Proceedings of the 2nd Vietnam Symposium on Advances in Offshore Engineering: Sustainable Energy and Marine Planning (Lecture Notes in Civil Engineering, 208)

This book gathers a selection of refereed papers presented at the 2nd Vietnam Symposium on Advances in Offshore Engineering (VSOE 2021), held in 2022 in Ho Chi Minh City, Vietnam. The book consists of articles written by researchers, practitioners, policymakers, and entrepreneurs addressing the important topic of technological and policy changes intended to promote renewable energies and to generate business opportunities in oil and gas and offshore renewable energy. With a special focus on sustainable energy and marine planning, the book brings together the latest lessons learned in offshore engineering, technological innovations, cost-effective and safer foundations and structural solutions, environmental protection, hazards, vulnerability, and risk management. Its content caters to graduate students, researchers, and industrial practitioners working in the fields of offshore engineering and renewable energies. Preface Organisation Organising Committee Chairmen International Members Local Members International Scientific Committee Coordinators Members Invited Reviewers Organisers Patronages Under the Auspices of Contents Keynote Lectures Data-Driven Ground Models: The Road to Fully-Integrated Site Characterization and Design 1 Introduction 2 Data Integration Aka Ground Models: Trilogy of Geology, Geophysics and Geotechnics 2.1 Ground Models – Definition and Semantics 2.2 Generic Workflow 3 Some Examples of Data-Driven Ground Models 3.1 synCPT 3.2 Co-kriging 3.3 Random Forest 4 Room for Improvements and Novel Developments 4.1 Data Quality, Density, and Quality 4.2 Added Value – Multi-sensor Core Logging 4.3 Added Value – UHR 3D Seismic Surveying 4.4 Blending Seismic Inversion with Machine Learning 4.5 Shear Wave Data: Tying the Knot 5 Summary References Experimental Observations on a Suction Bucket Foundation Under Vertical Pullout Loading 1 Introduction 2 Previous Studies on Pullout Capacity 3 Pullout Capacity According to Drainage Condition 3.1 Model Preparation and Testing 3.2 Results and Discussions 4 Conclusion References Phu Cuong Soc Trang Offshore Wind Farm Development Some Lessons Learnt 1 Offshore Wind Resource in Vietnam 2 Features of Near Shore Windfarms Built to Date in the Mekong Delta Provinces 2.1 Ground Conditions 2.2 Weather Conditions for Installation 2.3 Wind Turbine Foundation Solutions 2.4 Operation and Maintenance Solutions 3 Development of the Phu Cuong Soc Trang Offshore Wind Farm 3.1 Project Background 3.2 Geotechnical Investigation 3.3 Metocean Surveys 3.4 Wind Measurement 3.5 Wind Turbine Foundation Design 3.6 Engagement with Fishing Industry 3.7 Operation and Maintenance 3.8 Policy Support for Offshore FIT in Vietnam 3.9 Conclusions References Planning, Policy and Integration for Sustainable Development of Offshore Wind Energy in Vietnam 2022–2030 1 Introduction 2 Vietnam Wind Resource is Excellent 3 Towards 5 GW of Wind Power Operational at the End of 2021 4 Cost of Wind Power is Rapidly Falling, but FIT is Uncertain 5 Scenarios for Wind Power in Vietnam 6 Variability and Flexibility Needs 7 Infrastructure Requirements 8 Conclusion and Policy Implications References Site Characterization and Ground Modelling A Calculation Model for Borehole Collapse Volume in Deviated Openhole in Formation with Weak Plane 1 Introduction 2 Borehole Stresses 3 Elliptical Wellbore for Collapse Volume Calculation 4 Volume of Borehole Collapse 5 Results and Discussion References A Practical Application Using Industrial Waste for Enhancing the Mechanical Properties of Expansive Soil 1 Introduction 2 Materials and