Investigation on Engineering Properties of Waste Foundry Sand

Abstract

Waste foundry sand (WFS) is produced in the metal casting industry when high-quality silica sand is exposed to intense heat (around 1400 °C). This exposure results in the degradation of binders and loss of strength, leading to contamination with heavy metals, which makes it unfit for reuse in moulding processes. As the second-largest casting industry globally, India produces approximately 3 million tons of WFS annually from over 5,000 foundries. This presents a significant challenge for waste management but highlights the potential for sustainable reuse in different engineering fields. Although numerous studies have been conducted on the use of WFS in construction materials, such as concrete and pavements, relatively little attention has been given to its potential applications in geotechnical engineering, including landfills, hydraulic barriers, and its interaction with geosynthetics. Before using any materials in geotechnical engineering, it is crucial to assess their fundamental engineering properties. This study presents the basic engineering properties of WFS as a potential replacement for natural sand, including specific gravity, void ratio, water absorption, compressibility, and shear strength. The characteristics of this material were analysed alongside those of natural sand, and the properties are outlined.