Behavior of Shear-Critical Recycled Aggregate Concrete Beams Containing BFRP Reinforcement

The shear performance of recycled aggregates beams reinforced with basalt fiber-reinforced polymer (BFRP) bars is evaluated and compared with that of similar beams made with natural aggregates (NA). Six beams with a shear span-to-effective depth ratio (a/d) of 3.0 were tested to failure. Test variables consisted of the recycled concrete aggregate (RCA) replacement percentage (60 and 100%) and the presence of BFRP stirrups in the shear span. Experimental results showed that a RCA replacement of 60% marginally reduced (5%) the shear capacity. However, the reduction in the shear capacity was more pronounced (17%) for the specimen made with 100% RCA. The contribution of BFRP stirrups to the shear capacity decreased with an increase in the RCA replacement percentage. The width of the major shear crack at a given value of load was higher for the beams with RCA. The deflection values at the ultimate load were greater for beams made with RCA. A codified analytical approach as well as a model published in the literature were employed to predict the shear capacity of the tested beams. Predictions of the codified analytical approach were very conservative. The analytical model published in the literature provided a more reasonable prediction for the shear capacity of the tested beams than that of the codified analytical approach.