Experimental Programs 2.1 Materials 2.2 Experimental Programs 3 Test Results and Discussion 3.1 Ultimate Shear Strength of Bagasse Fibre Reinforced Soil 3.2 Effects of Bagasse Fibre and Lime on Swelling Potential 3.3 Effects of Bagasse Fibre and Lime on Swelling Pressure 3.4 Effects of Bagasse Fibre and Lime on the Compression Characteristics 4 Conclusion References Dynamic Properties of a Calcareous Sand in UAE 1 Introduction 2 Laboratory Testing 3 Test Results and Discussions 3.1 Shear Strength 3.2 Small Strain Stiffness 3.3 Damping Ratio 3.4 Cyclic Resistance Ratio 4 Summary References Estimation of Damping Factors for a Better Assessment of Offshore Driven Piles Capacity 1 Presentation of the Studied Cases 2 Problem Statement 3 Impact of Damping Variations on Capacity Assessment at End of Drive 4 Impact of Damping Variations on Long-Term Capacity Estimation 5 Expected Damping Factor from the Literature 6 Expected Damping Factors from Local Experience 7 Conclusions and Recommendations References Finite Element Model of Wave Loading on a Soil Seabed Part I: Multi-layered Anisotropic Gassy Soil Conditions 1 Introduction 2 Governing Differential Equations for Multi-layer and Anisotropic Poro-Elastic Soil Conditions 3 Harmonic Approximation of Governing Equations 4 Galerkin Finite Element Formulation 5 Incorporation into a Finite Element Model 6 Example of Wave Loading on a Two-Layered Soil Seabed 7 Conclusions References Finite Element Model of Wave Loading on a Soil Seabed Part II: Heterogeneous Gassy Soil Conditions 1 Introduction 2 Governing Differential Equations for Heterogeneous and Anisotropic Poro-Elastic Soil Conditions 3 Harmonic Approximation of Governing Equations 4 Galerkin Finite Element Formulation 5 Incorporation into a Finite Element Model 6 Example Simulation of Wave Loading on a Buried Pipeline 7 Conclusions References Geotechnical Characteristics of Seabed Deposits at Su Tu Trang Site, Cuu Long Basin, Offshore Vietnam 1 Introduction 2 Field Test Program 2.1 Site Location 2.2 In-Situ and Laboratory Tests 3 Soil Characterization 3.1 Soil Profile 3.2 Overconsolidation Ratio (OCR) 3.3 Undrained Shear Strength (su) 4 Conclusions References Investigation of Long-Term Settlement of Flexible Steel Oil Storage Tanks on Calcareous Sand in UAE 1 Introduction 2 General Tank Foundation and Ground Condition 3 Assessment in Situ Soil Density and Stiffness 4 Settlement Evaluation Using Laboratory Tests 4.1 Measurement of Creep for Calcareous Sand Using Triaxial Test 4.2 Assessment of Cyclic Foundation Settlement 5 Concluding Remarks and Recommendations References Investigation of the Long-Term Cyclic Behaviour of Monopile Foundation by Impact and Vibratory Installation 1 Introduction 2 Numerical Calculation Concept 3 Soil Conditions After the Installation Process 4 Simulation of the Cyclic Loading 4.1 Numerical Model and Load Program 4.2 Material and Parameters for the Constitutive Models 4.3 Validation of the Numerical Results 5 Parameter Study 6 Conclusions References Jack up Spudcan Penetration Prediction for Murmanskaya Platform at X-Block, Nam Con Son Basin, Offshore Vietnam 1 Introduction 2 Theoretical Background 3 Results and Discussion 3.1 Geomorphology Seabed Hazard 3.2 Soil Conditions at Jack up Rig Location 3.3 Footing Penetration Prediction 4 Conclusions References Marine Operability Prediction Using Phase-Resolved Wave-Fields 1 Introduction 2 Concept and Methodology 2.1 Concept 2.2 Methodology 3 Simulation 4 Conclusion References Neural Network Modeling of Shear Wave Velocity of Macau Soils Using SPT and CPT Data 1 Introduction 2 Back Propagation (BP) Neural Network 3 Case Study 4 Analysis Results 4.1 The Model with SPT and Vs 4.2 The Model Between CPT and Vs 4.3 The Model