Structural Performance of Reinforced Concrete Beams Retrofitted Using Modularized Steel Plates in Precast Concrete with Bolted Connections

The previous research introduced an innovative retrofitting technique for reinforced concrete beams using modularized steel plates. This technique enhances structural performance, offering a lightweight solution compared to conventional retrofitting methods using steel plates, and accommodates construction errors. However, a challenge arises due to the lack of integrity between unit steel plates. To address this, this study proposes a novel method of connecting each steel plate with bolts. The experimental results show that retrofitted beams achieved a maximum load of 311.9 kN, roughly 1.6 times that of non-retrofitted specimens, with the ductility of retrofitted beams being 3.3 times that of the non-retrofitted beams. Additionally, there was a 25% increase in load capacity for beams retrofitted with interconnected steel plates compared to those without connections between unit steel plates.