This research investigates the mechanical behavior of reinforced concrete (RC) beams under cyclic shear loading, with a focus on evaluating the effectiveness of textile-reinforced mortar (TRM) composites as a retrofitting technique. The study aims to assess both local and global structural responses, particularly under repeated loading conditions. A total of six tests were performed, including monotonic loading to failure for both unstrengthened and TRM-retrofitted beams, as well as cyclic loading applied to two unretrofitted and two retrofitted RC specimens. To characterize the local strain distribution and damage evolution, distributed fibre optic sensing (DFOS) was integrated within the TRM layer, while digital image correlation (DIC) was employed to monitor surface crack development in the shear-critical regions. These methods enable a detailed evaluation of the TRM's contribution to shear resistance and its behavior under cyclic demands. Monotonic and cyclic test results show that TRM reinforcement increases beam stiffness and leads to distributed cracking, preventing a dominant diagonal crack. This led to over 75% reduction in crack openings, enhancing durability and serviceability. TRM also reduces the load on existing stirrups, especially in poorly reinforced zones. Its effectiveness depends on adequate load transfer length across cracks, without it the TRM load bearing capacity is not ensured.