Impact of CFRP-strengthening on Crack Formation in RC Structures

Abstract This study investigates the impact of carbon fibre-reinforced polymer (CFRP) strengthening on the crack formation and propagation in reinforced concrete (RC) beams through a combination of experimental and theoretical approaches. Unstrengthened and CFRP-strengthened full-scale RC beams were tested under bending loads to evaluate their crack resistance and structural performance. A Digital Image Correlation (DIC) approach was employed for detailed, full-scale monitoring of crack propagation, enabling precise tracking of strain distribution and crack growth throughout the loading process. The results demonstrated that CFRP significantly delays the initiation of cracks, reduces crack widths, and enhances the load-bearing capacity of RC beams. Crack behaviour observed in the experiments closely aligns with theoretical predictions, confirming the applicability of existing standards for the design and analysis of CFRP-strengthened structures. Moreover, the DIC system provided invaluable insights into crack dynamics, highlighting the potential of advanced optical techniques in structural diagnostics. The findings contribute to closing the knowledge gap in CFRP reinforcement applications, paving the way for more resilient and efficient infrastructure solutions.