Energy Geostructures

Preface xiii Lyesse LALOUI and Alice DI DONNA PART 1. PHYSICAL MODELING OF ENERGY PILES AT DIFFERENT SCALES 1 Chapter 1. Soil Response under Thermomechanical Conditions Imposed by Energy Geostructures 3 Alice DI DONNA and Lyesse LALOUI 1.1. Introduction 4 1.2. Thermomechanical behavior of soils 5 1.2.1. Thermomechanical behavior of clays 6 1.3. Constitutive modeling of the thermomechanical behavior of soils 12 1.3.1. The ACMEG-T model 12 1.4. Acknowledgments 18 1.5. Bibliography 18 Chapter 2. Full-scale In Situ Testing of Energy Piles 23 Thomas MIMOUNI and Lyesse LALOUI 2.1. Monitoring the thermomechanical response of energy piles 23 2.1.1. Measuring strains and temperature along the piles 23 2.1.2. Measuring pile tip compression 27 2.1.3. Monitoring the behavior of the soil 27 2.2. Description of the two full-scale in situ experimental sites 28 2.2.1. Single full-scale test pile 28 2.2.2. Full-scale test on a group of energy piles 31 2.2.3. Testing procedure 32 2.3. Thermomechanical behavior of energy piles 36 2.3.1. General methodology 36 2.3.2. Thermomechanical response of the single test pile 38 2.3.3. Thermomechanical response of a group of energy piles 40 2.4. Conclusions 42 2.5. Bibliography 42 Chapter 3. Observed Response of Energy Geostructures 45 Peter BOURNE-WEBB 3.1. Overview of published observational data sources 45 3.2. Thermal storage and harvesting 46 3.2.1. Overview 46 3.2.2. Energy injection/extraction rates 47 3.2.3. Thermal fields 52 3.3. Thermomechanical effects 58 3.3.1. Overview 58 3.3.2. Structural effects 58 3.3.3. Soil-structure interactions 62 3.4. Summary 65 3.5. Acknowledgments 66 3.6. Bibliography 67 Chapter 4. Behavior of Heat-Exchanger Piles from Physical Modeling 79 Anh Minh TANG, Jean-Michel PEREIRA, Ghazi HASSEN and Neda YAVARI 4.1. Introduction 79 4.2. Physical modeling of pile foundations 80 4.2.1. Boundary conditions 80 4.2.2. Mechanical loading system 81 4.2.3. Monitoring 81 4.2.4. Pile's behavior 82 4.3. Physical modeling of a heat-exchanger pile 83 4.3.1. Experimental setup 83 4.3.2. Mechanical behavior of a pile under thermomechanical loading 85 4.3.3. Heat transfer 89 4.3.4. Soil-pile interface 90 4.3.5. Lessons learned from physical modeling of a heat-exchanger pile 91 4.4. Conclusions 94 4.5. Acknowledgments 94 4.6. Bibliography 94 Chapter 5. Centrifuge Modeling of Energy Foundations 99 John S. MCCARTNEY 5.1. Introduction 99 5.2. Background on thermomechanical soil-structure interaction 100 5.3. Centrifuge modeling concepts 101 5.4. Centrifuge modeling components 101 5.4.1. Centrifuge model fabrication and characterization 101 5.4.2. Experimental setup 103 5.5. Centrifuge modeling tests for semi-floating foundations 105 5.5.1. Soil details 105 5.5.2. Foundation A: isothermal load tests to failure 106 5.5.3. Foundation B: thermomechanical stress-strain modeling 110 5.6. Conclusions 113 5.7. Acknowledgments 113 5.8. Bibliography 114 PART 2. NUMERICAL MODELING OF ENERGY GEOSTRUCTURES 117 Chapter 6. Alternative Uses of Heat-Exchanger Geostructures 119 Fabrice DUPRAY, Thomas MIMOUNI and Lyesse LALOUI 6.1. Small, dispersed foundations for deck de-icing 120 6.1.1. Heat demand and specificities of small foundations 121 6.1.2. Modeling of the pile 122 6.1.3. Results and analysis 126 6.2. Heat-exchanger anchors 131 6.2.1. Technical aspects and possible users 131 6.2.2. Method of investigation 132 6.2.3. Optimizing the heat production 134 6.2.4. Mechanical implications of heat production 135 6.3. Conclusions 136 6.4. Acknowledgments 137 6.5. Bibliography 137 Chapter 7. Numerical Analysis of the Bearing Capacity of Thermoactive Piles Under Cyclic Axial Loading 139 Maria E. SURYATRIYASTUTI, Hussein MROUEH, Sébastien BURLON and Julien HABERT 7.1. Introduction 139 7.2. Bearing capacity of a pile under an additional thermal load 140 7.3. A constitutive law of soil-pile interface under cyclic loading: the Modjoin law 143 7.4. Numerical analysis of a thermoactive pile under thermal cyclic loading 145 7.4.1. Reaction to the upper structure 147 7.4.2. Normal force in the pile 148 7.4.3. Mobilized shaft frictions at the soil-pile interface 148 7.5. Recommendation for real-scale thermoactive piles 150 7.5.1. Effect of different loading rates for the applied mechanical load 150 7.5.2. Effect of thermoactive piles on piled