COUNTERINTUITIVE PHYSICAL BEHAVIORS IN COUPLED CONSOLIDATION PROBLEMS

Resumo

The coupled nature of the equations composing Biot’s consolidation model often produces
quite unexpected behaviors. The most common one is the Mandel-Cryer effect, which refers to a pressure
increase in certain regions of the domain for a short period of time with no apparent reason. Although this
effect is well known and widely reported in the literature, a clear and comprehensive explanation on the
physical mechanism that causes of the Mandel-Cryer effect is not easily found. Another counterintuitive
behavior is observed in a fully saturated poroelastic column under the influence of a gravitational field.
In this case, the poroelastic properties can produce displacement profiles that defies the common sense.
In this paper, we provide a deep discussion on these phenomena and a few hypotheses for explaining
them are proposed. For instance, we argue that there must be a mechanism responsible for transferring
volumetric strain to different regions of the domain in order to occur the Mandel-Cryer effect. For the
poroelastic column, we propose a spring-mass system to explain the displacement profiles obtained in
different situations. All of these hypotheses are carefully tested through numerical experiments.