Unsaturated soils for Asia: proceedings of the Asian Conference on Unsaturated Soils, UNSAT-ASIA 2000, Singapore, 18-19 May 2000

Cover......Page 1 Half Title......Page 2 Title Page......Page 4 Copyright Page......Page 5 Table of Contents......Page 6 Preface......Page 16 Organisation......Page 18 1: Keynote lectures......Page 20 Fundamentals of rockfill collapse......Page 22 Some thoughts and studies on the prediction of slope stability in expansive soils......Page 34 Solar energy and evapotranspiration: A control of the unsaturation state in soils......Page 52 Unsaturated tropical residual soils and rainfall induced slope failures in Malaysia......Page 60 Historical developments and milestones in unsaturated soil mechanics......Page 72 Geotechnical aspects of groundwater recharge in arid regions......Page 88 2: Fundamentals and theoretical developments......Page 102 Prediction of cone-index from the state parameter of unsaturated soils......Page 104 Physical definition of residual water content in unsaturated soils......Page 110 The behaviour of unsaturated porous media in the light of a micromechanical approach......Page 114 Applicability of a general effective stress concept to unsaturated soils......Page 120 A neural network framework for unsaturated soils......Page 126 Study of the influence of adhesion force on deformation and strength of unsaturated soil......Page 132 Application of the effective stress principle to volume change in unsaturated soils......Page 138 CT discrimination of fabric change of unsaturated compacted loess during compression process......Page 144 Generalized pore pressure model considering damage for unsaturated soil......Page 150 Constitutive models for triaxial consolidation and shearing of unsaturated soil......Page 156 Damage function and a masonry model for Loess......Page 162 Change of shear strength due to surface tension and matric suction of pore water in unsaturated sandy soils......Page 166 Three-dimensional elasto-plastic model for unsaturated soils......Page 172 Reconsideration of suction controlled techniques by thermodynamics theory of water in soil......Page 178 Understanding of some behaviour of unsaturated soil by theoretical study on capillary action......Page 182 3.1: Modelling of flow......Page 188 Analysis of non-Darcy flow in unsaturated soils modelled by finite element method......Page 190 A technology for unsaturated zone modelling under variable weather conditions......Page 196 Volume averaged parameters for two-phase flow......Page 202 Application of FE consolidation analysis method to fill-type dams......Page 208 Finite element modelling of geomechanics and geoenvironmental engineering for subsurface systems......Page 214 General partial differential equation solvers for saturated-unsaturated seepage......Page 220 Numerical modelling of soil water plant interaction......Page 226 Water flow in unsaturated soil slopes with horizontal drains......Page 230 Governing equations of unsaturated seepage taking the effects of air flow and volume change into consideration......Page 236 3.2: Modelling of stresses and deformations......Page 240 Using soil diffusion to design slab-on-ground foundations on expansive soils......Page 242 Volume change predictions in expansive soils using a two-dimensional finite element method......Page 250 A numerical model of ground moisture variations with active vegetation......Page 256 A stress-strain relationship to solve the singularity resulting from coupling the yield surfaces of Barcelona model......Page 262 Undrained conditions of unsaturated soil using an integral form of the constraints and full Newton-Raphson procedure......Page 268 Performances of HiSS δl-unsat model for soils under saturated and unsaturated conditions......Page 274 4: Suction measurement techniques......Page 280 A new matric suction calibration curve......Page 282 Comparison of total suction values from psychrometer and filter paper methods......Page 288 Use of a new thermal conductivity sensor for laboratory suction measurement......Page 294 A comparison of in-situ soil suction measurements......Page 300 Comparative measurements with sand box, pressure membrane extractor and pressure plate extractor......Page 306 Suction calibration curve of filter paper made in China......Page 312 Investigation of suction generation in apparatus employing osmotic methods......Page 316 A study of the efficiency of semi-permeable membranes in controlling soil matrix suction using the osmotic technique......Page 322 Response of the IC tensiometer with respect to cavitation......Page 328 5: Soil-water characteristics......Page 334 Mineralogy and microfabric of unsaturated residual soil......Page 336 The use of indicator tests to estimate the drying leg of the soil-water characteristic curve......Page 342 The model of water retention curve considering effects of void ratio......Page 348 A new test procedure to measure the soil-water characteristic curves using a small-scale centrifuge......Page 354 A simple method of determining the soil-water charactistic curve indirectly......Page 360 Preliminary study on soil-water characteristics of two expansive soils......Page 366 Engineering properties of unsaturated soils (volume change and permeability)......Page 372 Soil-water characteristic curves of peaty soils......Page 376 6: Permeability and flow......Page 382 A triaxial permeameter for unsaturated soils......Page 384 An explicit relationship for the average capillary suction at the wetting front of soils......Page 390 A method for determining hydraulic conductivity and diffusivity of unsaturated soils......Page 394 A new laboratory method for the measurement of unsaturated coefficients of permeability of soils......Page 400 Water content and soil suction in the capillary zone......Page 406 Examination of the inverse methods for hydraulic properties of unsaturated sandy soil......Page 412 Grain size and void diameter distributions of sands......Page 418 Investigation of seepage behavior through unsaturated soil......Page 424 Numerical simulation for pore fluid flow through unsaturated soil......Page 428 Impact of surface clogging on artificial recharge......Page 434 Determination of field-saturated hydraulic conductivity in unsaturated soil by the pressure infiltrometer method......Page 440 Hydraulic conductivity measurements in two unsaturated soils of Querétaro