Analytical Models and Guidelines for the Ductility Enhancement of Circular Reinforced Concrete Single-Column Bents Using Fiber-Reinforced Polymers

Abstract

The target displacement ductility requirements for circular RC single-column bridge bents are considered using a proposed multifailure mode algorithm to determine the required thickness of fiber-reinforced polymer wraps FRPs. The procedure is developed using two in-house computer algorithms, PACCC plastic analysis of circular concrete columns and PACCC-FRP, to generate a moment- curvature analysis using circular segment slices and subsequent failure mode predictions in single-column bents for both FRP-wrapped and unwrapped circular RC sections. The results of the study showed good comparison to published experimental tests at the ultimate force-deflection states of RC sections and against three commercial software test beds. The study uses PACCC-FRP to show that single columns experiencing a brittle failure may be retrofitted with FRP wraps in order to increase the displacement ductility and satisfy target ductility values within the ductility wrap envelope, or wrap-saturation level, as established herein. DOI: 10.1061/ASCEBE.1943-5592.0000136 CE Database subject headings: Brittle failures; Failure modes; Concrete columns; Column beams; Fiber reinforced polymer; Lateral displacement; Ductility. Author keywords: Brittle failure; Failure modes; Concrete columns; Fiber-reinforced polymers; Lateral displacement; Ductility.