract 353
1 Introduction 353
2 Numerical Modeling 354
2.1 Cyclic Loading 355
3 Parametric Study 356
4 Monotonic Loading 357
5 Conclusion 358
Acknowledgement 358
References 358
Development of Semi Empirical Method for Predicting Axial Pile Capacity 359
Abstract 359
1 Introduction 359
2 Contribution of N-SPT Above and Below the Pile Tip to the End-Bearing Pile Resistance 360
2.1 A Short Overview on SPT 360
3 Database Construction 361
4 Semi Empirical Analysis 362
4.1 Development of Equation 362
4.2 Influence Zone-Back Computation of Internal Shearing Resistance Angle 362
5 Development of the Proposed Method 363
5.1 Base and Shaft Resistances Factors Based on N-SPT 363
6 Comparison of the Developed Method with Available SPT-Based Methods 364
7 Conclusion 364
Appendix: Case Record Summary (60 Cases) 365
References 365
PISA: Recent Developments in Offshore Wind Turbine Monopile Design 367
Abstract 367
1 Background to PISA Project 367
2 Overview of PISA Project Work Packages 368
2.1 Structure and Timetable 368
2.2 Finite Element Modelling 369
2.3 Field Testing 369
2.4 1D Model 370
2.5 Potential Impact 371
3 Next Steps 371
Acknowledgements 372
References 372
Installation of Suction Anchors in Soft Deepwater Gulf of Guinea and Gulf of Mexico Clays 373
Abstract 373
1 Introduction 373
2 General Suction Pile Experiences in Soft Deepwater Clays 374
3 Suction Anchors in Soft Deepwater Gulf of Mexico Clays 374
4 Comparison with Deepwater Gulf of Guinea Cases 375
5 Conclusions 377
Acknowledgments 378
References 378
Life Cycle Changes in p-y Stiffness for a Conductor Pile Installed in Carbonate Silt 379
Abstract 379
1 Motivation and Background 379
2 Centrifuge Model Study 380
2.1 Test Arrangement 380
2.2 Cyclic Lateral Response 381
3 Concluding Remarks and Future Work 383
Acknowledgements 384
References 384
PREDIN, A Preliminary Design Tool for Offshore Wind Turbine Foundations 386
Abstract 386
1 Introduction 387
2 Description of the General Methodology 387
3 Foundation Design 388
4 Marine Operations Module 389
5 Cost Estimate Module 390
6 Example of Design: Jacket Foundation 390
7 Conclusion 391
References 392
Reliability Based Installation Design of a Suction Caisson in Clay 393
Abstract 393
1 Introduction 393
2 Numerical Model 394
2.1 Parameter Selection 395
2.2 Reliability Based Design 396
3 Results 397
4 Conclusion 398
References 398
Investigation of Vertical Pullout Cyclic Response of Bucket Foundations in Saturated Loose Sand 400
Abstract 400
1 Introduction 400
2 Model Tests 401
2.1 Testing Equipment 401
2.2 Bucket Foundation Models and Test Programs 402
3 Results and Discussions 403
3.1 Vertical Pullout Failure Load 403
3.2 Vertical Accumulated Displacement Under Vertical Cyclic Loads 403
3.3 Variation in Unloading Stiffness 404
4 Conclusions 405
Acknowledgement 405
References 405
Numerical Investigation of Installation Effects on the Cyclic Behaviour of Monopile Foundation Under Horizontal Loading 406
Abstract 406
1 Introduction 406
2 Numerical Simulation of the Cyclic Horizontal Behaviour 407
2.1 Explicit Calculation Concept 407
2.2 FE-Model and Boundary Condition 407
2.3 Result of the Simulation 409
3 Conclusion 411
Acknowledgement 411
References 411
Undrained Penetration Using Rate-Dependent and Strain-Softening Tresca Model for Offshore Geotechnical Problems 412
Abstract 412
1 Introduction 412
2 Integration of IESA and RDSS in RITSS for Undrained Penetration 413
3 Numerical Model for Pipeline and Spudcan Penetration 414
4 Results and Discussion 414
4.1 Pipeline Penetration 414
4.2 Spudcan Penetration 415
5 Conclusion 416
Acknowledgement 417
References 417
Driven Pile Design for Offshore Wind Jacket Structures 418
Abstract 418
1 Introduction 418
2 Pile Axial Capacity 419
3 Cyclic Degradation of Axial Capacity 420
4 Clustering 421
5 Soil-Structure Interaction 422
6 Conclusions 423
Acknowledgements 423
