Partially hydrated recycled aggregate concrete: A systematic approach towards sustainable development

The experimental investigation on the mechanical properties of partially hydrated recycled aggregate concrete (PHRAC) with the addition of polypropylene fiber (PP fiber) is carried out and compared with the conventional concrete. The 28 days compressive strength is observed to be higher for PHRAC, whereas the tensile strength is lower than natural aggregate concrete (NAC). Based on the mechanical properties, the optimal dosage of PP fiber for both NAC and PHRAC is obtained as 0.6% by weight of cement. The bond strength is also evaluated by conducting the pullout tests using rebar of 12 mm, 16 mm and 20 mm diameter. Higher bond strength is experienced for PHRAC with respect to NAC, whereas the PP fiber addition does not have a significant effect on the bond strength of concrete. Further, t-test reveals that, barring flexural tensile strength other mechanical parameters are not influenced either by the type of aggregate or by the incorporation of PP fiber. The cost analysis shows that, the preparation of PHRAC is 4.5% cheaper than NAC.