Flexural Behavior of Concrete Beams Strengthened with Near-Surface-Mounted CFRP Strips.
Flexural strengthening using near-surface mounted (NSM) fiberreinforced polymer (FRP) materials is a promising technology. As NSM reinforcement, the FRP is surrounded by concrete on three sides so the bond and damage problems associated with externally bonded FRP strengthening systems are reduced or eliminated. This paper presents experimental results from 12 full-scale concrete beams strengthened with NSM carbon FRP (CFRP) strips. Three companion unstrengthened specimens were also tested to serve as a control. Experimental variables include three different ratios of steel reinforcement ρs and two different ratios of CFRP reinforcement ρfrp. Yield and ultimate strengths, flexural failure modes, and ductility are discussed based on measured load, deflection, and strain data. Test results show measurable increases in yield and ultimate strengths; predictable nominal strengths and failure modes; and effective force transfer between the CFRP, epoxy grout, and surrounding concrete. Also, strengthening with CFRP resulted in a decrease in both energy ductility and deflection ductility.
|Main Author:||Yost, Joseph Robert.|
|Other Authors:||Gross, Shawn P., Dinehart, David W., Mildenberg, Jason J.|