References 424
Ultimate Lateral Resistance of Pile Group in Clayey Soils Against Various Directions of Ground Movement 425
Abstract 425
1 Introduction 425
2 Analysis Boundary Condition of Model 426
3 Effect of Ground Movement Direction on Ultimate Lateral Resistance 427
4 Load Apportionment Ratio of Piles in the Pile Groups 429
5 Conclusions 430
References 431
Influence of Layered Soil Profiles on the Application of p-y Curves for Large Diameter Monopiles 432
Abstract 432
1 Background 432
1.1 3D Finite Element Analysis 433
2 Results and Discussions 435
3 Conclusions 437
References 437
Grouted Connections on Monopiles: A Numerical Study 438
Abstract 438
1 Introduction 438
2 Model Definition 439
2.1 Discretisation, Contact Formulation 440
2.2 Material Properties 441
3 Results 441
4 Conclusions 443
Acknowledgements 443
References 443
Centrifuge Study on the Lateral Loaded Response of the Monopod and Tripod Bucket Foundations in Sand 445
Abstract 445
1 Introduction 445
2 Centrifuge Modelling 446
2.1 Test Programme and Objective 446
2.2 Model Soil 446
2.3 Model Caisson 446
3 Interpretation of Results 447
3.1 Moment-Rotation Angle Response 447
3.2 Rotation Angle Response with Cyclic Loading Cycles 448
4 Conclusions 449
References 450
Suction Pile Relocation, a Numerical Study 451
Abstract 451
1 Introduction 451
2 Finite Element Model 452
2.1 Model Geometry and Mesh 452
2.2 Numerical Results 453
3 Conclusion 456
Reference 456
Design of Offshore Structures 457
Experimental Investigation of Elasticity Effects on Slamming 458
Abstract 458
1 Introduction 458
2 Methodology 459
3 Results and Discussions 460
4 Conclusions 462
Acknowledgements 463
References 463
Hydroelastic Analysis of Modular Floating Barges for Hydrocarbon Storage Facility 465
Abstract 465
1 Introduction 465
2 Problem Definition and Methodology 466
3 Results and Discussions 468
4 Conclusions 470
Acknowledgement 470
References 470
Strength Check for Legs Structure of Jack-Up Platforms in Transit Condition 472
Abstract 472
1 Introduction 472
2 Shake-Motion Analysis of Jack up Rig and Determination of the Inertial Forces Acting on the Legs in Transit Condition 473
3 Load Cases Analyses and Load Combinations to Analyze the Jack-up Rig Leg Structure in Transit Condition 474
4 Algorithm Schema of the Problems to Be Solved to Calculate the Strength of the Legs of Jack up Rig in Transit Condition 474
5 Strength Check of the 400 ft Jack-up Rig Leg Structure in Transit Condition 475
5.1 Input Data 475
5.2 Modelling the Jack up Rig in Transit Condition by Finite Element Method 475
5.3 Results of Strength Check of the 400 ft Jack up Rig Legs in Transit Condition 476
6 Conclusion 478
References 478
Global Analysis for Jack-Up Rig 400 ft in Transit Condition 479
Abstract 479
1 Introduction 479
2 Methodology of Jack-Up Rig Structural Analysis in Transit Condition 480
2.1 Wave Loads and Inertial Forces 480
2.2 Jack-Up Rig Structural Analysis Using FEM 482
2.3 Load Transfer from Boundary Element Model to Finite Element Model 482
3 The General Algorithm Combining FEM and BEM to Analyze Global Structure in Transit Condition 483
4 Application Methodology to Strength Checking for Jack-Up Rig 400 ft Structures in Transit Condition Using ANSYS/AQWA Software 484
4.1 Input Data 484
4.2 Models 484
4.3 Results 484
5 Conclusions 485
References 485
Dynamic Effects of Wave Loads in Analysis to Check Strength and Fatigue for Fixed Steel Jacket Structure 486
Abstract 486
1 Introduction 486
2 One Degree of Freedom and Dynamic Effect 487
3 Multi Degree of Freedom and Dynamic Effect 487
4 Dynamic Effect for Check Fatigue 488
5 Application for Practical Analysis 488
5.1 Input Data 488
5.2 Analysis Results 490
6 Conclusion 491
References 492
Offshore Gas Pipeline Linepack to Improve the Flexibility of System Facilities 493
Abstract 493
1 Introduction 493
