Evaluation of coppe slag as aggregate addition on properties of cementitious matrix

Abstract

This work aims the performance of concretes copper slag-added evaluated in fresh state by slump test and in hardened state by compression strength in 7 and 28 days of cement hydration, durability indexes as water absorption and binder efficiency by cement index. In fresh state, the results showed that the samples with copper slag presented lower slump than the reference sample. In hardened state, with 30% of copper slag addition, the compression strength was reduced only by 9% and 8% in comparison with the control series, for 7 and 28 days, receptively. Also, for 28 and 48 days of cement hydration, the water absorption showed lower values in the series with copper slag, indicating a beneficial performance of this waste in the cementitious matrix. Also, the binder efficiency was verified in the work. As the higher the slag in the mixture, lower was the cement consumption and, consequently, higher was the efficiency of the cement, resulting in a low increased in the cement index. The control series, at 28 days of cement hydration, achieved 11 kg·m-3·MPa-1 while the 30% copper slag-added series achieved 12 kg·m-3·MPa-1, which is only 9% higher than series with no consumption of copper slag, indicating a great performance of the copper slag in this cementitious matrix.

Keywords: copper slag; cementitious matrix; replacement; concrete.