Summary: | 碩士 === 國立中央大學 === 土木工程研究所 === 94 === In this thesis, a new algorithm and a computer code are developed for 3D numerical simulations of granular assemblies composed of egg-shaped particles, ellipsoidal particles and long ellipsoidal particles. The newly developed egg-shaped particles are designed by the revolution of an ellipse, formed by four connected arcs, about the major axis passing through its centroid in order to speed up the process of algorithm. Coordinates of the centroid, directions of the major axis and lengths of major and minor axes are the essential data for the packing generation and associated contact detection.
The domain to be filled with particles can be a polyhedron of any shape. Simulation results can be processed by MATLAB 7.1 to display the distribution of particles in space and the fabric structure at any instant. Parameter studies of the influence of the void ration, the contact numbers among the gravels, particle shape and the internal friction angle between particles on the macroscopic behaviors of particles assemblies are conducted in this thesis. In this study, it emphasizes the relationship between the angle of repose and the particle shape. The reactions of angle of repose are taken account by the relative particle shape through remove one side of wall and set a wall spinning slowly into 90 degree. It is found that the particle shape will influence the angle of repose, ellipsoidal particles are the most, and then egg-shaped particles and the long ellipsoidal particles are the least.
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