Seminar - Colin Thornton - DEM Simulation of Quasi Static Behaviour of Granular Materials

Colin Thornton
University of Birmingham


Friday 6 March 2008, 1.10 - 1.55 pm
Civil Engineering Lecture Theatre 3

Abstract:

The vast majority of current experimental research in soil mechanics is focused on axisymmetric compression tests. Even though plane strain deformation is a close approximation to many geotechnical engineering problems there is very little work devoted to examining the plane strain response of granular media. Although the general case in geotechnical engineering problems is one in which s1 .NE. s2 .NE. s3 there is probably less than ten research groups worldwide that have facilities for "true triaxial testing". Although the tradition is that theory is tested by experiment it is not clear whether such complex "true" triaxial apparatuses provide entirely reliable results. An alternative is to numerically simulate complex loading paths in general 3D stress space.

The presentation will show results of 3D Discrete Element Method (DEM) simulations in which radial deviatoric straining is applied and the corresponding stress response envelopes are shown to correspond to Lade surfaces. Further examination of the data reveals the corresponding flow rule and scaling law.