An Experimental Investigation on Recycled Aggregate Fiber Reinforced Concrete

This present investigation focuses on the effect of recycled coarse aggregate and steel fibers on the fresh and hardened properties of concrete containing recycled coarse aggregate as replacement for natural aggregate in M35 grade concrete. Natural aggregate was replaced by recycled aggregate in the proportion 10%, 20%, 30%, 40% and 50% replacement with optimum dosage of 6% steel fibers. The maximum size of recycled aggregate and natural aggregate was kept 20 mm and down size. In all mixes prepared, water/cement ratio was kept constant at 0.45 and super plasticizer was used at 0.75% by weight of cement to maintain workability of concrete. Cubes of size 100x100x100 mm, cylinders of size 100 mm diameter and 200 mm height and beams of size 100x100x500 mm were casted. The compressive strengths were evaluated at 7 and 28 days to know the performance in later age. Split tensile strength test were evaluated at 7 and 28 days to know the flexural and tensile behavior at 28 days. The values of density are also evaluated for respective strength parameters.