  In this paper we present a novel formulation for phenomenological anisotropic
finite visco-hyperelasticity. The formulation is based on a multiplicative
decomposition of the equilibrated deformation gradient into nonequilibrated
elastic and viscous contributions. The proposal in this paper is a
decomposition reversed respect to that from Sidoroff allowing for anisotropic
viscous contributions. Independent anisotropic stored energies are employed for
equilibrated and non-equilibrated parts. The formulation uses logarithmic
strain measures in order to be teamed with spline-based hyperelasticity. Some
examples compare the results with formulations that use the Sidoroff
decomposition and also show the enhanced capabilities of the present model.
