Time-dependent deformations of concrete beams reinforced with CFRP bars

Carbon FRP is recently used as a reinforcing element in concrete structures in view of its excellent resistance to corrosion. The paper presents studi es of the long-term behavior of the beams reinforced with carbon-epoxy FRP under uniform sustained loading. Four rectangular concrete beams reinforced with CFRP bars were cast in two sizes; 152 mm x 203 mm x 2438 mm, and 152 mm x 152 mm x 2438 mm. The beams were simply supported and subjected to a u niform sustained loading. The beams were instrumented and monitored to obse rve the changes in the behavior due to creep and shrinkage of concrete. Obs ervations were recorded regularly for nearly two years. An analytical metho d is developed to predict the long-term behavior of CFRP internally reinfor ced concrete beams. The calculated deflections, strains and curvatures comp are reasonably with the experimental values. A simplified equation for calc ulating the long-term deflection is proposed for CFRP reinforced concrete b eams. (C) 2000 Elsevier Science Ltd. All rights reserved.