Ultimate State of Samples of Ellipsoids under Different Stress Paths
Publication: Journal of Engineering Mechanics
Volume 134, Issue 9
Abstract
The ultimate state of granular material was investigated by the discrete element method. This paper discusses a series of numerical triaxial tests on samples of two kinds of ellipsoids. Samples of three different densities were loaded along various stress paths. The ellipsoids were mixed in the proportions 50:50 by weight. The longer particles have an aspect ratio (major length/minor length) of 1.5 and the other particles have an aspect ratio of 1.2. The samples were generated by deposition under gravity to simulate the air-pluviation sample preparation technique. Then they were consolidated isotropically. Fourteen stress-path controlled triaxial tests were conducted numerically for each sample. They are sheared to the ultimate state to determine the friction angle and void ratio at the ultimate state. When samples of different densities were sheared along the same loading path, a unique ultimate state was observed. The initial density does not affect the ultimate state. However, when different loading paths are applied to the same numerical specimen, they do not always arrive at the same critical state in the void-mean stress space.
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Information & Authors
Information
Published In
Journal of Engineering Mechanics
Volume 134 • Issue 9 • September 2008
Pages: 723 - 729
Copyright
© 2008 ASCE.
History
Received: Apr 11, 2006
Accepted: Feb 20, 2008
Published online: Sep 1, 2008
Published in print: Sep 2008
Notes
Note. Associate Editor: Ching S. Chang
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