ABSTRACT. The recycling of concrete rubble can contribute in reducing the total environmental impact of the building sector. In this research, recycled coarse aggregate (RCA) obtained from destroyed buildings in Libya were used to produce a new concrete by replacing Natural aggregate (NA) by (RCA) in the concrete.
Abstract. The search use different ratios (, 75%, 50%,and 25%) of river sand as a substitute for mine sand as a fine aggregate, due to its availability, in four Concrete mixtures, while the fifth mixture was without river sand, in which sand from (Al – Akhthere) mine was used as a fine aggregate and took as a referential mixture.