Microstructure Analysis of Concrete with Pulverized Used Foundry Sand as Mineral Admixture

Abstract

There are several mineral admixtures used in concrete to enhance its properties. Pulverized used foundry sand (PUFS) is a recently introduced patented material into the mineral admixture category. The pulverized used foundry sand is made from the discarded waste foundry sand generated from the foundry operations. In this paper, an effort is made to investigate the different micro structure analysis methods employed in the elemental study of mineral compounds and to accentuate the strength enhancement mechanism of the pulverized used foundry sand in concrete. Representative samples obtained from concrete comprising pulverised used foundry sand content at 0%,5%,10%,15%, and 20% of the cement content by weight as per standard practice were tested with EDX (Energy Dispersive X-ray), SEM (Scanning Electron Microscope). EDX, SEM and XRD (X-Ray Diffraction) analysis were conducted on pulverized used foundry sand and silica fume for studying the various elements and its proportions. From the SEM images it is ascertained that the addition of PUFS increases the quantities of CSH (Calcium Silicate Hydrate) and Calcite in the concrete. As an outcome, the microstructure analysis of concrete having different proportions of PUFS portrays how the PUFS as a mineral additive affects the strength characteristics of concrete that contains it.