Three dimensional fabric evolution of sheared sand

Granular particles undergo translation and rolling when they are sheared. This paper presents a three-dimensional (3D) experimental assessment of fabric evolution of sheared sand at the particle level. F-75 Ottawa sand specimen was tested under an axisymmetric triaxial loading condition. It measured 9.5 mm in diameter and 20 mm in height. The quantitative evaluation was conducted by analyzing 3D high-resolution x-ray synchrotron micro-tomography images of the specimen at eight axial strain levels. The analyses included visualization of particle translation and rotation, and quantification of fabric orientation as shearing continued. Representative individual particles were successfully tracked and visualized to assess the mode of interaction between them. This paper discusses fabric evolution and compares the evolution of particles within and outside the shear band as shearing continues. Changes in particle orientation distributions are presented using fabric histograms and fabric tensor.

[1]  Kanatani Ken-Ichi.  DISTRIBUTION OF DIRECTIONAL DATA AND FABRIC TENSORS , 1984 .

[2]  Karsten E. Thompson,et al.  Quantitative computer reconstruction of particulate materials from microtomography images , 2006 .

[3]  Gioacchino Viggiani,et al.  Advances in X-ray Tomography for Geomaterials , 2006 .

[4]  G. L. Sivakumar Babu,et al.  Effect of soil variability on reliability of soil slopes , 2004 .

[5]  Masanobu Oda,et al.  Microstructure in shear band observed by microfocus X-ray computed tomography , 2004 .

[6]  Khalid A. Alshibli,et al.  Microscopic Evaluation of Strain Distribution in Granular Materials during Shear , 2006 .

[7]  Kazuo Konagai,et al.  LASER-AIDED TOMOGRAPHY: A TOOL FOR VISUALIZATION OF CHANGES IN THE FABRIC OF GRANULAR ASSEMBLAGE , 1992 .

[8]  Tomaso Aste,et al.  Variations around disordered close packing , 2005 .

[9]  Jean-Pierre Bardet,et al.  Observations on the effects of particle rotations on the failure of idealized granular materials , 1994 .

[10]  T Aste,et al.  Geometrical structure of disordered sphere packings. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[11]  P. W. Rowe.  The stress-dilatancy relation for static equilibrium of an assembly of particles in contact , 1962, Proceedings of the Royal Society of London. Series A. Mathematical and Physical Sciences.

[12]  M. Oda,et al.  Microstructure of shear bands and its relation to the mechanisms of dilatancy and failure of dense granular soils , 1998 .

[13]  T. W. Martin,et al.  Convection in vibrated annular granular beds. , 2005, Physical review. E, Statistical, nonlinear, and soft matter physics.

[14]  Eiichi Fukushima,et al.  High‐pass bird‐cage coil for nuclear‐magnetic resonance , 1988 .

[15]  Ching S. Chang,et al.  Heterogeneous strain and bonded granular structure change in triaxial specimen studied by computer, tomography , 2003 .

[16]  Radiological techniques developed to describe particle packing , 1969 .

[17]  Sia Nemat-Nasser,et al.  Radiographic and microscopic observation of shear bands in granular materials , 2001 .

[18]  R. Chambon,et al.  Void ratio evolution inside shear bands in triaxial sand specimens studied by computed tomography , 1996 .

[19]  Mark R. Lankton,et al.  Shear Band Characterization of Triaxial Sand Specimens Using Computed Tomography , 2004 .

[20]  Takashi Matsushima,et al.  Grain rotation versus continuum rotation during shear deformation of granular assembly , 2003 .

[21]  C.-Y. Kuo,et al.  Automated Determination of the Distribution of Local Void Ratio from Digital Images , 1996 .

[22]  T. Aste,et al.  Investigating the geometrical structure of disordered sphere packings , 2004 .

[23]  Heinrich M. Jaeger,et al.  Signatures of granular microstructure in dense shear flows , 2000, Nature.

[24]  Sliding and rolling constitutive theory for granular materials , 2004 .

[25]  A. Tordesillas,et al.  Incorporating rolling resistance and contact anisotropy in micromechanical models of granular media , 2002 .

[26]  E. Dean,et al.  Specific length and some constitutive models , 1998 .

[27]  S. Sture,et al.  Digital Imaging Techniques for Assessment of Homogeneity of Granular Materials , 1996 .

[28]  W. Brent Lindquist,et al.  Image Thresholding by Indicator Kriging , 1999, IEEE Trans. Pattern Anal. Mach. Intell..

[29]  H. Jaeger,et al.  Visualization of Shear Band in Sand Using Synchrotron Micro-Tomography , 2008 .

[30]  Erfan G. Nezami,et al.  A micromechanical study of rolling and sliding contacts in assemblies of oval granules , 2003 .

[31]  Masanobu Oda,et al.  THE MECHANISM OF FABRIC CHANGES DURING COMPRESSIONAL DEFORMATION OF SAND , 1972 .