Shear Behavior of Beams with Recycled Coarse Aggregates Having Rectangular Spiral Reinforcement

This study encompasses an experimental investigation of twenty beams carried out to investigate the effect of replacing natural coarse aggregate by recycled coarse aggregate in various amounts by weight. Ten beams were shear-reinforced with conventional (i.e., closed) stirrups, while another ten were transversely reinforced using rectangular inclined spiral reinforcement. All beams were subjected to an incremental static loading up to failure, where crack propagations, ultimate deflections, ultimate load values, and failure mechanisms were recorded and examined. Test results revealed that while all beams predominantly failed in shear, those with conventional stirrups exhibited similar behavior to those reinforced with rectangular spiral reinforcement for 25-50% replacement ratios. When higher replacement ratios were used (i.e., 75% and 100%), there was a noticeable deterioration in the ultimate measured shear force for the beams containing spiral reinforcement when compared to those with vertical stirrups.