Replacement of Fine Aggregates by Recycled Construction and Demolition Waste in Pavement Quality Concrete

Abstract

Reusing of Construction and Demolition (C and D) waste is one among the numerous pathways that provide a wide convenience to avert waste materials from infiltrating the landfills and reduces the construction industry reliability on depleting natural resource supplies. Reinstating of fine aggregates in a concrete is studied with five incremental ratios such as 20, 40, 60, 80, and 100%. Since debris are coated with fine cementitious particles, the water absorption potential will be high. Hence, the beneficiation process is carried out by acid treatment process. After beneficiation, the water absorption capacity got reduced by 63%, soundness value improved by 29% and specific gravity increased by 13%. The aided aggregates were replaced for fine aggregates in M30 and M40 grade concrete. Results show construction and demolition waste as a possible natural aggregate replacement material with nominal changes in their physical characteristics. The changes in the strength properties were compared to control mix. From the study, it is found that an effective replacement of 31.97 and 20.05% of Recycled Fine Aggregate for M30 and M40 grade, respectively. The compressive strength is found to be for M30—37.29 and M40—48.06 N/mm2, the flexural strength is found to be for M30—10.22 and M40—13.36 N/mm2 and the fatigue strength for M30—372,356, 89,562, 48,249, 23,732 and 4955 no. of cycles and M40—873,925, 128,890, 73,664, 32,976, and 7112 no. of cycles for stress ratio 0.55, 0.60, 0.65, 0.70, and 0.75, respectively.