Systematic review on the use of waste foundry sand as a partial replacement of natural sand in concrete

Waste foundry sand (WFS) is a by-product of the metal casting process, which constitutes a sustainable solution as a replacement for natural sand (NS) in the production of concrete. This article provides an overview of two types of WFS, along with their physical and chemical properties. The present research highlights the potential applications of WFS in mortars, concrete, and self-compacting concrete (SCC). In addition to examining the influence of WFS substitution on workability, mechanical properties, and durability. The literature consulted indicates that the workability, mechanical properties, and durability of mortar, concrete, and SCC may be affected when increasing the substitution of NS with WFS. However, in some cases, WFS can offer comparable or improved mechanical and durability properties to NS. It has been observed that in some studies, impurities in the form of clay particles, dust, and phenolic resins of the WFS particles are the reason for the resulting decrease reported in workability, mechanical properties, and durability. Few studies report durability in terms of ultrasonic pulse velocity (UPV), freeze-thaw resistance, abrasion, chloride penetration, and sulphate resistance, which is a research gap that should be addressed. Moreover, the use of WFS is a viable alternative to NS, leading to a more sustainable and environmentally friendly approach for the construction industry.