Experimental and numerical analysis of the collapse of a granular column in water at rest

Collapsing of a granular column is a case study often used to observe granular media. The goal of this master thesis is to contribute to granular media modelling research by designing a granular column collapse experiment. The purpose of this experiment is to obtain usable video recordings of collapsing sand columns in water at rest. Based on the recordings, an analysis and a comparison with the model of Monsorno et al.is performed. This paper is set out to explore the design of the experiment, including its limits and boundaries. First, a review of the existing literature is realized : this allows to place the relevance of this document in its context. An other chapter of this document elaborates on a summary of the main parameters which may have an influence on the collapse of a granular column. Regarding the experiment, a parametric analysis of the initial aspect ratio, grain size and volume fraction is provided. Finally, results are compared with simulations based on the model of Monsorno et al..Experiments and videos are realised in the laboratory in the LEMSC at UCLouvain with a high-speed camera. Two sort of sand, four different aspect ratios and two sort of initial volume fractions are used. The water-free surface and sand deposit are analysed by the means of a Matlab procedure. The velocities of the granular flows at various timings are analysed through ParticleImage Velocimetry (PIV) via the softwareDaVis 8(LaVision).This work allows to highlight the differences between a theoretical model and experimental results. It provides a panel of videos allowing researchers to compare their results with laboratory experiments. Finally, this work treats on the possibility of usingPIV analysis to observe granular media.