Use of copper slag in concrete

The present investigation assesses the incorporation of copper slag in concrete. The effect of copper slag as partial replacement of cement on the compressive strength of concrete has been investigated. The hydration of cement with copper slag was investigated through X-ray diffraction (XRD). Five concrete mixes (C0, C5, C10, C15 and C20) were made by replacing cement with 5%, 10%, 15% and 20% of copper slag by mass respectively. The water/cement ratio in all the mixes was kept at 0.43. Results showed that the compressive strength of concrete decreases as CS content increases for all curing ages. The reduction in compressive strength is minor up to 10% of CS but beyond 10% of CS, there is significant reduction in compressive strength due to the increase in free water content in mixes. XRD showed that the 10% of copper slag slightly reduces the hydration of cement, but 20% of copper slag significantly reduces the hydration of cement. It indicates that the copper slag can be utilized as supplementary cement replacement material in concrete. The optimum content of copper slag as replacement of cement is recommended as 10%.