Utilization of nano WPSA as supplementary cementitious material in enhancing properties of self-consolidating high-performance concrete

Self-consolidating high-performance concrete (SCHPC) has been extensively studied, but the incorporation of nano waste elements remains largely unexplored. This research aims to innovate SCHPC by introducing Nano Waste Paper Sludge Ash (NaWPSA) as a Supplementary Cementitious Material (SCM), a novel material. Experimental investigations assess the properties and performance enhancements of SCHPC with NaWPSA. The study's objectives include producing and analyzing NaWPSA properties, developing an optimal SCHPC mix, incorporating varying percentages of NaWPSA, and measuring the resulting mechanical, chemical, and durability properties. The final objective involves evaluating NaWPSA's effects on SCHPC using software analysis. Findings indicate that NaWPSA, primarily composed of CaCO3 and CaO, has a particle size of 5.615 nm and smooth, rounded surfaces. The optimal SCHPC mix was determined to contain 1000 kg/m³ cement with a 0.2 water-to-cement ratio. The best compressive strength and flow were achieved with a 1% NaWPSA replacement. This mix also exhibited the highest splitting tensile strength and no visible carbonation after one year. SEM analysis revealed NaWPSA's role in forming ettringite needles and WPSA flakes. Additionally, NaWPSA SCHPC outperformed others in flexural strength and deflection tests. Mathematical models confirmed a clear correlation between compressive and splitting tensile strengths. This research enhances the understanding of SCHPC, WPSA, and nano materials, offering valuable insights for future studies and practical applications in high-performance concrete.