Fig. 1.

Schematic view of different configurations involved in the G&R response of a soft tissue. The original homeostatic configuration of the mixture κ(0) = κ_o is chosen as the reference configuration for the computation of G&R deformations of the mixture via F(τ), τ ∈ [0, s]. The deformation experienced, at time s, by the material element of constituent α deposited at time τ is given by ${\mathbf{F}}_{n(\tau )}^{\alpha }(\mathit{s})=\mathbf{F}(\mathit{s}){\mathbf{F}}^{-1}(\tau ){\mathbf{G}}^{\alpha }$, where we assume that the constituents are deposited with constant prestretches G^α (τ) = G^α and that all constituents are constrained to deform with the mixture.