A mathematical model for strength prediction of HPC containing copper slag as a cementitious material

Abstract

High-performance concrete (HPC) encompasses cement, copper slag, sand, coarse aggregate, superplasticizer, and water. The strength of HPC is determined by the specific surface area of supplementary cementitious materials. Hence it is interesting to investigate the effect of copper slag as a cement replacement on the strength of HPC. In this study, three-level of water-to-cement ratios (0.3, 0,4, and 0,5) were chosen. The various concrete mixtures are produced with increasing copper slag contents from 0 to 40 wt.% in steps of 10 wt.% as cement replacement. To obtain two levels of fineness, the copper slag was milled using a ball mill. The result shows that the strength of concrete containing copper slag for all water-to-cement ratio was lower than the control mixture at an early age (7 days). For the longer curing periods (28 days), the compressive strength of concrete was similar or slightly higher compared to the reference mixture at the replacement level up to 20% for two-level of fineness. A new model, according to Abrams Law, which is Abram-RET, is being proposed by the author to predict the compressive strength of high-performance concrete at 28 days, which gives a strong correlation with the experimental results.