Modeling swelling soils for disposal barriers

A fully coupled advanced formulation for heat, liquid and gas transfer in unsaturated deforming soils is presented. Balance equations are rooted in the theory of mixtures. A double porosity model, which is believed to be especially relevant when simulating expansive soils, is proposed to characterize the water transfer mechanism. Another relevant feature of the framework developed, is the incorporation of a consistent elastoplastic model to describe stress‐ strain relationships in unsaturated soils. A flexible FE computer program was developed, including an array of alternative numerical strategies and constitutive equations to enhance its capabilities. The experimental results of a hydration and heating experiment performed on confined expansive bentonite were satisfactorily compared with model simulations. # 2000 Elsevier Science Ltd. All rights reserved.

[1]  Hywel Rhys Thomas,et al.  Analysis of coupled heat, moisture and air transfer in a deformable unsaturated soil , 1995 .

[2]  P. Milly,et al.  A mass-conservative procedure for time-stepping in models of unsaturated flow , 1985 .

[3]  S. Irmay,et al.  On the hydraulic conductivity of unsaturated soils , 1954 .

[4]  C. Truesdell,et al.  The Classical Field Theories , 1960 .

[5]  Yoshiaki Yoshimi,et al.  Compression of Partially Saturated Cohesive Soils , 1963 .

[6]  Eduardo Alonso,et al.  Consolidation of unsaturated soils including swelling and collapse behaviour , 1980 .

[7]  David W. Pollock,et al.  Simulation of Fluid Flow and Energy Transport Processes Associated With High‐Level Radioactive Waste Disposal in Unsaturated Alluvium , 1986 .

[8]  H. Saunders.  Book Reviews : The Finite Element Method (Revised): O.C. Zienkiewicz McGraw-Hill Book Co., New York, New York , 1980 .

[9]  Antonio Gens,et al.  ELASTOPLASTIC MODELLING OF PARTIALLY SATURATED SOILS. NUMERICAL MODELS IN GEOMECHANICS. NUMOG III. PROCEEDINGS OF THE 3RD INTERNATIONAL SYMPOSIUM HELD AT NIAGARA FALLS, CANADA, 8-11 MAY 1989 , 1989 .

[10]  Antonio Gens,et al.  A framework for the behaviour of unsaturated expansive clays , 1992 .

[11]  S. Majid Hassanizadeh,et al.  Derivation of basic equations of mass transport in porous media, Part 1. Macroscopic balance laws , 1986 .

[12]  Antonio Gens,et al.  A constitutive model for partially saturated soils , 1990 .

[13]  Alejandro Josa Garcia-Tornel,et al.  Un modelo elastoplástico para suelos no saturados , 1994 .

[14]  J. Carrera,et al.  Numerical formulation for a simulator (CODE_BRIGHT) for the coupled analysis of saline media , 1996 .

[15]  Petrus Antonius Cornelius Raats.  Development of Equations Describing Transport of Mass and Momentum in Porous Media, With Special Reference to Soils , 1965 .

[16]  J. Bear.  Dynamics of Fluids in Porous Media , 1975 .

[17]  M V Villar.  FIRST RESULTS OF SUCTION CONTROLLED OEDOMETER TESTS IN HIGHLY EXPANSIVE MONTMORILLONITE , 1995 .

[18]  John Ewen,et al.  Heating unsaturated medium sand , 1989 .

[19]  Harry G. Poulos,et al.  Analysis of the Settlement of Pile Groups , 1968 .

[20]  S. Majid Hassanizadeh,et al.  Derivation of basic equations of mass transport in porous media, Part 2. Generalized Darcy's and Fick's laws , 1986 .

[21]  M. Celia,et al.  A General Mass-Conservative Numerical Solution for the Unsaturated Flow Equation , 1990 .

[22]  E. L. Matyas,et al.  Volume Change Characteristics of Partially Saturated Soils , 1968 .

[23]  A Gens,et al.  CONSTITUTIVE MODELLING: APPLICATION TO COMPACTED SOILS , 1996 .

[24]  Simon J. Wheeler,et al.  Inclusion of specific water volume within an elasto-plastic model for unsaturated soil , 1996 .

[25]  J. Z. Zhu,et al.  The finite element method , 1977 .

[26]  E E Alonso,et al.  STATE SURFACES FOR PARTIALLY SATURATED SOILS. PROCEEDINGS OF THE ELEVENTH INTERNATIONAL CONFERENCE ON SOIL MECHANICS AND FOUNDATION ENGINEERING, SAN FRANCISCO, 12-16 AUGUST 1985 , 1985 .

[27]  A. Lloret,et al.  EXPERIMENTAL BEHAVIOUR OF HIGHLY EXPANSIVE DOUBLE-STRUCTURE CLAY , 1995 .

[28]  Adrian E. Scheidegger,et al.  The physics of flow through porous media , 1957 .

[29]  D. Fredlund,et al.  STRESS STATE VARIABLES FOR UNSATURATED SOILS , 1977 .