Combining SPT, CPT, and Vs 5 Conclusion References Practical Considerations for Advanced Laboratory Tests to Assist Pile Design for Offshore Wind Projects in Vietnam 1 Introduction 2 ALT Strategy for WTG Piled/Monopile Foundations 2.1 Main Considerations for the Design of Piled/Monopile Foundation 2.2 ALTs for the Design of WTG Piled/Monopile Foundation 2.3 ALT Strategy for WTG Piled/Monopile Foundation 3 Establishing Backbone Stiffness Curve from a Combination of Various ALT Techniques 4 Considerations to Cyclic Tests (ALT-3 Group) 5 Summary References Rock Physics Diagnostic (RPD) as a Value-Added Tool in Site Investigation of the Subsea Characteristics for an Offshore Wind Farm Site in Ca Mau, Vietnam 1 Introduction 2 Rock Physics Diagnostic (RPD) Method 3 Results and Discussion 4 Concluding Remarks References Undrained Shear Strength Assessments for Clay of the Offshore Wind Power Projects in Vietnam 1 Introduction 2 Soil Classification and Physical Properties of Clayey Soil 2.1 Project Site Overview 2.2 Physical Properties of Clayey Soil in Binh Dai 3 Mechanical Properties of Clayey Soil in Binh Dai 3.1 Sample Quality Evaluation 3.2 Undrained Shear Strength from Laboratory Test 3.3 Relation Between Normalised Undrained Shear Strength and IL 3.4 CPTU Interpretation 4 Conclusion References Design of Offshore Foundations and Structures Assessment of the Remaining Safety of Pipelines with Corrosion Defects 1 Introduction 2 Accessment Methods 3 FE Modeling Cases 4 Results and Discussions 4.1 Failure Pressure 4.2 Maximum Von Mises Stress 5 Conclusions References Cantilever Secant Pile Constructed in Sand: Numerical Comparative Study and Design Aids 1 Introduction 2 Methods Employed 2.1 Parametric Study 2.2 Methods and Tools 3 Presentation and Analysis of Results 3.1 Effective Penetration Depth and Design Hints 3.2 Rational Empirical Equations 4 Conclusions References Communication and Control for Remotely Operated Underwater Vehicles 1 Introduction 2 Hull Form of the Remotely Operated Underwater Vehicles 3 Propulsive and Steering System 3.1 Propulsive 3.2 Steering System 4 Communication and Control 4.1 ROV and Float Communication 4.2 Float and Mothership Communication 4.3 Monitoring and Controlling ROV 5 Conclusions References Considerations on the Design of Shellfish Reef Against Coastal Erosion 1 Introduction 2 Methods 2.1 Case Study Site 2.2 Wave Dynamics 2.3 Reef Dynamics 3 Results and Analysis 3.1 Wave Dynamics 3.2 Shellfish Reef Efficiency 4 Discussion and Conclusions References Design and Construction of Nearshore Wind Turbine Foundations: Some Experiences of APECO and FECON 1 Introduction 2 Design of WT Foundations 2.1 Selection of WT Foundations 2.2 Design Codes 2.3 Geotechnical Design 2.4 Some Experiences of APECO 3 A Typical Nearshore Project 3.1 General Information 3.2 Foundation Design 3.3 Foundation Construction 4 Conclusions References Design Considerations for Brushwood Fences Concerning Bathymetry and Fence Locations 1 Introduction 2 Methodology 2.1 Bathymetry and Wave Conditions 2.2 Model Description 3 Results 4 Conclusions References Design of Vibro-Driven Large Diameter Monopiles 1 Introduction 2 Experimental Investigation 2.1 Small Scale Model Tests 2.2 Large Scale Model Tests 3 Numerical Investigation 3.1 Installation Process 3.2 Monopile Under Lateral Loading 4 Design Approach 5 Conclusions References Evaluation of the Wave Damping by a Bamboo Breakwater Applying a Porous Media Model 1 Introduction 2 Governing Equations for Waves in Porous Media 3 Waves Propagating Through a Bamboo Breakwater 3.1 Model Setup 3.2 Influence of Porosity and Bamboo Breakwater Width on Transmission Coefficient 3.3 Effectiveness of Wave Nonlinearity on Wave Transmission Coefficient 4 