PORO-MECHANICAL COUPLING STRATEGIES FOR LARGE STRAIN COMPRESSION OF SOFT BIOLOGICAL TISSUES

Resumo

Early studies related to current poroelasticity theories are oriented towards problems in geomechanics.
In addition to their use in soil mechanics, biphasic theories play an important role in the field of biological soft
tissue mechanics. In this context, the elucidation of how mechanical stimuli are able to modify the behavior of

cells within the tissue makes computational mechanics and mechanobiology extremely relevant fields. In gen-
eral, due to the highly nonlinear coupled response coming from the biomechanical nature of the problem, large

time-dependent deformations, damage, and fluid-structure interaction are complex behaviors that usually lead to

difficulties in numerical solutions. Different types of schemes arise as an option to solve the mechanical equilib-
rium and mass conservation equations. Iteratively coupled methods emerge as an alternative to solve the biphasic

problem. Therefore, in this paper, we propose a numerical investigation of the so-called undrained scheme applied
to the finite element method using the updated Lagrangian approach. An unconfined case study is used to compare
the response of the iteratively coupled method with the monolithic scheme, where the governing equations are
solved simultaneously. In addition, the influence of an exponential permeability model on the volumetric strain
and pore pressure fields is assessed.