Mechanical properties and durability of cement-stabilised macadam incorporating waste foundry sand

Abstract

ABSTRACT The reuse of solid waste as a construction material can increase the recycling percentage of solids. Waste foundry sand (WFS), a waste material from casting, provides valuable advantages, such as enhancing environmental protection and reducing economic pressures in cement-stabilised macadam (CSM). The objective of this study was to investigate the effects of WFS on the performance of CSM. Macroscopic experiments and a microstructure analysis were performed for CSM with WFS. Natural fine aggregates were replaced with WFS at 0, 5,10, 15, and 20% by mass. To assess the performance of the CSM with WFS, tests were performed on the unconfined compressive strength (UCS), splitting tensile strength (STS), modulus of elasticity (MOE), frost resistance, and drying shrinkage. The results indicate that the mixture properties are reduced with the addition of WFS, and improve with increasing curing age and cement dosage. Considering the performance and economic cost, the best cement dosage is 4%, and the optimum WFS replacement level for the natural fine aggregate is 15%. Scanning electron microscopy (SEM) provides a proof of the experimental results. Hence, the use of CSM with WFS can be considered as very important for promoting green construction.