The concept of reference curves for constitutive modelling in soil mechanics

This paper presents a simple concept which can be used for simulating a range of soil mechanics problems. The study is motivated by the observation that many experimental results are commonly described in terms of lines or curves according to a phenomenological approach. Frequently, these relations are based on rather different formulations from one application to another, and in complex forms for some cases. This leads to complications for the calibration of parameters as well as constitutive modelling. Thus, a general framework referred to as “reference curves” has been developed. This framework provides a unique treatment of the macroscopically observed behaviour of clays, sands, and structured materials under isotropic compression, as well as the water retention characteristics of granular materials and geotextiles. Several examples are provided illustrating the good accuracy of models developed with this concept. The proposed framework may be equally applied to any other behaviour where reference lines are easily identifiable from a macroscopic scope, such as some non-linear failure envelopes for granular materials. In addition, we show that the incorporation of the proposed equations into constitutive models is quite straightforward.

[1]  Poul V. Lade,et al.  Relative density effects on drained sand behavior at high pressures , 2005 .

[2]  J. Carter,et al.  A structured Cam Clay model , 2002 .

[3]  Jayantha Kodikara,et al.  Characterisation of geotextiles water retention using a modified capillary pressure cell , 2007 .

[4]  Antonio Gens,et al.  Finite element formulation and algorithms for unsaturated soils. Part I: Theory , 2003 .

[5]  John Burland,et al.  The mechanical behaviour of a reconstituted unsaturated silty clay , 2003 .

[6]  P. Comba,et al.  Part I. Theory , 2007 .

[7]  D. Fredlund,et al.  Soil Mechanics for Unsaturated Soils , 1993 .

[8]  A. Polyanin,et al.  Handbook of Exact Solutions for Ordinary Differential Equations , 1995 .

[9]  Kenneth L. Lee,et al.  Drained Strength Characteristics of Sands , 1967 .

[10]  R. Nova,et al.  An experimental and theoretical study of the behaviour of a calcarenite in triaxial compression , 1995 .

[11]  Tom Lunne,et al.  An oedometer test study on the preconsolidation stress of glaciomarine clays , 2003 .

[12]  Tom Schanz,et al.  Physical Modeling of SWCC for Granular Materials , 2007 .

[13]  A. Schofield,et al.  Critical State Soil Mechanics , 1968 .

[14]  Renato V Clementino,et al.  Discussion of "An oedometer test study on the preconsolidation stress of glaciomarine clays" , 2005 .

[15]  Toshihiro Noda,et al.  Simulation of shear and one-dimensional compression behavior of naturally deposited clays by super/subloading yield surface Cam-clay model , 2005 .

[16]  De’an Sun,et al.  A critical state model for sands dependent on stress and density , 2004 .

[17]  Antonio Gens,et al.  A new modelling approach for unsaturated soils using independent stress variables , 2008 .

[18]  Andrew J. Whittle,et al.  Compression model for cohesionless soils , 1995 .