title: Gravitational compression of colloidal gels.
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, φ, inside the gel. We find φ 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 φ-dependence of the gravitational, elastic and viscous stresses acting on the gel.
authors.affiliation: Department of Physics and HSEAS, Harvard University, Pierce Hall, 29 Oxford Street, Cambridge, MA 02138, USA.
authors.forename: J J
authors.initials: JJ
authors.lastname: Liétor-Santos
authors.forename: C
authors.initials: C
authors.lastname: Kim
authors.forename: P J
authors.initials: PJ
authors.lastname: Lu
authors.forename: A
authors.initials: A
authors.lastname: Fernández-Nieves
authors.forename: D A
authors.initials: DA
authors.lastname: Weitz