Dilatancy transition in a granular model

We introduce a model of granular matter and use a stress ensemble to analyze shearing. Monte Carlo simulation shows the model to exhibit a second order phase transition, associated with the onset of dilatancy.Comment: Future versions can be obtained from: http://www.ma.utexas.edu/users/radin/papers/shear2.pd

Molekulardynamik-Simulationen beliebig geformter Teilchen in zwei Dimensionen

In order to contribute to a better knowledge of shearing phenomena in granular media a computer model has been developed assuming particles of arbitrary polygonic shape. Statistical and dynamical algorithms are presented for the generation of Delannay and Voronoi lattices. In numerical shear cell experiments the dependency of dilatance and shear power on the shear velocity and the standard power was studied. The model describes even the well-known spontaneous formation of shear bands in the cells. The two- dimensional simulation of a shear zone between two tectonic plates yields earthquake statistics corresponding to the Gutenberg-Richter law. Additional application cases of the simulation model are demonstrated: granular flow through feeding hoppers, bulk materials in tumblers and crystallization phenomena. (WEN)Available from TIB Hannover: RA 831(3038) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman