Low-Carbon Self-Compacting Concretes Incorporating binary Ternary and Quaternary Cementitious Blends: Synergistic Effects of Marble Powder, Metakaolin, and Silica Fume

Naima.HADDADOU 1 Sabria-M.MANSOUR 2 Youcef.GHERNOUTI 3 Amine,H.DAGHMOUM 4 Rabah.CHAID 5 Abstract: Self-compacting concrete (SCC) necessitates elevated powder content, resulting in heightened cement usage and environmental repercussions. This study examines a low-carbon methodology by partially substituting cement with marble powder (MP), silica fume (SF), and metakaolin (MK) to diminish clinker consumption and improve sustainability. Eighteen SCC combinations were developed utilizing binary, ternary, and quaternary blends with total replacement levels ranging from 5% to 45%, maintaining a constant water-to-binder ratio of 0.34. New properties were evaluated by slump flow, L-box, air content, and sieve stability tests, while mechanical and durability performance were measured using compressive and flexural strength, ultrasonic pulse velocity (UPV), drying shrinkage, water absorption, and sulfuric acid resistance. The findings indicate that ternary mixtures including 15% MP and 15% SF yielded the optimal equilibrium of flowability, passing ability, and segregation resistance. A compressive strength of 46 MPa was attained at 56 days, corroborated by elevated UPV values signifying dense microstructures. MP diminished drying shrinkage, but SF and MK marginally augmented it owing to their pozzolanic properties. Durability markedly increased with the incorporation of mineral additives up to 30%, resulting in significant decreases in water absorption and greater resistance to sulfuric acid corrosion. The integration of MP, SF, and MK enhances both fresh and hardened performance while reducing the carbon footprint of SCC. The results indicate that optimized ternary mixes provide an effective approach for generating sustainable, high-performance self-compacting concrete (SCC) appropriate for structural and infrastructural uses.