Material identified using the size range shown in Table 1.

Final effective confining pressure after isotropic compression and constant during shearing.

Initial relative density prior to isotropic compression.

State parameter at onset of shearing (i.e. after isotropic compression). Note that the critical state lines in e–p′ space, and hence the state parameters, were interpreted from the final void ratio at the end of each test, but dilation can continue in dense sands beyond 20% axial strain (Been et al., 1991).

Average coordination number at onset of shearing (i.e. after isotropic compression).

Friction parameters obtained from drained triaxial shearing tests performed in this study at three different cell pressures.

Isotropic load–unload–reload (LUR) cycles of cell pressure followed by LUR cycles of deviator stress.

Note: All specimens failed with a concentrated shear zone in shearing.