Effect of Copper Slag when Partially Replaced with Fine Aggregate in Concrete

An experimental investigation was conducted to study the effect of using copper slag as a fine aggregate and the effect fly ash as partial replacement of cement on the properties high performance concrete. Totally eight concrete mixtures were prepared. Four mixes containing different proportions of copper slag ranging from 0% (for the control mix) to 65%. Four mixes containing fly ash as partial replacement of cement ranging at 25% constant. Concrete mixes were tested for compressive strength, split tensile strength and flexural strength. The results indicate that there is a increase in the strength about 40% with the increase of copper slag content, whereas the workability increased with increase in copper slag percentage. Addition of up to 45% of copper slag as sand replacement yielded comparable strength with that of the control mix. However, further additions of copper slag caused reduction in the strength due to an increase of the free water content in the mix. Mix with 65% copper slag replacement there is decreased in strengths. For this concrete containing 45% copper slag, fly ash is introduced in the concrete for better strength. Introduction of fly ash gave better results than concrete containing 45% copper slag. Workability got increased with further increase in fly ash content. Therefore, it is recommended that approximately 40% of copper slag can be used as replacement of sand and 25% fly ash can be used as replacement of cement in order to obtain high performance concrete.