Investigation of the Behavior of Corroded and Noncorroded Steel Bars with Mechanical Splices in Reinforced Concrete Structures

Mechanical splices enable continuity of reinforcement, yet their behavior under corrosion remains a concern. We experimentally compare spliced (threaded couplers) and unspliced bars in corroded and noncorroded conditions across common diameters (16–22 mm). An accelerated corrosion protocol was applied, followed by tensile testing and metallographic examination. Under uncorroded conditions, yield strength differences between spliced and unspliced bars were small ( + 0.29 % – 0.95 % ). Under corrosion, losses in mechanical performance were more pronounced, and fracture location could shift relative to the coupler. An American Concrete Institute (ACI) 318 acceptance screen ( 1.25 F y ) indicated that only selected noncorroded spliced specimens (e.g., M18ST and M20ST) met the minimum requirement, while corroded spliced specimens generally did not. These results clarify when mechanical splices should be avoided in zones with high corrosion risk or ductility demand and motivate protective detailing in aggressive environments.