Bond-Based Peridynamics with Stretch and Rotation Kinematics for Opening and Shearing Modes of Fracture

This study presents a new bond-based peridynamic approach for modeling the elastic deformation of isotropic materials with bond stretch and rotation, thus removing the constraint on the Poisson’s ratio. The resulting PD equilibrium equations derived under the assumption of small deformation are solved by employing implicit techniques. The bond constants associated with stretch and rotation kinematic are directly related to the constitutive relations of stress and strain components in continuum mechanics. Also, the expressions for the critical stretch and critical relative rotation are derived in terms of mode I and mode II critical energy release rates, respectively. Lastly, it does not require a surface correction procedure, and the displacement and traction type boundary conditions are directly imposed without introducing fictitious regions in the domain. The capability of this approach is first demonstrated by capturing the correct deformation of plate type structures under general loading conditions. Subsequently, its capability for failure prediction is established by simulating the response of a double cantilever beam (DCB) under mode I type loading and compact shear specimen under mode II type loading.