1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 1 Axial Load-Bending Moment Diagrams of Carbon-FRP Wrapped Hollow Core Reinforced Concrete Columns Veysel Yazici 1 , Muhammad N.S. Hadi 2 Abstract: Hollow core reinforced concrete columns are generally preferred in use to decrease the cost and weight/stiffnesss ratio of members such as bridge columns and piles. With a simplified stress state assumption, strengthening a hollow core reinforced concrete column with FRP wrapping provides a biaxial confinement to the concrete which leads to a need of defining the effect of FRP wrapping on the strength and ductility of the hollow core reinforced concrete columns. In this study, two groups of four hollow core reinforced concrete columns (205 mm outer diameter, 56 mm hollow core diameter, and 925 mm height) were tested under concentric, eccentric (25 mm and 50 mm eccentricity) and bending loads to observe the effect of Carbon- FRP (CFRP) wrapping. All the columns had internal steel reinforcement. Half of the columns had three layers of circumferential CFRP wrapping, whereas the other half had no external confinement. Axial load-bending moment (P-M) diagrams of each group were drawn using the obtained experimental results for both groups. It was observed that, CFRP wrapped columns had higher load and moment carrying capacities than the other group. An analytical model is proposed for drawing the P-M diagram of CFRP wrapped hollow core reinforced concrete columns. CE Database subject headings: FRP; Column strengthening; Hollow sections; Eccentric Loads; Axial load-Bending moment diagram 1 Phd Candidate, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong NSW 2522 Australia. E-mail: vy210@uow.edu.au 2 Associate Professor in Structural Engineering, School of Civil, Mining and Environmental Engineering, University of Wollongong, Wollongong NSW 2522 Australia (corresponding author). E-mail: mhadi@uow.edu.au Manuscript Click here to download Manuscript: paper_asce_hadi.doc