A local strain-based implementation strategy for the extended peridynamic model with bond rotation

The conventional grid displacements-based implementation of the extended peridynamic model with bond rotation may give rise to some difficulty in predicting non-uniform deformation field, essentially due to the existence of local rigid rotation in solid. This paper presents a novel alternative local strain-based implementation technique for handling the numerical issue. The key is to formulate the relative displacement between particles in terms of the strain tensor approximated locally rather than the direct use of displacements at peridynamic particles. It is critically proved that bond stretch is independent of the rigid rotation tensor. Local strain is thus required only for approximating local shear deformation. The model is currently implemented for static problems in a hybrid manner and in a finite element/peridynamics coupling framework, the latter allowing direct and correct imposition of boundary conditions. To illustrate the performance of the proposed method in numerical accuracy and computational efficiency, various examples are performed with varying Poisson's ratio and comparisons with the results from finite element analysis are presented. (C) 2019 Elsevier B.V. All rights reserved.