How does strain localise in standard triaxial tests on sand: Revisiting the mechanism 20 years on

In this paper we present results from the first experiment on Hostsun HN31 sand using a newly-developed, standard size triaxial cell which allows x-ray tomography during loading. Results are consistent to previous work, however new measurement techniques including improved spatial resolution and Digital Volume Correlation, allow incremental strain fields to be measured. Incremental strain fields after failure reveal a complex structure of localised strain, whose beginnings are found far before the stress peak. This opens some fundamental questions on how to best interpret these fundamental deformation mechanisms in sand from a modelling perspective.