The physics of sand castles: maximum angle of stability in wet and dry granular media

This is the authors' abstract. We don't add key points for this paper.

We demonstrate that stability criteria can be used to calculate the maximum angle of stability, θm, of a granular medium composed of spherical particles in three dimensions and circular discs in two dimensions. We apply the results to wet granular material by calculating the dependence of θm on the liquid content of the material. The results are in good agreement with our experimental data.