Splitting Bond Capacities of Concrete Element Reinforced with Continuous Fiber

This paper presents an experimental work and prediction of bond capacities of longitudinal steel rebar for concrete element with the polyacetal fiber (PAF) including internal reinforcements and externally wrapped sheets for confinement, where the bond capacity means an average bond resistance over a length of embedment of the rebar. The objectives of this study are to clarify bond behavior and to evaluate the bond strength. The loading tests were performed on 22 cantilever type specimens that vary on the amount and the location in a cross section, such as stirrup (peripheral around rebars), subtie, and jacketing. The test results indicated that the maximum bond capacity could improve with PAF as internal and external reinforcements consist of filaments and sheets, respectively. Considering strain behavior of transverse reinforcements, the writers proposed a new predictable equation for internal reinforcements. On the other hand, a predictable equation for the PAF sheets was also derived from the efficiency coefficient of PAF sheets on shear capacity of the RC element, which was already proposed. Both the bond strengths of average and each rebar were predicted by respective proposed equations. The close approximations were obtained to experimental data for internal and external fiber reinforcements.