Cundall,
P. A., and Strack,
O. D. L., 1979, “A Discrete Numerical Model for Granular Assemblies,” Geotechnique, 1, pp. 47–65.

Thornton,
C., and Barnes,
D. J., 1986, “Computer Simulated Deformation of Compact Granular Assemblies,” Acta Mech., 64, pp. 45–61.

Ting,
J. M., Corkum,
B. T., Kauffmann,
C. R., and Greco,
C., 1989, “Discrete Numerical Model for Soil Mechanics,” J. Geotech. Eng., 115, pp. 379–398.

Bathurst,
R. J., and Rothenburg,
L., 1990, “Observations on Stress-Force Fabric Relationships in Idealized Granular Materials,” Mech. Mater., 9, pp. 65–80.

Bardet,
J. P., and Proubet,
J., 1992, “Shear-Band Analysis in Idealized Granular Material,” J. Eng. Mech., 118, pp. 397–415.

Oda, M., Iwashita, K., and Kazama, H., 1997, “Micro-Structure Developed in Shear Bands of Dense Granular Soils and Its Computer Simulation. Mechanism of Dilatancy and Failure,” *IUTAM Symposium on Mechanics of Granular and Porous Materials*, N. A. Fleck and A. C. F. Cocks, eds., Kluwer, Dordrecht, The Netherlands, pp. 353–364.

Thomas,
P. A., and Bray,
J. D., 1999, “Capturing Nonspherical Shape of Granular Media With Disk Clusters,” J. Geotech. Geoenvir. Eng., 125, pp. 169–178.

Thornton,
C., 2000, “Numerical Simulations of Deviatoric Shear Deformation of Granular Media,” Geotechnique, 50, pp. 43–53.

Kruyt,
N. P., and Rothenburg,
L., 2002, “Probability Density Functions of Contact Forces for Cohesionless Frictional Granular Materials,” Int. J. Solids Struct., 39, pp. 571–583.

Goldscheider,
M., 1976, “Grenzbedingung und Fliessregel von Sand,” Mech. Res. Commun., 3, pp. 463–468.

Lade,
P. V., and Kim,
M. K., 1988, “Single Hardening Constitutive Model for Frictional Materials: III. Comparison With Experimental Data,” Comput. Geotech.,6, pp. 31–47.

Christofferson,
J., Mehrabadi,
M. M., and Nemat-Nasser,
S., 1981, “A Micromechanical Description of Granular Material Behavior,” ASME J. Appl. Mech., 48, pp. 339–344.

Walton,
K., 1987, “The Effective Elastic Moduli of a Random Packing of Spheres,” J. Mech. Phys. Solids, 35, pp. 213–226.

Jenkins, J. T., 1988, “Volume Change in Small Strain Axisymmetric Deformations of Granular Material,” *Micromechanics of Granular Materials*, M. Satake and J. T. Jenkins, ed., Elsevier, Amsterdam, pp. 143–152.

Fleck,
N. A., Kuhn,
L. T., and McMeeking,
R. M., 1992, “Yielding of Metal Powder Bonded by Isolated Contacts,” J. Mech. Phys. Solids, 40, pp. 1139–1162.

Storåkers,
B., Fleck,
N. A., and McMeeking,
R. M., 1999, “The Viscoplastic Compaction of Composite Powders,” J. Mech. Phys. Solids, 47, pp. 785–815.

Liao,
C. L., Chan,
T. C., Suiker,
A. S. J., and Chang,
C. S., 2000, “Pressure-Dependent Elastic Moduli of Granular Assemblies,” Int. J. Numer. Analyt. Meth. Geomech., 24, pp. 265–279.

Suiker,
A. S. J., de Borst,
R., and Chang,
C. S., 2001, “Micro-Mechanical Modelling of Granular Material—Part 1: Derivation of a Second-Gradient Micro-Polar Constitutive Theory,” Acta Mech., 149, pp. 161–180.

Suiker,
A. S. J., de Borst,
R., and Chang,
C. S., 2001, “Micro-Mechanical Modelling of Granular Material—Part 2: Plane Wave Propagation in Infinite Media,” Acta Mech., 149, pp. 181–200.

Digby,
P. J., 1981, “The Effective Elastic Moduli of Porous Granular Rock,” ASME J. Appl. Mech., 48, pp. 803–808.

Chang,
C. S., Sundaram,
S. S., and Misra,
A., 1989, “Initial Moduli of Particulated Mass With Frictional Contacts,” Int. J. Numer. Analyt. Meth. Geomech., 13, pp. 629–644.

Liao,
C. L., Chang,
T. P., Young,
D. H., and Chang,
C. S., 1997, “Stress-Strain Relationships for Granular Materials Based on the Hypothesis of Best-Fit,” Int. J. Solids Struct., 34, pp. 4087–4100.

Heyliger,
P. R., and McMeeking,
R. M., 2001, “Cold Plastic Compaction of Powders by a Network Model,” J. Mech. Phys. Solids, 49, pp. 2031–2054.

Redanz,
P., and Fleck,
N. A., 2001, “The Compaction of a Random Distribution of Metal Cylinders by the Discrete Element Method,” Acta Mater., 49, pp. 4325–4335.

Johnson, K. L., 1985, *Contact Mechanics*, Cambridge University Press, London, UK.

Cundall, P. A., 1988, “Computer Simulations of Dense Sphere Assemblies,” *Micromechanics of Granular Materials*, M. Satake and J. T. Jenkins, ed., Elsevier, Amsterdam, pp. 113–123.

Bathurst,
R. J., and Rothenburg,
L., 1988, “Micromechanical Aspects of Isotropic Granular Assemblies With Linear Contact Interactions,” ASME J. Appl. Mech., 55, pp. 17–23.

Torquato, S., 2002, *Random Heterogeneous Materials, Microstructure and Macroscopic Properties*, Springer-Verlag, New York.

Suiker, A. S. J., 2002, *The Mechanical Behavior of Ballasted Railway Tracks*, dissertation, Delft University Press, Delft, The Netherlands (pdf-format available at http://www.library.tudelft.nl/dissertations/).

Alexander,
S., 1998, “Amorphous Solids: Their Structure, Lattice Dynamics and Elasticity,” Phys. Rep., 296, pp. 65–236.

Silbert,
L. E., Ertaş,
D., Grest,
G. S., Halsey,
T. C., and Levine,
D., 2002, “Geometry of Frictionless and Frictional Sphere Packings,” Phys. Rev. E, 65(031304), pp. 1–6.

Edwards,
S. F., 1998, “The Equations of Stress in a Granular Material,” Physica A, 249, pp. 226–231.

Ng,
T. T., and Dobry,
R., 1994, “A Non-linear Numerical Model for Soil Mechanics,” J. Geotech. Eng., 120, pp. 388–403.

Lambe, T. W., and Whitman, R. V., 1969, *Soil Mechanics*, John Wiley and Sons, New York.

Davy, C. A., Fleck, N. A., and Bolton, M. D., 2004, “The Collapse Behavior of a Sugar Aggregate,” submitted, for publication.

Lade,
P. V., and Duncan,
J. M., 1975, “Elastoplastic Stress-Strain Theory for Cohesionless Soil,” J. Geotech. Eng., 101, pp. 1037–1053.

Chen, W. F., and Saleeb, A. F., 1982, *Constitutive Equations for Engineering Materials*, John Wiley and Sons, New York.