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ABSTRACT A recently developed Timoshenko‐based peridynamic model with a variable micropolar shear influence factor is extended to study the behavior of dynamic crack propagation in functionally graded materials (FGMs). To this end, first, the proposed model is validated against two experimental three‐point bending benchmark problems with different material functions as well as varying loading rates and durations. Then, numerous additional cases with different boundary conditions and material distribution are studied to predict crack initiation and propagation in such mediums. The examples consist of three‐point bending and Kalthoff–Winkler specimens with various material functions under dynamic loads. Finally, the effects of material anisotropy induced by functionally varying material properties on crack propagation path are addressed. It is shown that this new model is advantageous because of its capability to account for shear deformation effects in the bonds previously ignored by the original bond‐based peridynamic models. Moreover, comparing the proposed modified bond‐based model to more complex methods, such as state‐based peridynamics, reveals that the simplicity of the current approach results in lower computational costs while still achieving comparable results.
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This content will become publicly available on January 24, 2026
Mixed-mode dynamic crack propagation analysis in anisotropic functionally varying microcellular structures
For the first time, the mixed-mode dynamic fracture in anisotropic functionally varying microcellular structures is investigated herein. To this end, a recently developed homogenization MATLAB implementation capable of considering material and geometry-induced anisotropy is used, and a continuous medium with equivalent functionality distributed mechanical properties to the original microcellular domain is obtained. Then, the resulting material domain is subjected to dynamic loads, and the crack propagation is predicted by using a novel Timoshenko-based peridynamic model. This innovative method unprecedentedly accounts for a bond-length dependent shear influence factor and a shear strain-based failure criterion. Finally, numerous cases consisting of compact-tension (CT) and Kalthoff-Winkler specimens with several void sizes, shapes, and distribution patterns are numerically solved. The results demonstrate that the crack path is significantly influenced by the void distribution pattern near the crack tip, providing a foundation for engineering crack propagation to prevent it from reaching critical areas of a structure.
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- Award ID(s):
- 2317406
- PAR ID:
- 10568042
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Results in Engineering
- ISSN:
- 2590-1230
- Page Range / eLocation ID:
- 104117
- Subject(s) / Keyword(s):
- microcellular materials material homogenization functionally graded materials anisotropic dynamic brittle fracture computational fracture mechanics Timoshenko-based peridynamics
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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