Effect of sample size on the response of DEM samples with a realistic grading

- The triaxial compression behaviour of DEM samples bounded periodically and by rigid walls is compared.
- Samples bounded with rigid walls are stiffer and more dilative.
- The heterogeneity of the rigid-wall samples was reduced with increasing sample size.
- The positions of the critical state lines were sensitive to the sample size.
- The ultimate strength of the material was independent of sample size.