Planar column collapse of elongated grains

The granular column collapse is a benchmark configuration for the study of granular flows in dry, saturated, and submerged conditions. The collapse sequence and resultant mobility is acknowledged to be controlled by the column aspect ratio, while grain properties define the relative transition of each stage. Grain shape effects are found to modify the global shear resistance of granular media, with a strong and coupled interaction when interacting with a fluid. In this work, we present the first steps towards the study of grain shape effects in a column collapse when interacting with an ambient fluid. For this purpose, we use a planar configuration and explore the collapse of a column consisting of rod-like grains and study the initial and after collapse grain orientations. On it, the mobilized grains deposit in a preferential horizontal orientation, but further experiments are required to confirm if a nematic configuration can be achieved.