Technische Universität München, Germany
Absract. When a granular material is poured on top of a surface, the formation of a cone-like pile is observed. This paper concerns with the factors that affect the size of the angle, that the pile makes with the ground, also known as angle of repose. The field of Physics, that investigates such phenomena is called solid granular material mechanics. The first part of this paper includes the qualitative explanation of the phenomenon, as well as some of the important reasons why we need to understand it well. The paper goes into the theoretical explanation of the observed physical effect. The effects of the cohesion, which begin to show up when working with finer materials, were also taken into account. In the experimental part of the paper the relevant parameters are divided into two main groups- the ones that affect the size of the angle of repose and the ones that affect the formation of the cone-like pile. All of these parameters, including the formation of avalanches are well examined and fully described. The method for taking measurements and the tools that were used are also described, as well as some additional factors, that can affect the measurements.
Keywords: angle of repose; granular material; conical pile; avalanche; cohesion; adhesion; moisture