Page 7 - Analysis and Design of Energy Geostructures

Contents vii

6.3 Classification of single energy piles 273
6.4 Temperature variations 274
6.5 Thermally induced vertical strain variations 275
6.6 Thermally induced radial strain variations 277
6.7 Thermally and mechanically induced vertical displacement variations 279
6.8 Thermally and mechanically induced shear stress variations 282
6.9 Thermally and mechanically induced vertical stress variations 287
6.10 Degree of freedom variations 290
References 291
Questions and problems 294

7. Thermomechanical behaviour of energy pile groups 299
7.1 Introduction 299
7.2 Idealisations and assumptions 300
7.3 Classification of energy pile foundations 300
7.4 Temperature variations 301
7.5 Pore water pressure variations 304
7.6 Thermally induced vertical strain variations 306
7.7 Thermally induced stress variations 310
7.8 Effect of number of loaded energy piles on the vertical strain variations 313
7.9 Effect of number of loaded energy piles on the vertical stress variations 315
7.10 Key aspects governing the behaviour of energy pile foundations 319
References 323
Questions and problems 325

Part D Analysis 331

8. Analytical modelling of steady heat and mass transfers 333
8.1 Introduction 333
8.2 Idealisations and assumptions 334
8.3 Heat and mass transfers in pipes 338
8.4 Thermal resistance concept for time-independent solutions 354
8.5 Heat transfer within energy piles and other circular heat exchangers 356
8.6 Heat transfer in energy walls and other plane heat exchangers 366
8.7 Heat transfer analysis through equivalent composite thermal circuits 370
8.8 Heat transfer and storage capacities of energy piles 374
8.9 Required thermally active dimension of energy geostructures 377
8.10 The effectiveness-NTU analysis method for energy geostructures 379
References 380
Questions and problems 383