An improved coupling of 3D state-based peridynamics with high-order 1D finite elements to reduce spurious effects at interfaces

Peridynamics (PD) is a nonlocal continuum theory capable of handling fracture mechanisms with ease. However, its use involves high computational costs. On the other hand, Carrera Unified Formulation (CUF) allows one to use one-dimensional high-order finite elements, resulting in excellent accuracy while improving computational efficiency. To address the high computational cost of solving fracture problems, a coupling technique between these two theories is necessary. Various approaches have been proposed to couple peridynamic grids with finite element meshes in the literature. However, most of these approaches are affected by arbitrary choices of blending functions and tuning parameters or exhibit spurious effects at the interfaces. To overcome these issues, we propose a simple coupling technique based on overlapping PD/CUF regions and continuity of the displacement field at the interfaces. This approach is verified through static analysis of classical beams and thin-walled structures with applications in the aerospace industry.