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The dual‐function retrofitting system that uses the carbon‐fabric reinforced cementitious matrix (C‐FRCM) as both the anode of impressed current cathodic protection (ICCP) system and the structural strengthening (SS) material, that is, an ICCP‐SS system, is investigated. The experimental program mainly focused on the shear behavior of C‐FRCM strengthened reinforced concrete (RC) continuous beam under the dual‐function retrofitting system. The influence of anode polarization on the shear strengthening of RC continuous beams is analyzed. Shear tests were conducted on a total of 14 corroded RC continuous beams to investigate the influence of key parameters, including anode polarization degree of prefabricated C‐FRCM plate, layer of carbon fiber mesh and side‐wrapping. The failure modes, shear capacities, and load‐deflection curves of the shear‐strengthened RC continuous beams are reported. Based on the test results, the applicability of relevant design codes was evaluated and found to provide rather conservative predictions for the shear capacity of the examined C‐FRCM strengthened RC continuous beams. [ABSTRACT FROM AUTHOR]

This article presents the results of an experimental parametric study on reinforced concrete (RC) beams strengthened by an external bonding of carbon fiber reinforced polymer (CFRP) laminates to their tensile faces. This experimental work investigates the effects of both CFRP laminate sizes and concrete compressive strength on the flexural behavior of strengthened RC beams. Accordingly, a total of 10 RC beams have been cast, eight of which were strengthened in flexure by external bonding of CFRP laminate by varying its sizes, such as length, width, and thickness, and two control beams. All prepared beams were tested under standard four‐point bending until failure. The load–deflection response curves and failure modes were recorded and compared. Results show that failure modes of strengthened beams varied with the CFRP laminate characteristics from steel yielding, CFRP peeling off, and interfacial debonding laminate, Also, the load–deflection curves showed a considerable increase in the load capacity by up to 1% and 112%, compared to the unstrengthen beam, if the CFRP laminate length ratio passes from 0.40 to 0.94, respectively. In addition, the load capacity contribution increases from 56% to 112% when the CFRP laminate width increases from 50 to 100 mm. On the other hand, when laminate thickness increases from 1.2 to 2.4 mm, the load capacity contribution increases from 56% to 76%. Finally, it is concluded that the mechanical behavior of strengthened beam is strongly affected by the CFRP laminate sizes. [ABSTRACT FROM AUTHOR]

This paper investigates the influence of cyclic preloading on the fatigue behavior of reinforced concrete (RC) beams rehabilitated with near surface mounted (NSM) carbon fiber reinforced polymer (CFRP) reinforcement. The study includes eight RC beams with dimensions of 152.4 × 152.4 × 1,521 mm. Strengthened and nonstrengthened specimens were tested under monotonic loading to obtain the flexural static capacity. Two strengthened specimens were tested as a reference under constant amplitude cyclic stress without prefatiguing. Four nonrehabilitated RC beams were prefatigued to simulate service loading conditions. Later, these RC beams were rehabilitated with NSM CFRP reinforcement and tested under the same cyclic stress range of the reference specimens. Mid‐span deflection, strain of tension steel rebars and CFRP rods, stiffness degradation, and energy dissipation were analyzed and evaluated. Experimental results show that the rehabilitated prefatigued RC beams had similar stiffness degradation and failure modes to the reference strengthened RC beams. The rehabilitated RC beams had an improvement in the fatigue responses when compared to the reference strengthened RC beams. Moreover, the postfatigue monotonic behavior of the rehabilitated RC beams showed an increase in the elastic modulus and a decrease in ductility. [ABSTRACT FROM AUTHOR]