Valley, Mexico......Page 446 Temperature effects on water retention and water permeability of an unsaturated clay......Page 452 Measuring hydraulic properties for unsaturated soils with unsteady method......Page 458 Inverse analysis of in situ permeability test data for determining unsaturated soil hydraulic properties......Page 464 The application of knowledge-based surface flux boundary modelling......Page 470 Influence of some hydraulic parameters on the pore-water pressure distribution in unsaturated homogeneous soils......Page 476 7: Mass transport......Page 482 Experimental studies of salt movement through unsaturated soils......Page 484 Role of unsaturated soil on aqueous diffusion......Page 490 States of saturation and flow as key inputs in modelling the biodegradation of waste refuse......Page 496 Coupled transient heat and moisture flow in unsaturated swelling soil......Page 502 Dispersivity of partially saturated sand estimated by laboratory column test......Page 508 Impact of the 'Alsacian vineyard ingrassed' on nitrate transfer......Page 514 8: Strength and deformation......Page 518 Triaxial testing of laterite soils......Page 520 Mechanism of rain-induced slope failure in residual soils......Page 524 Estimation of the relation between suction and cohesion using unconfined compression tests......Page 528 Study on shear strength and swelling-shrinkage characteristic of compacted expansive soil......Page 534 Shear strength and swelling of compacted partly saturated bentonite......Page 540 Combined effect of fabric, bonding and partial saturation on yielding of soils......Page 546 Suction and strength behaviour of unsaturated calcrete......Page 552 Soil behaviour in suction controlled cyclic and dynamic torsional shear tests......Page 558 Effects of moulding water content on the behaviour of an unsaturated silty sand......Page 564 Laboratory study of loosely compacted unsaturated volcanic fill in Hong Kong......Page 570 Direct shear properties of a compacted soil with known stress history......Page 576 Relationship between shear strength and matric suction in an unsaturated silty soil......Page 582 Analysis of a steep slope in unsaturated pyroclastic soils......Page 588 Shear strength behaviour of unsaturated granite residual soil......Page 594 Triaxial testing of unsaturated samples of undisturbed residual soil from Singapore......Page 600 Shear strength of undisturbed Bukit Timah granitic soils under infiltration conditions......Page 606 9.1: Collapse......Page 612 Collapsibility of Egyptian loess soil......Page 614 Effect of dissolution of calcium sulfate on volume change characteristics of unsaturated......Page 620 Boundary value problems associated with unsaturated soil collapse testing......Page 626 Building on unsaturated fills: Compaction, suction and volume change......Page 632 9.2: Shrinkage and swelling......Page 638 Soil structure influence on the heave reduction factor......Page 640 Vertical swelling of expansive soils under fully and partially lateral restraint conditions......Page 646 Influence of structure and stress history on the drying behaviour of clays......Page 652 Study on the swell properties and soil improvement of compacted expansive soil......Page 658 Effect of mode of wetting on the deformational behavior of unsaturated soils......Page 664 An experimental study of elastic volume change in unsaturated soils......Page 670 The influence of fabric and mineralogy on the expansivity of an Australian residual clay soil......Page 676 Estimation of volume change functions for unsaturated soils......Page 682 On the volume measurement in unsaturated triaxial test......Page 688 Shrinkage behaviour of some tropical clays......Page 694 Effects of compaction on the reduction of undrained strength and stiffness of Cikarang expansive clay due to wetting......Page 700 Evaluation of ground movement using a simple soil suction technique in Western Australia......Page 706 Desiccation cracking of soil layers......Page 712 Analysis of swelling pressure for an expansive soil using the resistance concept......Page 718 Clay stiffness and reactivity derived from clay mineralogy......Page 722 The lateral swelling pressure on the volumetric behaviour of natural expansive soil deposits......Page 728 Engineering characteristics of black cotton soils in Francistown......Page 734 Behaviour of an unsaturated highly expansive clay during cycles of wetting and drying......Page 740 Swelling characteristics of compacted clayey soils related to their wetting curves......Page 746 10.1: Foundations and roads......Page 750 The blocking effect of piles on ground water level in slopes under rainfall......Page 752 Total soil suction regimes near trees in a semi-arid environment......Page 758 Distress caused by heaving of footing and floor slab – A case study in Gaborone......Page 764 Properties of swelling soils in West Java......Page 770 Multistory apartment building on poznań clay – Case history......Page 776 On the bearing capacity of an unsaturated expansive soil basement......Page 782 Measurement of soil pore pressures in the Danish Road Testing Machine (RTM)......Page 788 10.2: Slopes......Page 794 Field measurements of pore-water pressure profiles in residual soil slopes of the Bukit Timah Granite Formation, Singapore......Page 796 Preliminary assessment of slope stability with respect to rainfall-induced slope failures......Page 802 Three-dimensional back analysis of unsaturated soil strength parameters......Page 808 A new slope stability analysis for Shirasu slopes in Japan......Page 814 Rainfall-induced slope failures in Taiwan......Page 820 Suction and infiltration measurement on cut slope in highly heterogeneous residual soil......Page 826 Modelling variables to predict landslides in the south west flank of the Cameroon volcanic line, Cameroon, West Africa......Page 832 Laboratory experiments on initiation of rainfall-induced slope failure......Page 838 On the stability of unsaturated soil slopes......Page 844 Water retention in a steep moraine slope during periods of heavy rain......Page 850 Influence of rainfall sequences on the seepage conditions within a slope: A parametric study......Page 856 The measurement of matric suction in slopes of unsaturated soil......Page 862 Suction measurement for the prediction of slope failure due to rainfall......Page 866 Author index......Page 872