Strength and micro-structural properties of self-compacting concrete incorporating copper slag: Fid-Bau Portal

Strength and micro-structural properties of self-compacting concrete incorporating copper slag

Gupta, Nikita / Siddique, Rafat

Highlights • Utilization of copper slag as partial replacement of fine aggregates in SCC. • Fresh properties enhanced with the addition of copper slag. • Copper slag improves the strength properties of SCC. • Micro-structure of SCC improved on addition of copper slag.

Abstract Copper manufacturing industry produces abundant quantity of copper slag as an industrial by-product. Its management and disposal poses a major challenge for the environment, thus an urgent need for its potential alternative is recommended. The intent of the current research work was to design self-compacting concrete mixes incorporating copper slag as fine aggregate replacement. Compressive strength, split tensile strength along with micro-structural analysis of SCC mixes were conducted for up to 90 days of curing. Linear Regression analysis was executed to correlate the fresh properties of SCC. Flowability and passing ability of SCC mixes enhanced as the content of copper slag increased, at constant water cement ratio and fixed quantity of superplasticiser. Compressive strength and split tensile strength increased as the content of copper slag escalated. SEM, EDS and XRD analysis confirmed the development of calcium silicate hydrate gel in concrete mixes with the progressing curing ages from 7 to 90 days. Analysis of variance (ANNOVA) was used to compare different SCC mixes at 7, 28 and 90 days of curing age. Post hoc Tukey HSB was used for multiple comparision between SCC mixes varying from 0% to 60%. Statistical analysis reported that 28-day and 90-day compressive strength was statistically significant while 7-day compressive strength was found out to statistically insignificant.