The article presents a study of the stress-strain state of RC beams using Digital Image Correlation (DIC). DIC is also highly effective in studying reinforcement deformations, as reinforcement undergoes significant stresses during the service life of RC structures. Reinforcement typically operates in the tensile zone, where stresses and deformations may be uneven due to local defects or corrosion. DIC allows for an assessment of how deformations are distributed along the reinforcement bar and identifies zones of stress concentration. The method allowed for a detailed analysis of the strains distribution, identification of critical stress localization zones, crack formation, and tracking the process of neck formation in the reinforcement in real-time and under varying load levels. An evaluation of the effectiveness of restoring damaged concrete beams using the repair mortar Sika MonoTop-4012 and epoxy adhesive Sikadur-30 was carried out. The results showed that the restored RC beams exhibit increased crack resistance and restoration of load-bearing capacity to operational levels, proving to be effective restoration methods. The obtained data confirm the feasibility of using DIC for monitoring the load-bearing capacity of structural elements, studying their stress-strain state, and predicting their durability.