Mechanics of Unsaturated Geomaterials

This book provides a sound basis in the challenging area of the mechanics of unsaturated geomaterials. The objective is to supply the reader with an exhaustive overview starting from the basics and covering the most recent theories and applications (i.e. natural disasters, nuclear waste disposal, oil and agriculture productions). The presentation of the fundamental concepts is based on an interdisciplinary approach, in the areas of soil, rock and cement-based material mechanics.

Table of Contents:
Preface xv Lyesse LALOUI PART I. FUNDAMENTAL CONCEPTS 1 Chapter 1. Basic Concepts in the Mechanics and Hydraulics of Unsaturated Geomaterials 3 Alessandro TARANTINO 1.1. Water retention mechanisms in capillary systems 4 1.2. Water retention behavior of geomaterials 9 1.3. Water retention mechanisms in geomaterials and the concept of suction 11 1.4. Water flow in capillary systems 18 1.5. Mechanical interactions at the microscale 20 1.6. Microscopic interpretation of volumetric“collapse “ and shear strength 23 1.7. Bibliography 27 Chapter 2. Mechanics of Unsaturated Soils 29 Lyesse LALOUI, Mathieu NUTH and Bertrand FRANCOIS 2.1. Introduction 29 2.2. Stress states 30 2.3. Thermo-hydro-mechanical behavior of unsaturated soils 31 2.4. Effective stress in unsaturated soils 39 2.5. A coupled THM constitutive framework for unsaturated soils 43 2.6. Conclusion 51 2.7. Bibliography 51 Chapter 3. Desiccation Cracking of Soils 55 Herve PERON, Lyesse LALOUI, Liang-Bo HU and Tomasz HUECKEL 3.1. Introduction 55 3.2. Physical processes involved in desiccation cracking of soils 56 3.3. Experimental characterization of desiccation process in soils and its controlling variables 69 3.4. Scenarios of soil desiccation crack pattern formation 74 3.5. Conclusion 79 3.6. Bibliography 80 PART II. EXPERIMENTAL CHARACTERIZATION 87 Chapter 4. Experimental Techniques for Unsaturated Geomaterials 89 Pierre DELAGE 4.1. Introduction 89 4.2. Techniques for controlling suction 90 4.3. Techniques for measuring suction 94 4.4. Mechanical testing devices 97 4.5. Concluding remarks 104 4.6. Bibliography 105 Chapter 5. New Experimental Tools for the Characterization of Highly Overconsolidated Clayey Materials in Unsaturated Conditions 113 Simon SALAGER, Alessio FERRARI and Lyesse LALOUI 5.1. Introduction 113 5.2. Sorption bench 114 5.3. High pressure THM oedometric cell 118 5.4. High pressure and high temperature THM triaxial cell 122 5.5. Conclusions 126 5.6. Bibliography 126 Chapter 6. Field Measurement of Suction, Water Content and Water Permeability 129 Alessandro TARANTINO 6.1. Direct measurement of suction 129 6.2. Indirect measurement of suction 136 6.3. Measurement of water content 140 6.4. Field measurement of water permeability 150 6.5. Bibliography 151 PART III. THEORITICAL DEVELOPMENTS 155 Chapter 7. Hydromechanical Coupling Theory in Unsaturated Geomaterials and Its Numerical Integration 157 Robert CHARLIER, Jean-Pol RADU, Pierre GERARD and Frederic COLLIN 7.1. Introduction – problems to be treated 157 7.2. Numerical tools: the finite element method 163 7.3. Coupling various problems 176 7.4. Acknowledgment 182 7.5. Bibliography 182 Chapter 8. Conservation Laws for Coupled Hydro-Mechanical Processes in Unsaturated Porous Media: Theory and Implementation 185 Ronaldo I. BORJA and Joshua A. WHITE 8.1. Introduction 185 8.2. Mass and momentum conservation laws 187 8.3. Balance of energy and the effective stress 190 8.4. Formulation of