Grade-dependent performance of zinc slag aggregate in concrete: Optimisation through multi-property statistical analysis

초록

The current study investigates the application of zinc slag (ZS), a by-product of the zinc smelting industry, as a potential alternative fine aggregate for concrete production. The study experimentally evaluated the short-term performance of ZS as a fine aggregate replacement in two concrete grades at replacement levels of 0%, 30%, 50%, and 100%. To achieve a target slump of 180 mm, the mixing water content was adjusted for each mixture, resulting in different effective w/c ratios across the investigated mixes. Fresh properties (slump and air content), compressive strength, carbonation depth upto 16 weeks, and drying shrinkage upto 30 days were assessed. All mixtures achieved the target workability range while requiring progressively lower water contents as ZS replacement increased. The incorporation of ZS generally maintained acceptable air contents and produced comparable or improved mechanical and durability-related performance, particularly in the higher-strength concrete mixtures. Pearson correlation analysis was used to examine relationships among mix design parameters and measured performance indicators, while entropy-weighted grey relational analysis (GRA) was applied as a comparative multi-criteria assessment tool. The highest grey relational grades were obtained at 50% ZS replacement for NSC and 100% ZS replacement for HSC, indicating favourable overall performance within the investigated experimental conditions. The findings suggest that ZS can be utilised as a fine-aggregate replacement in concrete while maintaining satisfactory fresh, mechanical, and durable properties. However, the conclusions are limited to the short-term performance indicators considered in this study, and further investigations involving long-term durability and microstructural characterisation are required to validate the observed trends. © 2026 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license. http://creativecommons.org/licenses/by/4.0/

키워드