Experimental Unsaturated Soil Mechanics

These proceedings are a continuation of the series of International Conferences in Germany entitled "Mechanics of Unsaturated Soils." The primary objective is to discuss and understand unsaturated soil behaviour such that engineered activities are made better with times in terms of judgement and quality. We all realise by now that in addition to the knowledge on the classical concepts, it becomes an enormous challenging task to adapt convincing new concepts and present them in such a way that it could be used in engineering practices.

The experimental studies reported primarily focus on the role of microstructure and fabric for the complex coupled hydro-mechanical behaviour of cohesive frictional materials. Several papers consider the relevance of temperature affecting the constitutive behaviour of clays. Common features of state of the art theoretical and numerical approaches, including theory of porous media and mixture theory, intend to describe the complex multi-field problems of fully coupled thermo-hydraulic-mechanical-chemical initial - boundary value problems. Applications include highly toxic waste disposals, slope stability problems and contaminants transport in porous media.

These proceedings would have been not possible without financial support by the German Research Foundation (DFG). We gratefully acknowledge the support of ISSMGE, especially TC6 "Unsaturated Soils".

Inhalt

Microstructure and Fabric.- Influence of Relative Density and Clay Fraction on Soils Collapse.- Microstructure Features in the Behaviour of Engineered Barriers for Nuclear Waste Disposal.- Microstructure of Gypsiferous Crust and Its Importance to Unsaturated Soil Behaviour.- Fabric Changes in Compacted London Clay Due to Variations in Applied Stress and Suction.- Microstructure of a Lime Stabilised Compacted Silt.- Measuring Suction.- Errors in Total Suction Measurements.- Application of a Dew Point Method to Obtain the Soil Water Characteristic.- A Comparative Study of Soil Suction Measurement Using Two Different High-Range Psychrometers.- Determination of the Soil Water Retention Curve with Tensiometers.- Tensiometer Development for High Suction Analysis in Laboratory Lysimeters.- Strength and Dilatancy.- Dilatancy of Coarse Granular Aggregates.- A Laboratory Investigation into the Effect of Water Content on the CBR of a Subgrade soil.- Shear Strength Affected by Suction Tension in Unsaturated Fine Grained Soils?.- Shear Strength Behaviour of Unsaturated Silty Soil.- Experimental Investigation on the Time Dependent Behaviour of a Multiphase Chalk.- Testing Unsaturated Soil for Plane Strain Conditions: A New Double Wall Biaxial Device.- Influence of State Variables on the Shear Behaviour of an Unsaturated Clay.- Effect of Capillary and Cemented Bonds on the Strength of Unsaturated Sands.- Determining the Shear Strength of Unsaturated Silt.- Factors Affecting Tensile Strength Measurement and Modified Tensile Strength Measuring Apparatus for Soil.- The Tensile Strength of Compacted Clays as Affected by Suction and Soil Structure.- Temperature Effects.- Modified Isochoric Cell for Temperature Controlled Swelling Pressure Tests.- Some Aspects of the Effect of the Temperature on the Behaviour of Unsaturated Sandy Clay.- Influence of Temperature on the Water Retention Curve of Soils. Modelling and Experiments.- Thermo-Hydro-Mechanical Behaviour of Compacted Bentonite.- Retention Curves of Two Bentonites at High Temperature.- Volumetric Behaviour - Expansive Materials.- Experimental Study on Shrinkage Behaviour and Prediction of Shrinkage Magnitudes of Residual Soils.- Assessment of Swelling Deformation of Unsaturated Kaolinite Clay.- Suction and Collapse of Lumpy Spoilheaps in Northwestern Bohemia.- Oedometer Creep Tests of a Partially Saturated Kaolinite Clay.- Analysis of the Expansive Clay Hydration under Low Hydraulic Gradient.- Moisture Effects on Argillaceous Rocks.- Retention Behaviour.- Results from Suction Controlled Laboratory Tests on Unsaturated Bentonite - Verification of a Model.- Variation of Degree of Saturation in Unsaturated Silty Soil.- Mechanical Behaviour of Compacted Scaly Clay During Cyclic Controlled-Suction Testing.- Prediction of Soil-Water Characteristic Curve Based on Soil Index Properties.- Water Balance and Effectiveness of Mineral Landfill Covers - Results of Large Lysimeter Test-Fields.- A Retention Curve Prediction for Unsaturated Clay Soils.- Unsaturated-Zone Leaching and Saturated-Zone Mixing Model in Heterogeneous Layers.- Prediction of SWCC for Coarse Soils Considering Pore Size Changes.- The Influence of the Pore Fluid on Desiccation of a Deformable Porous Material.- Determination of the Soil Water Retention Curve and the Unsaturated Hydraulic Conductivity from the Particle Size Distribution.- Field Applications.- Earthquake-Induced Mudflow Mechanism from a Viewpoint of Unsaturated Soil Dynamics.- Plate-Load Tests on an Unsaturated Lean Clay.- Selfsealing Barriers of Clay/Mineral Mixtures. TheSB Project at the Mont Terri Rock Laboratory.- Preferential Water Movement in Homogeneous Soils.- Compaction Properties of Agricultural Soils.- Bearing Capacity of Model Footings in Unsaturated Soils.- Influence of Soil Suction on Trench Stability.