  Backus (1962) developed his technique for homogenization of a layered
structure solely within the context of linear elastic theory. In this paper we
propose an extended use of Backus average for finitely deformed materials of a
layered structure. We attempt to use two different approaches to account for
large deformations. The first approach utilizes the connections between linear
and nonlinear transverse elasticity. For the second approach we use a
formulation based on prestress in the material. We conclude that the first
approach, although with some limitations, can be used successfully.
