According to the building material promotion council (BMPTC) India generates 150 million tons of
construction and demolition waste per year. From this demolition waste, we can recycle the concrete aggregates
replacing natural coarse aggregate to make it more sustainable. This experimental research aims to study the rheological behavior of M50 and M60 grade concrete. The replacement of NCA with RCA in this study was 0%, 20%, 40%, and 60% along with the cement replacement of 25% by fly ash. The polycarbonate (PC) based superplasticizer was used for the concrete. The tests performed to study the rheology of concrete were slump test, Vee-Bee test, compaction factor test & flow table test. The mathematical equation is been formulated showing the interrelation between the results found in the above tests. The promising results will reduce the cost of concrete on-site significantly and the mathematical equation formulated will help for on-site calculations of the quantity of recycled concrete aggregate for the expected rheological behavior of concrete.