Non-contact strain measurement of loading-unloading splitting test on concrete

The exact modelling of reinforced concrete structures necessitates a thorough control of post-cracking behaviour and the evolution of plastic deformations of concrete during loading-unloading cycles. Conducting a direct tensile test is more complex than the other tests, like the splitting test. This study investigates using the splitting test with digital image correlation (DIC) technique to analyse concrete deformation. By filming and processing images of splitting cylindrical specimens using GOM Correlate software, full stress-strain curves up to failure are obtained. Strain gauges are also employed for comparison. Results are validated against an analytical model, showing good agreement between stress-strain curves from both methods. The study concludes that DIC offers several advantages over conventional methods, including enhanced post-peak data acquisition and the ability to monitor cracks individually, regardless of their location on the surface. This approach improves the understanding of post-cracking behaviour and the evolution of plastic deformation in concrete structures.