Ridha MS
More than a decade of studies have shown the benefits of ultra-high performance concrete (UHPC) on a ductility, energy absorption, crack distribution, damage tolerance, and deformation capacity. Nevertheless, little information is available on the behavior of UHPC columns especially when confined with fiber-reinforced polymers (FRP). This paper presents the results of experimental program and analytical modelling for performance evaluation of square FRP tubular columns in filled with UHPC under axial-flexural (P-M) loading. Eight steel–reinforced UHPC specimens were tested. Four had FRP tubes and subjected to initial load eccentricity 0, 10, 85 and 95 mm. Three reference columns without FRP tube and subjected to initial load eccentricities 0, 10, 85 mm. The last one had FRP tube and subjected to pure bending. P-M interaction diagram of FRP tubular columns in filled with UHPC were drawn using the obtained experimental results and compared against theoretical P-M interaction diagram that based on the principles of ACI building code. Good agreement between experimental and theoretical results was observed with COV 5.9%.