Shear Behavior of Reinforced Concrete Beam with Partially Replaced Recycled Aggregate

The demolition of many concrete structures worldwide produces substantial waste, posing a significant environmental concern. Using this waste as recycled aggregate (RA) in fresh concrete can give a feasible solution to this problem. However, the inclusion of RA in concrete has challenges, especially in designing the shear capacity of beams. Therefore, this study investigates the effect of RA replacement percentage on the shear capacity of reinforced concrete beams. Three variations of RA replacement percentages (0, 30, and 50%) are considered to conduct the study. The shear capacity of the beams has been tested using a four-point loading test after 56 days of casting. According to the test result, the shear capacity of the beam improves for 30% replacement of RA by about 6–35%, which is significant. Further addition of RA causes a reduction of shear capacity. Replacing the natural aggregate with RA allows the beam to withstand more load against strain than the control concrete, indicating improved ductility in the beam. The maximum improvement in ductility is found with a 30% replacement of the RA.