Performance analysis of recycled aggregate concrete with chemical admixture

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.