摘要：Natural resources are being continuously extracted for the production of concrete which leads to degradation of the ecosystem. This is also a challenge for sustainability to save Nature. This study seeks to identify a suitable replacement material for river sand and stone aggregate for the sustainable utilization of renewable sources. Manufactured sand (M-sand) from industrial by-products and coconut shell (CS), an agricultural waste, are the resources selected as replacement materials for sustainability. This study uses M-sand as fine aggregate and CS coarse aggregate in place of river sand (R-sand) and crushed stone aggregate (CSA) for concrete production, respectively. To prove that M-sand and CS are sustainable alternate materials, this study focused on the microstructural characteristics on concrete constituents and CS aggregate and also conducted on concrete produced using R-sand, M-sand and CS. Also, this study focused on the microstructural characteristics and properties of conventional concrete (CC) and coconut shell concrete (CSC) produced using both R-sand and M-sand. Since this study aims to find sustainable alternative materials for R-sand and CSA by M-sand and CS, its properties are studied and compared since microstructural characterization is very significant for concrete compatibility. Microstructural studies revealed that the use of M-sand does not affect the microstructural properties of concrete compared to R-sand concrete and rather it improves the strength of concrete. A similar same trend was observed when CS was used with M-sand compared to CS used with R-sand. Hence, this study strongly suggests that the use of M-sand in its place of R-sand and CS in its place of CSA are sustainable alternatives for the production of concrete so that natural resources can be saved and hence sustainability could be sustained.
