Title: Digital image correlation cum generalised strain field equations approach for mixed mode SIFs
Authors: Naresh K. Raghuwanshi; Nipun Singh
Addresses: Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur, Rajasthan, 302017, India ' Department of Mechanical Engineering, Malaviya National Institute of Technology, Jaipur, Rajasthan, 302017, India
Abstract: The stress intensity factor (SIF) is a very important parameter in fracture mechanics. For complex geometries and mixed-mode loading cases, the mixed-mode SIFs evaluation is very difficult using the analytical method or strain gauge experiment. Further, the digital image correlation (DIC) technique with a basic standard SIF equation may not evaluate accurate values of SIFs. In this research paper, a hybrid method is proposed to evaluate mixed mode SIFs (mode-I and mode-II SIFs) by using generalised strain field equations near the crack tip of the specimen and DIC experimental method. First, the optimum radial location for the strain measurement near the crack tip is investigated using the DIC method. Based on the optimum radial location, a zone is decided for strain field measurements. After that, the strain is measured at different locations and directions using the DIC method. Subsequently, SIFs are evaluated by combining the strain field equations and measured strain data from the DIC method. The obtained results are compared with the finite element method (FEM) and found a good agreement between the proposed method and the FEM.
Keywords: DIC; digital image correlation; SIF; stress intensity factor; crack; strain measurement; radial location.
DOI: 10.1504/IJSISE.2024.142336
International Journal of Signal and Imaging Systems Engineering, 2024 Vol.13 No.2, pp.84 - 94
Received: 27 Jan 2024
Accepted: 21 May 2024
Published online: 23 Oct 2024 *