Stone dust and recycled concrete aggregates in concrete construction: An efficient way of sustainable development

Abstract

In the last five decades, a continuous research has established that concrete is a versatile material where the different wastes can be consumed for environment friendly sustainable development. The disposal of stone dust and demolished old concrete is becoming a serious issue. To conserve the diminishing natural resources, stone dust and recycled aggregates obtained from crushed rubble can be re-used in building industry. The suitability of stone dust as a fine aggregate and recycled concrete aggregates as coarse aggregate is a topic of research interest for researchers in the past. In the earlier research, the main focus was on taking these wastes separately. The results of concomitant presence of both stone dust and recycled concrete aggregates in concrete and their understanding on the durability performance are lacking. Based on the past research input, an exhaustive experimental program was envisaged to assess the suitability of stone dust and recycled concrete aggregates on strength and durability of concrete of different grades. Two design mixes of M20 and M30 grades were designed using natural aggregates. The equivalent mixes were obtained by replacing natural coarse aggregates by recycled coarse aggregates and natural river sand by stone dust ranging from 0 to 100 percent. An approximately same slump value of different mixes was made by adding varying doses of super plasticizer. The durability of concrete was assessed against sulfate attack and at elevated temperatures. The test results indicate the good prospects of utilizing these wastes in making quality concrete. It was found that the concrete with recycled concrete aggregates as coarse aggregate and 40% replacement of river sand with stone dust provide encouraging results of concrete strength and durability characteristics.