The nature of stresses in a giant static granular column

We systematically investigate the mean pressure measurements at the bottom of a giant static granular column. If a constant overload is placed on top of the bed, the pressure observed displays linearity in overload and nonmonotonic in column height. This result is in contradiction with the classical Janssen model. However it is in good agreement with the oriented stress linearity (OSL) model which reveals a local, linear relation between stress components. We conclude that the OSL model works well not only in a tiny static granular column but also in a giant static granular column.