Reliable Estimation of Permeability from the 4D Strain Distribution in Poroelastic Tissues

The response of a poroelastic materials to a sustained applied unidirectional deformation is a volumetric strain propagating inside the tissue with a speed that is characteristic of the capacity of the fluid to diffuse through the elastic porous structure and the size of the sample. In the current work we investigated the role of the indenter size to measure a time of relaxation of the volumetric strain which relates only on the materials porous properties, without any influence of the size. The simulation showed that an indenter as big as 25% of the sample size can be an indenter small enough to provide reliable quantitative estimation. Experimental result, even if promising, do not permit to conclude on a definitive indenter size to obtain a similar result.