Concluding Remarks References Study the Influence of Newly Built Constructions on the Wave Field of the Dyke Area from Ben Got to Hoang Chau on Cat Hai Island, Hai Phong, Vietnam 1 Introduction 2 Methodology 2.1 Theoretical Description 2.2 Numerical Model Setup 3 Results and Discussions 4 Conclusions References Estimation of Wave Characteristics from the Measured Pressures on Support Structure of Offshore Wind Turbine 1 Introduction 2 Methodology 2.1 Physical Model 2.2 Theoretical Aspects 3 Results and Discussions 4 Conclusions References Evolving Soil-Conductor Stiffness Due to Multiple-Episode Cyclic Loading 1 Introduction 2 Centrifuge Test Description 3 Results and Discussion 4 Conclusions References Experimental Investigation of Wave Scattering Around a Large Vertical Circular Cylinder 1 Introduction 2 Methodology 2.1 Physical Model 2.2 Phase-Based Harmonic Separation Method 2.3 Scattered Wave Field 3 Results and Discussions 4 Conclusions References Experimental Study on the Flexural Performance of RC Beam Strengthened with CFRP Sheet 1 Introduction 2 Experimental Approach 2.1 Specimens 2.2 Materials 2.3 Test Procedures 3 Results and Discussion 3.1 Experimental Results 3.2 Discussions 4 Conclusion References Investigation of Scour Around Two Side-by-Side Piles with Different Spacing Ratios in Live-Bed 1 Introduction 2 Numerical Method 2.1 Governing Equation of the Flow 2.2 Sediment Transport and Morphodynamic Models 3 Model Validation 4 Results 5 Conclusion References Limitations of Helical Screw Anchors for Offshore Structures 1 Introduction 1.1 Helical Anchors - Background 2 Potential Limitations of Helical Anchors for Offshore Applications 2.1 Estimating Load Capacity Prior to Deployment 2.2 Estimating Installation Torque 2.3 Providing High Quality Offshore Installation 2.4 Load Testing 2.5 Limitations of Empirical Torque-To-Capacity Correlations 3 Summary References Mudmat Foundation Stability on Very Soft Clay - Coupling Analytical and Numerical Analysis for a Platform in Vietnam Water 1 Introduction 2 Project Description and Geotechnical Data 3 Analytical Approach 4 Numerical Approach 5 Conclusions References New Practical Approach to Assess the Robustness and Redundancy of Offshore Structures: Application in Life Extension of Fixed Steel Offshore Platforms 1 Historical Background 2 New Approach 2.1 Robustness and Redundancy of Offshore Structures 2.2 Non-linear Space Frame Structure Analysis 2.3 Automation of USFOS Programs 3 Application Case Study 4 Conclusion References Numerical Investigation on Bearing Capacity of Rigid Footing on Sandy Soils Under Eccentrically Inclined Load 1 Introduction 2 Rigid Plastic Constitutive Equation for Finite Element Method 2.1 Rigid Plastic Constitutive Equation for Solid Elements 2.2 Rigid Plastic Constitutive Equation for Interface Elements 3 Ultimate Bearing Capacity for Inclined Central Load 4 Ultimate Bearing Capacity for Eccentrically Inclined Load 5 Limit Load Space of a Rigid Footing in V-H-MSpace 6 Conclusions References Numerical and Experimental Investigation of Wave Loading on a Monopile Support Structure of Offshore Wind Turbine 1 Introduction 2 Methodology 2.1 Physical Model 2.2 Numerical Model 3 Results and Discussions 3.1 Free Surface Elevation 3.2 Wave Loading on Monopile 4 Conclusions References Offshore Engineering: A Systems Science Perspective 1 System Science 1.1 A System in the Systems Science Perspective 1.2 The Relation Between Objects 1.3 Systems Thinking and Systems Engineering 1.4 Risk Management 2 The Offshore System 2.1 The Enterprise System 2.2 The Offshore Management System 3 Principles of Systems Science as Applied to Offshore Platform Systems 3.1 The Principles of Holism and Emergence 3.2 The Principle of