EXPERIMENTAL STUDY ON HIGH-STRENGTH SULFATE-RESISTING CONCRETE WITH HYBRID LC3 AND SUPERPLASTICIZERS

Concrete structures in the Arabian Gulf endure harsh environmental conditions, including high humidity, elevated temperatures, and significant chloride and sulfate concentrations in soil and groundwater, which accelerate deterioration. Sulfate-resisting cement (SRC), characterized by its low C3A content, has been effective in mitigating these challenges. However, the cement industry is responsible for 5-8% of global CO₂ emissions, highlighting an urgent need to balance durability with sustainability in concrete production. Limestone calcined clay cement (LC3) has emerged as a viable alternative, capable of reducing carbon emissions by up to 40% due to its lower clinker content and less energy-intensive production process. This study investigates the feasibility of combining SRC with calcined clay and limestone powder, along with different types and dosages of superplasticizers, to produce high-strength LC3 concrete suitable for aggressive environments. The results demonstrate that polycarboxylate superplasticizers, especially Fluidum PC314, enhance the hydration, strength, and durability of both SRC and LC3 mixes. These mixes also showed reduced water absorption and drying shrinkage. SEM analysis revealed a dense microstructure, further supporting the positive impact of the incorporated superplasticizers on the performance of these concrete blends.