Shear behavior of green concrete beams reinforced with basalt FRP bars and stirrups

Abstract

This study investigated the shear performance of large-scale green concrete (GC) beams reinforced with basalt fiber reinforced polymer (BFRP) bars and stirrups. The GC concept was employed in this study by partially substituting the cement content with 35% by weight of industrial by-products (fly ash and silica fume). The main test variables were the reinforcement ratio, the shear span to depth ratio (a/d), and the spacing between stirrups. Three beams were transversely reinforced with steel stirrups to serve as a control. Experimental results indicated that the ultimate shear capacity was significantly increased at higher reinforcement ratios. Such effect was less pronounced in beams with reduced spacing between stirrups. In addition, the BFRP stirrups were effective in reducing the diagonal shear crack width and increasing the ultimate shear capacities of the tested beams. On the other hand, beams with a higher a/d ratio have shown higher deflection and reduced ultimate shear capacity. Comparing the experimental results of the current study with the current design codes and guidelines provisions, the CSA-S806-12 has shown the best predictions with a mean experimental to predicted shear (Vexp/Vpre) ratio of 1.43 ± 0.29.