23 Mar 2026

Experimental Evaluation of Corroded Steel Beams Retrofitted with Fiber-Reinforced Polymers

Abstract: Corrosion represents one of the main threats to steel structures working in harsh conditions. It compromises the safety and integrity of marine structures, reducing their lifespan and increasing their maintenance cost. Recent studies investigated the use of fiber-reinforced polymers to repair corroded steel structures; however, these studies showed unmatured debonding behavior, stopping short of examining the impact of these repairs on the ductility of different steel elements. In this study, we conduct a series of full-scale experimental tests to investigate the impact of chemical corrosion on steel beams as well as the impact of repairing the beams using carbon fiber–reinforced polymer (CFRP) and basalt fiber–reinforced polymer (BFRP) in enhancing the beams’ structural performance. Corrosion, introduced to the beams’ tension flange and web elements, is used to establish a baseline dataset that captures the impact of repairs on corroded steel surfaces. The results show that the reduction of the flange and web section lowers the beams’ yielding load by 10% and 1%, respectively, compared with a beam with a full cross section. CFRP and BFRP patches can partially restore the corroded beams’ ductility; however, the fracture of the CFRP patches reduces the beam strength by 31% compared with its ultimate strength.