Mechanical properties, pozzolanic activity and volume stability of copper slag-filled cementitious materials

Abstract

Copper slag is a by-product waste during copper pyrometallurgy. The piling-stack of copper slag not only occupies a large quantity of plowland, but causes potential danger for local residents. In order to reduce the storage of copper slag, this study prepared concretes by replacing ordinary cement by copper slag. The mechanical properties, phase composition, micrographs, pozzolanic activity and volume stability of the compound cementitious materials were evaluated with fly ash as control. It was found that when the content of copper slag was 5%-10%, the best mechanical properties of concretes were obtained. The phase composition of hydration products of copper slag and fly ash based cementitious materials was almost identical. The micrographs and pozzolanic activity showed that copper slag had stronger reactivity than fly ash. Copper slag based pastes had good volume stability. Copper slag presented a potential application in mortars and concretes.