Rapid growth in construction has resulted in usage of large quantity of natural resources leading to the degradation of environment. Also, the demolition waste is on the rise year by year due to ending of service of the building and modifications to meet latest requirements. Adoption of technology for recycling the construction and demolition (C and D) waste provides a better way of resolving this issue and it will lead to environmental sustainability. Recycled Concrete Aggregate (RCA) is one such environment‐friendly material. RCA usually possess greater porosity and lower density and strength when compared to natural aggregate. Most of the experiments proved that the reduction in the strength of recycled aggregate concrete (RAC) is not appreciable up to 40% replacement of natural aggregate with RCA. In the case of RAC, there will be two layers of interfacial transition zone (ITZ). ITZ due to old mortar adhered with aggregate will have greater porosity. Increase in the replacement of natural aggregate with RCA will increase the porosity in the given mass of concrete. This experimental investigation aims at improving the impermeability of RAC by adding chemical admixture which enhances the strength and durability performance.

Conventionally used cement –a primary binder also a necessitate element in producing concrete rates first in the construction industry. Production of conventional cement requires a greater skill and is energy intensive. The usage of waste materials in the production of concrete and reduction in cement content was only the possible alternative in the past decade. Associated risks with the production of Ordinary Portland Cement are well known. A greener aided with a natural friendly claim can be made only with the usage of the waste materials and reduction in evolving respiration gas to the atmosphere. Almost all works are carried out using source material fly ash, with fine aggregate and coarse aggregate. Concrete plays a vital role in the construction industry and on the other hand, river sand; one of the essential material has become very expensive which is a scarce material. Depletion of sand is a hectic issue due to increased usage of sand in construction. No other replacement materials such as quarry rock dust is not concentrated in casting geopolymer specimens. Even though in some research papers the replacement materials are added only in partial replacement without aiming on 100% replacement. Many researches mainly focus towards test results of GPC specimens using steel fibers, glass fibers. But the study related to natural fibers and hybrid fibers are found scarce. The main part of this work aimed at characterizing the engineering strength properties of geopolymer concrete by 100% replacement of fine aggregate with quarry rock dust. Hence, combination of flyash and quarry rock dust in GPC have been considered for evaluating the mechanical properties of geopolymer concrete. Also, investigation focuses on incorporation of three different fibers namely polypropylene fibers(PF), coir fibers(CF) and hybrid fibers(HF) in different percentage of proportions such as 0.5%,1%,and 1.5% to determine the maximum strength properties of GPC.