Hierarchy 3.3 The Principle of Interaction 3.4 Complexity 4 Summary and Conclusions References Pile Shape Effects on the p-yCurves of Laterally Loaded Piles in Soft Clay 1 Introduction 2 Methodology and Numerical Parametric Study 2.1 Methodology and Finite Element Model 2.2 Validation of the Finite Element Model 3 Numerical Results and the Proposed p-yCurves Considering Pile Shape Effects 3.1 Pile Shape Effects on p-yCurves 3.2 Proposed p-yCurves for Piles with Different Pile Shapes 4 Limitations 5 Summary and Conclusions References Potential Development of Floating Offshore Wind Turbine in Vietnam Offshore 1 Introduction 2 10 MW Floating Offshore Wind Turbine Concepts 2.1 10 MW Wind Turbine 2.2 Floating Platforms 2.3 Mooring Systems 3 Numerical Simulation 4 Environmental Conditions 5 Results and Discussions 6 Conclusion References Slope Stability and Potential Liquefaction of Tra Vinh Sea Dyke Subjected to Dynamic Loadings 1 Introduction 2 Study Project 3 Numerical Modeling 4 Simulation Results and Discussion 4.1 Slope Stability Results 4.2 Liquefaction Results 5 Conclusion and Recommendation References Stress on the Nozzle of a Steel Vertical Storage Tank 1 Introduction 2 Methodology 3 Results and Discussions 4 Conclusions References Study on Degree of Influence of P-Delta Effects on Strength of Jack-Up Leg Structures in Vietnamese Conditions 1 Introduction 2 Estimation of P-Delta Effects on Jack-Up Structures 2.1 Estimation of P-Delta Effects on Jack-Up Structures Using Simple Models 2.2 Global Structural Analysis Taking into Account P-Delta Effects 2.3 Strength Conditions of Jack-Up Legs Based on AISC Standards 3 A Vietnamese Application 3.1 Input Data 3.2 Analysis Results 4 Discussion References Towards Implementation of Artificial Intelligence in Predicting Pile Driving Blow Counts 1 Introduction 2 Available Data 3 Conventional Versus Data Science Approach 4 Data Cleaning and Feature Engineering 5 Data Transformation 6 Prediction Using Various Basic ML Models 7 Adopted Advanced Machine Learning Model 8 Results, Discussion and Limitations 9 Conclusions and Further Work References Performance of Offshore Foundations and Structures Bearing Capacity of Tall Monopile Offshore Wind Turbine Towers Under Environmental Loading 1 Introduction 2 Bearing Capacity of the Offshore Tower with Stiffeners 2.1 Tower Models 2.2 Stiffeners Mass 2.3 Buckling Analysis of the Tower 3 Conclusions References Installation Effects on Axial Performance of Monopiles in Chalk for Offshore Renewables 1 Introduction 2 Constitutive Model for Chalk 2.1 Nonlocal Integration 2.2 Model Parameters 3 Numerical Simulation of Pile Installation 4 Conclusions References Optimisation of Predictions for Driven Piles Performance in Carbonate Silts for Offshore Structures in the Arabian Gulf 1 Introduction 2 Site Conditions 3 Methodologies Used in Arabian Gulf for Carbonate Sediments 4 Pile Monitoring Measurements 5 Carbonate Silt Response to Driven Pile Foundations 6 Results and Discussions 7 Proposed Framework 8 Conclusions References Revised Soil Damping Using Realistic Pile-Soil Interaction Models 1 Introduction 1.1 Damping Measurements in the Field 1.2 Methodology for Monopile Damping Calculations 1.3 Soil Conditions and Load Levels at Monitored Locations 2 Soil Damping Measurements for North Sea Soils 2.1 Test Description 2.2 Empirical Correlations for Shear Modulus Degradation and Damping Ratio 2.3 Damping Measurements for Cohesionless Soils 2.4 Damping Measurements for Cohesive Soils 3 Monopile Damping Calculations 3.1 Results of Kagawa and Kraft (1980) Analysis 4 Conclusions and Recommendations References Fossil Energy: Technology Opportunities and Challenges Applied Machine Learning and Deep Learning to Predict Oil