The performance of carbon fiber reinforced polymer (CFRP) strengthening systems is fundamentally dependent on the bond between the CFRP and the concrete substrate. In particular, when applied to shear strengthening of I-shaped cross sections, the bond is often inefficient due to the concave geometry of the cross section. This inefficiency typically leads to premature debonding at the web-flange corners, resulting in a limited increase in shear strength. This paper presents a small set of an extensive experimental study focusing on three shear strengthening configurations for I-sections using CFRP spike anchors or epoxy-bonded in-fill concrete blocks. The results indicate that CFRP spike anchors placed at the web-flange corners enhanced the performance of the shear strengthening system by up to 13%. Furthermore, when epoxy-bonded in-fill concrete blocks were combined with spike anchors in the compression zone, the shear strengthening system’s performance was improved by up to 23%. The latter configuration proved to be particularly effective, as it completely eliminated debonding around the web-flange corner. The final section provides a summary of the large-scale implementation of the optimal configuration among the three.