Eur. Phys. J. E (2009) 28: 159-164
https://doi.org/10.1140/epje/i2008-10390-7

Regular Article

Gravitational compression of colloidal gels

Department of Physics and HSEAS, Harvard University, Pierce Hall, 29 Oxford street, 02138, Cambridge, MA, USA

^* e-mail: alberto.fernandez@physics.gatech.edu

Received: 13 May 2008
Revised: 10 September 2008
Published online: 18 November 2008

Abstract

We study the compression of depletion gels under the influence of a gravitational stress by monitoring the time evolution of the gel interface and the local volume fraction, , inside the gel. We find is not constant throughout the gel. Instead, there is a volume fraction gradient that develops and grows along the gel height as the compression process proceeds. Our results are correctly described by a non-linear poroelastic model that explicitly incorporates the -dependence of the gravitational, elastic and viscous stresses acting on the gel.