Tropical-friendly self-compacting concrete: fresh, mechanical and durability performance using Indigenous Sudanese Arabic gum, limestone powder and natural pozzolan

This paper investigates the performance of three types of Self-compacting concrete (SCC) mixes containing ordinary Portland cement (OPC) with different additions of Arabic gum (AG), limestone powder (LSP), and natural pozzolan (NP) to achieve self-compactability. To minimize generated hydration heat, these materials reduce 400 kg/m³ OPC content up to 15% by weight. Primarily, the SCC fresh properties tests are carried out on 22 trial mixes with various water/powder (W/P) ratios to achieve the optimums fresh performance. Then six SCC mixes are selected and, furthermore, tested for extra fresh and hardened SCC properties, including durability against sulfate attack and chloride ingress. The findings indicate that SCC containing 0.2% AG exhibited superior fresh behavior and mechanical performance compared to other mixtures. Additionally, NP incorporation increased shrinkage, whereas LSP enhanced sulfate resistance by reducing surface erosion. In terms of chloride ingress, SCC with 0.2% AG demonstrated improved resistance, while the inclusion of 15% LSP negatively affected chloride penetration resistance. These results provide valuable insights into the potential of AG, LSP, and NP as sustainable alternatives for enhancing SCC performance.