Performance of Recycled Concrete Aggregates- New Era for Use in Construction - A Literature Review

The issues of sustainability are of prime concerns these days as we use large amount of natural resources for producing materials such as concrete. The recent trend in construction industry is to use the alternative source of construction materials which can substitute the use of virgin materials in order to reduce environmental impact in terms of energy consumption, pollution, waste disposal and global warming. The present paper gives a brief status of recycled aggregate concrete made out of recycled aggregate, summarizes and critically analyses some of the most important research findings over the past few years. Most studies have shown that the long-term properties of RAC are inferior to those of natural aggregate concrete (NAC), and some researchers have observed that the long-term properties are better than those of NAC. RAC's properties are affected by many factors such as recycled coarse aggregate (RCA) replacement percentage, water-cement ratio, mineral admixtures and mix proportions. The long-term properties of RAC can be improved through better Control of these factors. This paper will be helpful for an understanding of and further research on RAC, and provides an important basis and references for the engineering applications of RAC.