Performance Evaluation of High-Strength Concrete with Silica Fume and Metakaolin as Cement Replacements
Description
Abstract The increasing demand for high-performance and sustainable construction materials has driven the exploration of supplementary cementitious materials (SCMs) as partial replacements for cement in concrete. This study investigates the performance of high-strength concrete (M50 grade) incorporating silica fume and metakaolin as partial cement replacements. Silica fume, a by-product of silicon alloy production, was used at replacement levels of 5%, 7%, and 10%, while metakaolin, a calcined clay material, was used at 10%, 15%, and 20% replacement levels. Mechanical properties, including compressive strength, split tensile strength, and flexural strength, were evaluated after 7, 14, 28, and 56 days of curing, while durability was assessed through water absorption tests. Workability was measured using the slump test, and surface hardness was determined using the rebound hammer test, with all tests conducted as per Indian Standards. The results revealed significant enhancements in concrete performance with both materials. Optimal compressive strength was achieved at 7% silica fume and 15% metakaolin replacements, showing improvements of 8% and 10%, respectively, over the control mix. Tensile and flexural strengths followed similar trends, while water absorption decreased significantly, with reductions of up to 29%. However, workability decreased with increasing replacement levels, which was effectively mitigated using a superplasticizer. The study concludes that silica fume and metakaolin are effective SCMs for enhancing the mechanical and durability properties of high-strength concrete while contributing to sustainability by reducing cement consumption. These findings provide valuable insights for the construction industry, paving the way for more durable and environmentally friendly infrastructure.
Files
Institutions
- Chandigarh University