Effect of Water on Elastic and Creep Properties of Self-Standing Clay Films.

We characterized experimentally the elastic and creep properties of thin self-standing clay films, and how their mechanical properties evolved with relative humidity and water content. The films were made of clay montmorillonite SWy-2, obtained by evaporation of a clay suspension. Three types of films were manufactured, which differed by their interlayer cation: sodium, calcium, or a mixture of sodium with calcium. The orientational order of the films was characterized by X-ray diffractometry. The films were mechanically solicited in tension, the resulting strains being measured by digital image correlation. We measured the Young's modulus and the creep over a variety of relative humidities, on a full cycle of adsorption-desorption for what concerns the Young's modulus. Increasing relative humidity made the films less stiff and made them creep more. Both the elastic and creep properties depended significantly on the interlayer cation. For the Young's modulus, this dependence must originate from a scale greater than the scale of the clay layer. Also, hysteresis disappeared when plotting the Young's modulus versus water content instead of relative humidity. Independent of interlayer cation and of relative humidity greater than 60%, after a transient period, the creep of the films was always a logarithmic function of time. The experimental data gathered on these mesoscale systems can be of value for modelers who aim at predicting the mechanical behavior of clay-based materials (e.g., shales) at the engineering macroscopic scale from the one at the atomistic scale, for them to validate the first steps of their upscaling scheme. They provide also valuable reference data for bioinspired clay-based hybrid materials.

[1]  Andreas Walther,et al.  Nacre-mimetics with synthetic nanoclays up to ultrahigh aspect ratios , 2015, Nature Communications.

[2]  H. Damme,et al.  Elastic properties of swelling clay particles at finite temperature upon hydration , 2014 .

[3]  Benoît Carrier.  Effet de l'eau sur les propriétés mécaniques à court et long termes des argiles gonflantes : expériences sur films autoporteurs et simulations moléculaires , 2013 .

[4]  B. Demé,et al.  Investigating the Anisotropic Features of Particle Orientation in Synthetic Swelling Clay Porous Media , 2013, Clays and Clay Minerals.

[5]  R. Pellenq,et al.  ESEM study of the humidity-induced swelling of clay film. , 2013, Langmuir : the ACS journal of surfaces and colloids.

[6]  B. Cabane,et al.  Tactoid Formation in Montmorillonite , 2012 .

[7]  U. Olsson,et al.  Microstructural and Swelling Properties of Ca and Na Montmorillonite: (In Situ) Observations with Cryo-TEM and SAXS , 2012 .

[8]  L. Dormieux,et al.  Poromechanics of partially saturated COx argillite , 2012 .

[9]  Qunfeng Cheng,et al.  Layered nanocomposites inspired by the structure and mechanical properties of nacre. , 2012, Chemical Society reviews.

[10]  A. Giraud,et al.  About the effect of relative humidity on the indentation response of Meuse/Haute–Marne argillite , 2011 .

[11]  Michel Bornert,et al.  Localized deformation induced by heterogeneities in porous carbonate analysed by multi-scale digital image correlation , 2011 .

[12]  B. Cabane,et al.  Ca/Na montmorillonite: structure, forces and swelling properties. , 2010, Langmuir : the ACS journal of surfaces and colloids.

[13]  Michel Bornert,et al.  Multiscale Full‐Field Strain Measurements for Micromechanical Investigations of the Hydromechanical Behaviour of Clayey Rocks , 2010 .

[14]  Franz-Josef Ulm,et al.  Nanogranular origin of concrete creep , 2009, Proceedings of the National Academy of Sciences.

[15]  M. Grédiac,et al.  Assessment of Digital Image Correlation Measurement Errors: Methodology and Results , 2009 .

[16]  Franz-Josef Ulm,et al.  The effect of the nanogranular nature of shale on their poroelastic behavior , 2007 .

[17]  J. Bonnet,et al.  Montmorillonite based artificial nacre prepared via a drying process , 2006 .

[18]  S. Clarke,et al.  Preferred orientation in filtercakes of kaolinite. , 2005, Journal of colloid and interface science.

[19]  B. Teppen,et al.  A Simple Method for Partial Purification of Reference Clays , 2005 .

[20]  Á. F. Cano,et al.  Baseline studies of the clay minerals society source clays: Chemical analyses of major elements , 2001 .

[21]  M. Cates,et al.  Effective elastic properties of solid clays , 2001 .

[22]  Yu-Jun Cui,et al.  The relationship between suction and swelling properties in a heavily compacted unsaturated clay , 1998 .

[23]  R. Harba,et al.  Surface topography and mechanical properties of smectite films , 1997 .

[24]  Franz-Josef Ulm,et al.  Microprestress-Solidification Theory for Concrete Creep. I: Aging and Drying Effects , 1997 .

[25]  T. Boutreux,et al.  Compaction of granular mixtures: a free volume model , 1997 .

[26]  L. Michot,et al.  Mechanism of Adsorption and Desorption of Water Vapor by Homoionic Montmorillonite: 3. The Mg2+, Ca2+, Sr2+ and Ba2+ Exchanged Forms , 1997 .

[27]  Fook Hou Lee,et al.  The role of particle breakage in pile creep in sand , 1996 .

[28]  A. Masion,et al.  Mechanism of Adsorption and Desorption of Water Vapor by Homoionic Montmorillonites: 2. The Li+ Na+, K+, Rb+ and Cs+-Exchanged Forms , 1995 .

[29]  L. Schramm,et al.  Influence of Exchangeable Cation Composition on the Size and Shape of Montmorillonite Particles in Dilute Suspension , 1982 .

[30]  H. Damme,et al.  Photochemical and photocatalytic properties of adsorbed organometallic compounds. 1. Luminescence quenching of tris(2,2'-bipyridine)ruthenium(II) and chromium(III) in clay membranes , 1980 .

[31]  R. Ottewill,et al.  Neutron Diffraction from Clay-Water Systems , 1979 .

[32]  U. Mingelgrin,et al.  A Direct Procedure for Determining the number of Plates in Tactoids of Smectites: The Na/Ca-Montmorillonite Case , 1978 .

[33]  Gholamreza Mesri,et al.  COEFFICIENT OF SECONDARY COMPRESSION , 1974 .

[34]  J. Serratosa.  DEHYDRATION AND REHYDRATION STUDIES OF CLAY MINERALS BY INFRARED ABSORPTION SPECTRA , 1960 .

[35]  L. A. Wood,et al.  Adsorption of Water Vapor by Montmorillonite. II. Effect of Exchangeable Ions and Lattice Swelling as Measured by X-Ray Diffraction , 1952 .

[36]  M. Bauchy,et al.  Creep of Bulk CSH : Insights from Molecular Dynamics Simulations , 2015 .

[37]  D. N. Minh,et al.  Effects of desaturation–resaturation on mudstone , 2007 .

[38]  E. Ben-Naima,et al.  Slow relaxation in granular compaction , 1998 .

[39]  M. Zabat.  Microtexture et proprietes mecaniques de films solides de particules colloidales (smectites) , 1996 .

[40]  P. L. Hall,et al.  Particle orientation distributions and stacking arrangements in size-fractionated montmorillonite measured by neutron and X-ray diffraction , 1983 .

[41]  E. A. Hauser,et al.  STUDIES ON GELATION AND FILM FORMATION OF COLLOIDAL CLAYS. I1 , 1937 .