Laboratory and Field Testing of Unsaturated Soils

cover-large.gif......Page 1
front-matter......Page 2
Preface: Special Issue on Laboratory and Field Testing of Unsaturated Soils......Page 6
Introduction......Page 8
Surface Tension, Contact Angle, and Hysteresis......Page 9
Stable and Metastable States of Water......Page 10
Homogeneous and Heterogeneous Cavitation......Page 12
Air-Entry......Page 13
Saturation......Page 14
Osmotic Effect of the Porous Ceramic......Page 17
Principle......Page 18
Design of Axis Translation Test Chambers......Page 19
Equilibrium Time......Page 20
High Degrees of Saturation......Page 21
Final Remarks......Page 22
References......Page 23
Introduction......Page 25
Thermocouple Psychrometers......Page 26
Transistor Psychrometer......Page 28
Chilled-Mirror Psychrometer......Page 29
The Filter Paper Method......Page 30
Thermal Conductivity Sensor......Page 32
Electrical Conductivity Sensor......Page 34
Conclusion......Page 35
References......Page 36
Introduction......Page 37
Hanging Water Column......Page 38
Equipment Details......Page 43
Flushing System......Page 45
Axis Translation Technique Limitations......Page 46
Special Devices or Equipments......Page 47
Correcting for Evaporation and Condensation......Page 48
References......Page 50
Introduction......Page 53
Vapour Equilibrium Technique (VET)......Page 54
Osmotic Technique......Page 55
Application in Traditional Laboratory Tests......Page 56
Oedometer Test......Page 57
Triaxial Shear Strength Tests......Page 59
Other Applications......Page 61
Discussion and Conclusions......Page 62
References......Page 64
Introduction......Page 66
Isotropic Loading Rate......Page 67
Cell Liquid Measurement......Page 68
Direct Measurements on the Specimen......Page 69
Resonant Column Systems......Page 71
Bender Element Based Systems......Page 72
General Considerations......Page 73
True Triaxial with Rigid Loading Plates......Page 74
True Triaxial with Flexible Loading Membranes......Page 75
Recent Refinements on True Triaxial Systems......Page 76
Concluding Remarks......Page 77
Acknowledgements......Page 78
References......Page 79
Introduction......Page 81
Soil Water Retention Curves......Page 82
Water Hydraulic Conductivity in Unsaturated Soils......Page 84
Unsteady State Methods......Page 85
Measurement and Prediction of the Hydraulic Conductivity in Unsaturated Swelling-Shrinking Soils......Page 87
Free or Controlled Swelling......Page 88
Lagrangian or Eulerian?......Page 89
Acknowledgements......Page 90
References......Page 91
Introduction......Page 95
Some Examples of the Relationship between Microstructure and Engineering Properties......Page 97
Methods for Microstructural Characterisation of Unsaturated Soils......Page 98
Background, Advantages and Limitations. Sample Treatment......Page 100
MIP?Water Retention Curve Relationships......Page 101
MIP?Water Permeability Relationships......Page 103
MIP for the Estimation of Macroscopic Volume Changes. Monitoring Changes along Hydro-Mechanical Paths......Page 105
Background, Advantages and Limitations......Page 108
ESEM Applications. Monitoring Microstructural Changes Along Hydraulic Paths......Page 109
Summary and Concluding Remarks......Page 111
References......Page 113
Introduction......Page 118
Soil Contamination......Page 119
Waste Disposal......Page 120
Water Retention and Transfer Properties......Page 123
NAPL Retention and Transfer Properties......Page 124
Temperature Effects......Page 127
Gas Permeability......Page 129
Chemical Aspects......Page 132
References......Page 134
Introduction......Page 139
Pre 1950 Tensiometers......Page 140
Tensiometers in the 1970’s and 1980’s......Page 141
Recent Developments in Tensiometers......Page 142
Indirect Measurement of Suction......Page 144
Electrical Conductivity Sensor......Page 145
Filter Paper Measurements......Page 147
Water Content Measurement Using Dielectric Methods......Page 148
Dielectric Permittivity of Aqueous Solution......Page 149
Dielectric Permittivity of Soil (Mixing Models)......Page 150
Transmission Line Equations......Page 151
Propagation Velocity and Apparent Permittivity......Page 152
TDR Applied to Volumetric Water Content Measurement......Page 153
Time at Which the Step Pulse Enters the Soil......Page 155
Time at Which the Step Pulse is Reflected at the Rod Ends......Page 156
Interpreting Reflection Waveform for Bulk Electrical Conductivity (BEC)......Page 157
Waveforms Modelling......Page 158
Effect of Bulk Water Conductivity (BEC)......Page 159
Effect of Temperature......Page 160
Sampling Volume......Page 161
Water Content Measurement Using Capacitance......Page 162
Field Measurement of Water Permeability......Page 163
Conclusions......Page 164
References......Page 165
Introduction......Page 171
Solar Radiation......Page 172
Evaporation......Page 173
Transpiration......Page 174
Direct Measurement......Page 175
Energy Balance Approach......Page 176
Water Balance Approach......Page 177
Direct Measurement: Monticello (US)......Page 178
Energy Balance Approach: Boissy-le-Chãtel (France)......Page 180
Water Balance Approach: Rocky Mountain Arsenal (US)......Page 181
References......Page 184
Introduction......Page 187
Field Monitoring in Weathered Geomaterials in the Far East......Page 188
The Study Site and Ground Conditions......Page 189
Key Results Obtained from Monitoring......Page 190
Responses of Soil Suction to Rainfall......Page 191
Changes of Horizontal Total Stresses......Page 193
Well-graded Moraine......Page 194
Uniformly Graded Silty Sand......Page 196
Alpine Permafrost......Page 198
Centrifuge Modelling of Unsaturated Dense and Loose Fill Slopes......Page 199
Response to Rainfall Infiltration......Page 200
Reliable Suction Measurements in Centrifuge......Page 201
References......Page 202
Introduction......Page 205
Background......Page 206
The Febex Large-Scale Test: Instrument Layout and Long-Term Behaviour......Page 207
Instrument Performance......Page 208
Some Conclusions......Page 210
Field Instrumentation and Results......Page 211
Concluding Remarks......Page 212
References......Page 213