Durability and mechanical properties of precast concrete curb containing waste copper slag

Abstract

Copper slag is a by-product which has been widely used in several industries. After being used for abrasive tools, it is discarded in the environment where it can have a harmful impact. The size of copper slag particles ranges up to a diameter of 3 mm, and is of a relatively similar size to fine sand, for which it could therefore be substituted in the production of precast concrete curbing. To this aim, the strength and the durability of curbing were evaluated through a series of tests on six different proportions of waste copper slag ranging from 0 to 100% replacement of fine sand. It is concluded that substituting 40% of fine sand with waste copper slag yields the best mechanical and durability properties. By replacing this proportion, the compressive and bending strength of concrete increased by almost 30% and 14%, respectively. However, a slight effect was found in the total water absorption and abrasive resistance. The freeze–thaw resistance of concrete curbs increased significantly after a 20% replacement by waste copper. This study reveals that it is possible to substitute fine sand with waste copper slag without any negative effect on the properties of the curbing.