Development of sustainable modified sand concrete: An experimental study

The present study aims to develop 4 types of sustainable modified sand using various proportions of desert sand, natural crushed sand, and recycled crushed sand. The physicochemical characteristics of modified sand have been evaluated. Newly developed modified sand was used to prepare 4 concrete mixes. Further, ordinary Portland cement (OPC) was partially replaced by silica fume (SF), and 4 mixes were made using 12.5% of SF. Experimental results show that all 8 mixes fulfilled the requirements of the ACI 318-08 code. The compressive strength significantly increased with the SF combination at later ages beyond 28 days. It can be concluded that the proposed sustainable modified sand successfully replaced the river sand in concrete manufacturing. Furthermore, 12.5% OPC replacement with SF helps to enhance the concrete strength and reduce the carbon footprint. Detail study must be carried out for the durability of the same design mix concrete.