Experimental Study and Numerical Modeling of Cyclic Bond–Slip Behavior of Basalt FRP Bars in Concrete

Abstract

This study aims to explore the cyclic bond–slip behavior of basalt fiber-reinforced polymers (BFRP) bars. Experimental pullout tests under monotonic and cyclic loading patterns were conducted in order to examine the effect of the cyclic loading on the bond behavior of BFRP bars. The effects of cyclic loading characteristics, concrete compressive strength, and bar diameter on the bond–slip relationship were examined. In addition, the bond performance of bars with four different surface profiles (smooth, sand-coated, wrapped, and wounded) under different loading protocols was studied and compared to that of deformed steel bars. The results revealed that cyclic loading had a significant effect on the bond performance of BFRP bars and the bond–slip relationship was greatly dependent on the bar surface treatment, as well as the characteristics of the applied cyclic loading protocol. Also, cyclic loading magnified the effect of concrete compressive strength on the bond behavior. A numerical model was proposed to predict the bond–slip relationship of wounded BFRP bars under cyclic loading. The model predictions showed good agreement with experimental results.