Construction and demolition waste generation has exceedingly increased around the world. in The World about 40% of construction and demolition waste is generated annually. Out of various types of construction and demolition waste, concrete constitues about 80% of the total waste. Therefore, it is necessary to recycle concrete waste to recycled aggregate and recycled aggregate concrete.

A two-stage mixing approach was developed to improve the quality of recycled aggregate concrete for high-grade applications. Experimental results showed that the optimal performance of aggregate concrete using the two-stage mixing approach occurs by using about 20% recycled aggregate substitution