2 The Basis of Estimation 494
3 Linepack Flexibility 495
4 Case Study 497
5 Conclusion 498
References 499
Aerodynamic Analysis of a 5 MWStall-Regulated Offshore Vertical Axis Wind Turbine Using Computational Fluid Dynamics 500
Abstract 500
1 Introduction 500
2 MW Offshore VAWT 501
3 CFD Simulation 502
3.1 Methodology 502
3.2 Computational Domain and Boundary Conditions 502
3.3 Grid and Time-Step Criteria 503
4 Results and Discussion 505
Acknowledgements 505
References 505
Fatigue of K-Joints – Review and Outlook 507
Abstract 507
1 Introduction 507
2 Review 508
3 Recent Research 509
3.1 Introduction 509
3.2 Test Program 509
3.3 Test Set-up 509
3.4 Fatigue Test Results for K-Joints Made of RHS 510
3.5 Numerical Investigations 511
4 Conclusions and Outlook 511
References 512
Suitability of Helical Anchors for Mooring a Wave Energy Converting System 513
Abstract 513
1 Introduction 513
2 Experimental Setup 514
3 Determination of the Pull-Out Capacity 515
4 Anchor Behavior Under Cyclic Loading 517
5 Conclusions 518
Acknowledgements 518
References 518
Coupled BEM/hp-FEM Modelling of Moored Floaters 519
1 Introduction 519
2 Coupled Mooring Simulations 520
3 RM3 Test Case: Comparing MooDy and MoorDyn Simulations 521
4 Moored Cylinder Test Case: Validation with MooDy 523
5 Concluding Remarks 524
References 525
The Influence of Flexible Towers on the Dynamics of Offshore Wind Turbine Gravity Base Structures 526
Abstract 526
1 Introduction 526
2 Methodology 527
2.1 Model 527
2.2 Dynamic Amplification Factor 527
2.3 Environmental Conditions 528
2.4 Foundation Rotational Stiffness 528
3 Model Specifications 528
3.1 Structure 528
3.2 Metocean Data and Soil Conditions 529
4 Results and Discussion 530
5 Conclusion 531
Acknowledgements 531
References 531
Design of Stationkeeping System for a 12 MW Semi-submersible Floating Offshore Wind Turbine 533
Abstract 533
1 Introduction 533
2 12 MW Wind Turbine Model 534
3 Numerical Simulation and Environmental Conditions 535
4 Results 537
5 Conclusion 538
Acknowledgment 538
References 538
Tubular, Lattice and Hybrid Steel Turbine Towers for Offshore Wind Energy: A Numerical Investigation 539
Abstract 539
1 Introduction 539
2 Numerical Modelling 541
2.1 Cylindrical Steel Wind Turbine Tower 541
2.2 Lattice Steel Wind Turbine Tower 541
3 Results 542
3.1 Cylindrical Steel Wind Turbine Tower 542
3.2 Lattice Steel Wind Turbine Tower 543
4 Conclusions 543
Acknowledgements 544
References 544
VC4OWT: MATLAB Interface for Vibration Control of Offshore Wind Turbine 545
Abstract 545
1 Introduction 545
2 Finite Element Model of the Offshore Wind Turbine 546
2.1 OTW Structure 546
2.2 Soil-Structure Interaction 546
3 Description of VC4OWT 547
4 A Case Study 548
5 Summary 550
References 550
Safety Assessment of Fixed Steel Offshore Structures When Suffering Over-Design Environmental Loading in Vietnamese Sea Conditions 552
Abstract 552
1 Introduction 552
2 Safety Criterions for Fixed Steel Offshore Structures When Suffering Over-Design Environmental Loadings 553
2.1 Safety Condition According to Fatigue Crack Limitations 553
2.2 Safety Condition According to Fully Plastic States of Cross Sections 553
3 Prediction of Over-Design Environmental Condition Probability and Risk Assessment 554
4 A Vietnamese Application 555
4.1 Input Data 555
4.2 First Stage Fatigue Analysis Results 555
4.3 Fatigue Crack Propagation Analysis and Assessment on Structural Extension Time 556
4.4 Safety Assessment in Extended Life Time 556
5 Conclusion 558
References 558
Comparison Study on Bottom Plate Effect on Single Hydrocarbon Storage Tank Through Decay Test 559
Abstract 559
1 Introduction 559
2 Model Information and Experimental Setup 561
3 Results and Discussions 563
4 Conclusions 564
Acknowledgements 564
References 565
Miscellaneous 566
Heat Transfer in Gas Hydrate Sediment 567
Abstract 567
1 Introduction 567