raft foundation 150 7.6. Conclusions 153 7.7. Acknowledgments 153 7.8. Bibliography 154 Chapter 8. Energy Geostructures in Unsaturated Soils 157 John S. MCCARTNEY, Charles J.R COCCIA, Nahed ALSHERIF and Melissa A. STEWART 8.1. Introduction 157 8.2. Thermally induced water flow 159 8.3. Thermal volume change in unsaturated soils 160 8.4. Thermal effects on soil strength and stiffness 161 8.5. Thermal effects on hydraulic properties of unsaturated soils 163 8.6. Thermal effects on soil-geosynthetic interaction 164 8.7. Conclusions 167 8.8. Acknowledgments 167 8.9. Bibliography 167 Chapter 9. Energy Geostructures in Cooling-Dominated Climates 175 Ghassan Anis AKROUCH, Marcelo SANCHEZ and Jean-Louis BRIAUD 9.1. Introduction 175 9.2. Climatic factors and their effects on soil conditions and properties 175 9.3. Saturated and unsaturated soil thermal properties and heat transfer 177 9.4. Impact of soil conditions on energy geostructures performance 179 9.4.1. Laboratory experimental design 179 9.4.2. Numerical modeling 180 9.4.3. Laboratory test and numerical results 183 9.4.4. Modeling the full pile 186 9.5. Full scale tests on energy piles 187 9.6. Conclusions 189 9.7. Acknowledgments 190 9.8. Bibliography 190 Chapter 10. Impact of Transient Heat Diffusion of a Thermoactive Pile on the Surrounding Soil 193 Maria E. SURYATRIYASTUTI, Hussein MROUEH and Sébastien BURLON 10.1. Introduction 193 10.2. Heat transfer phenomenon 194 10.2.1. Soil properties 195 10.2.2. Energy conservation in the transient regime 196 10.3. Numerical modeling of thermal diffusion in a thermoactive pile 197 10.3.1. A two-dimensional model - internal diffusion in the thermoactive pile 198 10.3.2. A three-dimensional model - external diffusion to the surrounding soil 201 10.4. Impact of the long-term thermal operation 202 10.4.1. Groundwater flow effect on the heat diffusion 202 10.4.2. Mechanical durability under thermal cyclic stress 205 10.5. Conclusions 205 10.6. Acknowledgments 207 10.7. Bibliography 208 Chapter 11. Ground-Source Bridge Deck De-icing Systems Using Energy Foundations 211 C. Guney OLGUN and G. Allen BOWERS 11.1. Introduction 211 11.2. Ground-source heating of bridge decks 213 11.3. Thermal processes and evaluation of energy demand for ground-source de-icing systems 214 11.4. Numerical modeling and analysis results 216 11.5. Summary and conclusions 223 11.6. Acknowledgments 223 11.7. Bibliography 224 PART 3. ENGINEERING PRACTICE 227 Chapter 12. Delivery of Energy Geostructures 229 Peter BOURNE-WEBB with contributions from Tony AMIS, Jean-Baptiste BERNARD, Wolf FRIEDEMANN, Nico VON DER HUDE, Norbert PRALLE, Veli Matti UOTINEN and Bernhard WIDERIN 12.1. Introduction 229 12.2. Planning and design 230 12.2.1. Coordination and communication 230 12.2.2. Design management 231 12.2.3. System design redundancy 231 12.2.4. Awareness and skills training 234 12.3. Construction 236 12.3.1. Process quality control 236 12.3.2. Installation details 237 12.4. System integration and commissioning 260 12.5. Summary 261 12.6. Acknowledgments 262 12.7. Bibliography 262 Chapter 13. Thermo-Pile: A Numerical Tool for the Design of Energy Piles 265 Thomas MIMOUNI and Lyesse LALOUI 13.1. Basic assumptions 265 13.2. Mathematical formulation and numerical implementation 266 13.2.1. The load-transfer method 266 13.2.2. Displacements induced by the mechanical load 268 13.2.3. Displacements induced by the thermal load 269 13.3. Validation of the method 270 13.4. Piled-beams with energy piles 271 13.4.1. General method 272 13.4.2. Determination of the integration constants 275 13.4.3. Example of simulation 276 13.5. Conclusions 277 13.6. Acknowledgments 278 13.7. Bibliography 278 Chapter 14. A Case Study: The Dock Midfield of Zurich Airport 281 Daniel PAHUD 14.1. The Dock Midfield 281 14.2. Design process of the energy pile system 282 14.2.1. Pile system concept 282 14.2.2. Problems to solve 283 14.2.3. First calculations 284 14.2.4. Second calculations 285 14.2.5. Third calculations 287 14.2.6. Final simulations using the TRNSYS program 288 14.3. The PILESIM program 288 14.4. System design and measurement points 289 14.5. Measured thermal performances of the system 291 14.6. System optimization and integration 293 14.7. Conclusions 294 14.8. Acknowledgments 295 14.9. Bibliography 295 List of Authors 297 Index 299