Effects of hybrid metallic wastes on strength and durability of cementitious mortars

The amount of industrial waste is increasing along with the rise in industrial production. Therefore, reusing or recycling this harmful waste is quite a significant issue for waste management. A suitable use for industrial wastes is to incorporate them in concrete, the most widely used material in the world. In this study, grinding swarf, which had not been used in cementitious composites before, and metal shavings produced in the computer numerical control (CNC) milling process were used. The effects of these wastes on the strength and durability of cement mortars were investigated by using them separately and in hybrid forms. Flowability, fresh unit weight, compressive strength, flexural strength, water absorption and high-temperature effect tests were conducted on mortar samples. Although the wastes exhibited a positive contribution when used alone, they yielded the highest contribution when combined. When the waste materials were used in a hybrid form, they increased compressive strength, flexural strength and high-temperature resistance by 29%, 12.98% and 49.50%, respectively. Owing to their physical and chemical composition, metal shavings showed fibre effects, while grinding swarf improved strength and durability.