2 Forming Conditions 568
3 Modeling 569
4 Simulation 569
5 Conclusion 570
Acknowledgements 571
References 571
Lesson Learned from Hydraulic Fracturing Stimulation for Improved Oil Production Rate in the Lower Miocene Reservoir, Offshore Viet Nam 573
Abstract 573
1 Introduction 573
2 Integrated Hydraulic Fracturing Procedure 574
2.1 In-Situ Stresses 574
2.2 Fracture Geometry Model 574
2.3 Material Balance 575
2.4 The Unified Fracture Design (UFD) Approach 575
2.5 Fracture Conductivity 575
3 Pump Schedule 576
4 Conclusions 578
References 579
New Structural Solution for Port Protective Works: Rubble Mound Breakwater Slope 580
Abstract 580
1 Introduction 580
2 Proposing the Innovative Structure 580
3 Technical and Economic Evaluation on the Innovative Structure Solution 582
3.1 Technical Evaluation 582
3.2 Economic Evaluation 583
4 Conclusion 585
References 585
Methodology for Total Reliability Evaluation of the Mooring Lines of Floating Offshore Structures 586
Abstract 586
1 Introduction 586
2 Methodology for Total Reliability Evaluation of the Mooring Lines of Floating Offshore Structures 587
2.1 Reliability Evaluation in Traditional Method 587
2.2 Algorithm Diagram for Reliability Evaluation with Probabilistic Method 588
2.3 Total Reliability Evaluation of Mooring Lines Based on Probabilistic Method 589
3 Application for Reliability of FSO Mooring Lines in Vietnam 591
4 Conclusion 592
References 593
Development of a Safety Drinking Water Disinfection System for Removed Areas in Vietnam Powered by Wind Energy 594
Abstract 594
1 Introduction 594
2 Drinking Water Disinfection System Powered by Wind Energy 595
2.1 Wind Energy in Vietnam 595
2.2 Water Disinfection Technologies 596
2.3 Development a Drink Water Disinfection System Powered by Wind Energy 597
3 Discussions and Conclusions 598
Acknowledgement 599
References 599
Application of Numerical Modeling for the Dyke Erosion in Trieu Do Commune on Thach Han River Basin in Vietnam 600
Abstract 600
1 Introduction 600
2 Material and Method 601
2.1 Data Collection 601
2.2 Description of Model 602
2.3 Mesh Establishment 602
3 Results and Discussion 602
3.1 Calibration and Validation 602
3.2 Scenario Development 603
4 Conclusion 605
References 605
New Structural Solution for Breakwater Combined of Fibre Reinforced Polymer (FRP) Concrete Framework and FRP Concrete Plate Constructed on Soft Soil 606
Abstract 606
1 Introduction 606
2 Proposing New Breakwater Structure Based on FRP Bar and Concrete Frame and Concrete Plate 607
3 Technical Calculation 609
3.1 Input Data 609
3.2 Loads on Structure 610
3.3 Stability Calculation 610
4 Conclusion 611
References 612
Hollow Cylinder Breakwater for Dissipation of Wave Energy to Protect the West Coast of Ca Mau Province in Vietnam 613
Abstract 613
1 Introduction 613
2 Hollow Cylinder Breakwater 614
3 Stability Analysis of Breakwater 615
3.1 Wave Load 615
3.2 Stability Analysis 616
4 Settlement Analysis 617
5 Conclusions 618
References 618
Challenges of Life Extension for Offshore Structures and Foundations 620
Abstract 620
1 Introduction 620
2 Life Extension Process 621
3 Challenges of Life Extension for Offshore Structures 622
3.1 Compliance with Codes and Standards 622
3.2 Ageing Mechanism and Concerns 622
3.3 Lack of Historical Data and Knowledge 622
4 Pile Design for Life Extension 623
4.1 Pile Ageing Effect 623
4.2 Pile Driving Fatigue 623
5 Conclusion 624
Acknowledgements 624
References 625
Correction to: Fractured Reservoirs Modeling by Embedded Fracture Continuum Approach: Field-Scale Applications 626
Correction to: Chapter “Fractured Reservoirs Modeling by Embedded Fracture Continuum Approach: Field-Scale Applications” in: M. F. Randolph et al. (Eds.): Proceedings of the 1st Vietnam Symposium on Advances in Offshore Engineering, LNCE 18, https://doi.org/10.1007/978-981-13-2306-5_15 626
Author Index 627