This note deals with structured deformations introduced by Del Piero and
Owen. As treated in the present paper, a structured deformation is a pair
where
is
a macroscopic deformation giving the position of points of the body and
represents deformations without disarrangements. Here
is a map of bounded variation on the reference region
, and
is a Lebesgue-integrable tensor-valued map. For structured
deformations of this level of generality, an approximating sequence
of simple
deformations is constructed from the space of maps of special bounded variation on
, which converges
in the
sense to
and for which the sequence
of total variations of
is bounded. The condition is optimal. Further, in the second part of this note, the
limit relation of Del Piero and Owen is established on the above level of
generality. This relation allows one to reconstruct the disarrangement tensor
of the structured
deformation
from the information on the approximating sequence.
Keywords
structured deformation, fracture, approximations, maps of
bounded variation, maps of special bounded variation