boundary-value problem 193 8.5. Numerical example 198 8.6. Summary and conclusions 205 8.7. Acknowledgements 206 8.8. Bibliography 206 Chapter 9. Strain Localization Modeling in Coupled Transient Phenomena 209 Frederic COLLIN, Yannick SIEFFERT and Rene CHAMBON 9.1. Introduction 209 9.2. Experimental evidence 210 9.3. Regularization techniques 212 9.4. Numerical modeling 215 9.5. Applications 221 9.6. Conclusions 227 9.7. Acknowledgment 228 9.8. Bibliography 228 PART IV. ENGINEERING APPLICATIONS 233 Chapter 10. Modeling Landslides in Partially Saturated Slopes Subjected to Rainfall Infiltration 235 John EICHENBERGER, Mathieu NUTH and Lyesse LALOUI 10.1. Introduction: the hazard of shallow landslides 235 10.2. Physical processes in unsaturated soil slopes 236 10.3. Theoretical framework for unsaturated soils 237 10.4. Numerical modeling of an unsaturated soil slope subjected to rainfall events 242 10.5. Conclusion 249 10.6. Bibliography 249 Chapter 11. Thermally Induced Moisture Transport and Pore Pressure Generation in Nearly Saturated Geomaterials 251 Antony P.S. SELVADURAI 11.1. Introduction 251 11.2. Modeling background 252 11.3. Coupled heat and moisture diffusion 253 11.4. Heat-induced moisture transport in a bentonite-sand mixture 257 11.5. Computational simulations of the behavior of bentonite-sand mixture 260 11.6. THM processes in a porous medium 263 11.7. Computational modeling of the THM processes 265 11.8. Experimental modeling of the THM processes in a cementitious block 267 11.9. Comparison of experimental results and computational estimates 270 11.10. Concluding remarks 272 11.11. Acknowledgments 273 11.12. Bibliography 274 Chapter 12. Mechanics of Unsaturated Geomaterials Applied to Nuclear Waste Storage 279 Antonio GENS 12.1. Introduction 279 12.2. THM phenomena in the near field 282 12.3. Theoretical formulation and coupled analysis 284 12.4. Coupled THM analyses of the unsaturated barrier and adjacent rock 286 12.5. Conclusions 299 12.6. Acknowledgments 300 12.7. Bibliography 300 Chapter 13. Soil–Pipeline Interaction in Unsaturated Soils 303 Dilan ROBERT and Kenichi SOGA 13.1. Introduction 303 13.2. Large-scale physical model experiments 304 13.3. Behavior of unsaturated sands 308 13.4. Numerical modeling of the behavior of unsaturated sands 314 13.5. Numerical modeling of the physical model experiments 319 13.6. Dimensionless force – H/D relationship for pipelines in unsaturated soils 321 13.7. Conclusions 323 13.8. Acknowledgments 324 13.9. Bibliography 324 Chapter 14. Coefficient B, Consolidation, and Swelling in Fine Soils Near Saturation in Engineering Practice 327 Luc BOUTONNIER 14.1. Introduction 327 14.2. Model assumptions 328 14.3. How to determine the model? 342 14.4. Why is it interesting for engineers? 345 14.5. Application to Cubzac-les-Ponts experimental embankment 346 14.6. Conclusion 348 14.7. Bibliography 349 Chapter 15. Geomechanical Analysis of River Embankments 353 Cristina JOMMI and Gabriele DELLA VECCHIA 15.1. Introduction 353 15.2. Design specifications and materials 355 15.3. Coupled hydro-mechanical modeling 361 15.4. Simulation and interpretation of experimental data 367 15.5. Final remarks 371 15.6. Bibliography 373 List of Authors 375 Index 379

About the Author :
Professor Lyesse Laloui is Director of the Laboratory of Soil Mechanics, Swiss Federal Institute of Technology, Lausanne, Switzerland and Adjunct Professor in the Civil and Environmental Engineering Department, Duke University, Durham, USA.