Peridynamics-Based Digital Image Correlation Algorithm Suitable for Cracks and Other Discontinuities

AbstractThis work presents a novel approach to circumventing the difficulties associated with using digital image correlation (DIC) for problems that involve discontinuities like fracture and fragmentation. The proposed method provides a simple means to combine traditional DIC approaches with peridynamics to achieve full-field displacements, even in the vicinity of cracks. In regions where DIC is accurate and effective, the displacement field is determined using a traditional approach. In discontinuous regions, the displacement field is solved for using peridynamics. This study shows that this method can be used successfully for investigating damage in materials such as nuclear graphite and fiber-RC (FRC). It also shows that the proposed method alleviates nonphysical strains in the vicinity of cracks, common to alternative approaches, which detrimentally degrade the quality of postprocessed quantities of interest such as fracture toughness.

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