  It is well known that classical constitutive models fail to capture the
post-peak material behaviour, due to localisation of deformation. In such cases
the concept of Representative Volume Element (RVE) on which classical continuum
models rest ceases to exist and hence the smearing out of local inhomogeneities
over the whole RVE is no longer correct. This paper presents a new approach to
capturing localised failure in quasi-brittle materials, focusing on the
kinematic enrichment of the constitutive model to describe correctly the
behaviour of a volume element with an embedded localisation band. The resulting
models possess an intrinsic length scale which in this case is the width of the
embedded localisation band. The behaviour therefore scales with both the width
of the localisation band and the size of the volume on which the model is
defined. As a consequence, size effects are automatically captured in addition
to the model capability in capturing behaviour at the scale of the localisation
zone.
