Experimental Study on Recycled Aggregates Concrete Using Water Reducing Admixture

Abstract

Today, the construction sector generates a significant volume of demolition waste as a result of ongoing reconstruction and redevelopment projects. Getting rid of this waste has turned into a significant environmental issue. Meanwhile, the use of natural aggregates in concrete is steadily declining due to extensive construction activities. To address these issues, Recycled Concrete Aggregates (RCA) can serve as a substitute for natural aggregates in concrete.

For this project, recycled aggregate concrete was produced by substituting natural coarse aggregate with 0%, 25%, 50%, and 75% recycled aggregate. A water-reducing admixture was also incorporated to enhance workability and strength. Concrete cube specimens were subjected to compressive strength tests following 7 days of curing. The results of the experiment indicated that compressive strength declines with a higher percentage of recycled aggregate. Replacing 25% of the concrete with RCA yielded results nearly equivalent to normal concrete and outperformed the 50% and 75% replacement levels. This study demonstrates that recycled aggregate is suitable for use in concrete, supporting sustainable and environmentally friendly construction.