  A nonlocal model of peridynamic type for dynamic brittle damage is introduced
consisting of two phases, one elastic and the other inelastic. Evolution from
the elastic to the inelastic phase depends on material strength. Existence and
uniqueness of the displacement-failure set pair follow from the initial value
problem. The displacement-failure pair satisfies energy balance. The length of
nonlocality $\epsilon$ is taken to be small relative to the domain in
$\mathbb{R}^d$, $d=2,3$. The new nonlocal model delivers a two point strain
evolution on a subset of $\mathbb{R}^d\times\mathbb{R}^d$. This evolution
provides an energy that interpolates between volume energy corresponding to
elastic behavior and surface energy corresponding to failure. In general the
deformation energy resulting in material failure over a region $R$ is given by
a $d-1$ dimensional integral that is uniformly bounded as $\epsilon\rightarrow
0$. For fixed $\epsilon$, the failure energy is nonzero for $d-1$ dimensional
regions $R$ associated with flat crack surfaces. This failure energy is the
Griffith fracture energy given by the energy release rate multiplied by area
for $d=3$ (or length for $d=2$). The nonlocal field theory is shown to recover
a solution of Naiver's equation outside a propagating flat traction free crack
in the limit of vanishing spatial nonlocality. Simulations illustrate fracture
evolution through generation of an internal traction free boundary as a wake
left behind a moving strain concentration. Crack paths are seen to follow a
maximal strain energy density criterion.
