Investigation of Crack Propagation Exercising DIC Technique in Partial Replacement of Fine Aggregate Using Recycled Materials

The research objectives of this paper are to investigate the influence of replacing sand with crumb rubber (CR) on the mechanical properties of concrete, specifically the compressive and flexural strength. Digital image correlation (DIC) is used as a novel approach to close-form (accurately) measure displacement and strain in CR concrete specimens. The DIC-derived data are then correlated with the experimentally determined mechanical properties to validate the effectiveness of DIC in assessing the CR concrete behavior. Specifically, this study uses DIC to assess deflection, strain, and the spread of structural damage. The DIC procedure is an evaluation approach that does not cause damage. Given how accurately cracks represent both the structural health of the entire system and the state of the concrete itself, they should be closely monitored for expansion. A high-motion digital camera and microscope are used to image the DIC samples. The generated displacement data display typical movement from the subimage center to analyze the starting point. Several images of the material are taken using image processing software, which then calculates the deformation at any location in the field and the rates of strain and fracture propagation. These results highlight the wide range of applications of the DIC approach, including evaluating cracks caused by shrinkage in freshly laid concrete and masonry structures. In this investigation, the interface is only partly bonded to stop the rupture from spreading to the ends of the specimen. To give the surface of the pictures distinguishing characteristics for image matching, a speckle pattern is applied. The models are photographed both before and after dynamic rupture using a camera. The acquired displacement data are converted to strains and stresses using nonlocal denoising procedures. CR is used to replace some of the fine aggregates. This work employs the DIC procedure to capture the transient phenomena connected with dynamic rupture. Using the DIC procedure and MATLAB software, the surface displacement and strain in concrete were measured.