and Gas Production 1 Introduction 2 Methodology 2.1 Input Data 2.2 Workflow 3 Result and Discussion 3.1 Machine Learning 3.2 Neural Networks and Recurrent Neural Networks 4 Conclusion References Challenges in Cementing Deep Offshore Wells 1 Introduction 2 Materials and Methods 2.1 Materials 2.2 Methods 3 Results and Discussion 3.1 Temperature-thinning Effect Demonstrated via Rheological Measurements 3.2 Temperature-Thinning Effect Demonstrated in HTHP Consistometer 3.3 Performance of Anti-settling Agent at 150 °C 3.4 Performance of Anti-settling Agent at 180 °C 3.5 Performance of Anti-settling Agent at 200 °C 4 Conclusion References Interfacial Tension of Hydrocarbon/Water System with Mixed Anionic Surfactants at High Pressures and Temperatures: Optimization of Alkane Number and Salinity 1 Introduction 2 Methods and Material 2.1 Surfactants 2.2 Mineral Oil 2.3 Interfacial Tension Measurements 2.4 Sample Preparation 3 Experimental Results 3.1 Mixture of Surfactants vs Mineral Oil 3.2 Mixture of Surfactants vs n-Dodecane 4 Conclusions References Temperature Effect on Forecast Gas Production 1 Introduction 2 Methodology 2.1 Enthalpy Balance Temperature Model 2.2 Gray Correlation 3 Result and Discussion 4 Conclusion References Tubing Performance with Different Multiphase Flow Correlations 1 Introduction 2 Methodology 2.1 Fundamental of Nodal Analysis 2.2 Tubing Performance Relationship (TPR) 2.3 Calculation Procedure 2.4 Erorr Estimation 3 Results and Discussion 3.1 Gradient Matching 3.2 Sensitivity Analysis 4 Conclusion References Offshore Renewable Energy Systems Fabrication of Concrete Gravity Foundations as Support Structures for Offshore Wind Turbine Facilities 1 Background 1.1 The Scope of the Study 1.2 The Experience with Offshore Concrete Gravity Structures 1.3 Wind Turbine Concepts Made of Concrete 2 Identification of Site for Fabrication 2.1 Potential Fabrication Site in Vietnam 2.2 Fabrication Dock Requirements 3 Materials and Concrete Quality 4 Discussion of Potential Benefits References Microstructure and Mechanical Properties of Methane Hydrate-Bearing Sand 1 Introduction 2 MH Formation Under Excess-Gas Conditions 2.1 MH Formation Procedure 2.2 MH Morphologies and Pore Habits Under Excess-Gas Conditions 3 MH Under Excess-Water Conditions 3.1 MH Formation Procedure 3.2 MH Morphologies and Pore Habits Under Excess-Water Conditions 4 Mechanical Properties of MHBS 5 Conclusions References Options for Zonation and Grid Integration of Offshore Wind in Vietnam 1 Introduction 2 Methods and Models 2.1 Offshore Wind Potential 2.2 Grid Integration Assessment 3 Result and Discussions 3.1 Offshore Wind Zonation 3.2 Generation Adequacy – Loss of Load Probability 3.3 Transmission Adequacy 4 Conclusions References Preliminary Assessment Potential of Underground Energy Storage for Renewable Energy in Cuu Long Basin, Vietnam 1 Introduction 2 Wind Energy Status in Vietnam 3 Assessment of Underground Storage Potential 3.1 Suitable Geologies for Energy Storage 3.2 Methodology for Assessment of Storage Potential in Porous Formations 4 Preliminary Assessment of Underground Storage Potential in Cuu Long Basin 4.1 Geological Setting 4.2 Potential for Energy Storage in Cuu Long Basin 5 Discussion References Marine Spatial Planning GIS-Based Methods for the Analysis of the Main Ports in Europe 1 Introduction 2 Materials and Methods 2.1 GIS Analysis 3 Results and Discussion 4 Conclusion References Observed Coastal Morphological Changes Associated with Coastal Engineering Works at Loc An Beach, South East Vietnam 1 Introduction 1.1 Study Area 2 Methods 3 Results 3.1 Natural Sand Spit Formation 3.2 Observed Changes After Construction Engineering Works 4 Discussion and Conclusion References Author Index