Stewart A. Silling, David J. Littlewood and Pablo
Seleson
Vol. 10 (2015), No. 5, 591–612
DOI: 10.2140/jomms.2015.10.591
Abstract
A notion of material homogeneity is proposed for peridynamic bodies with variable
horizon but constant bulk properties. A relation is derived that scales the force state
according to the position-dependent horizon while keeping the bulk properties
unchanged. Using this scaling relation, if the horizon depends on position, artifacts
called ghost forces may arise in a body under a homogeneous deformation. These
artifacts depend on the second derivative of the horizon and can be reduced by
employing a modified equilibrium equation using a new quantity called the
partialstress. Bodies with piecewise constant horizon can be modeled without ghost
forces by using a simpler technique called a
splice. As a limiting case of
zero horizon, both the partial stress and splice techniques can be used to
achieve local–nonlocal coupling. Computational examples, including dynamic
fracture in a one-dimensional model with local–nonlocal coupling, illustrate the
methods.