Experimental investigation on Utilization of Pozzolanic By-Products in Porous Concrete

ABSTRACT: Porous concrete is recognized as a sustainable infrastructure alternative for urban environments, employed in permeable pavements to alleviate runoff and enhance aquifer recharge. However, the lack of standardized guidelines for mix optimization and pavement design presents a significant barrier to its wider adoption. To promote sustainability, replacing a fraction of cement with pozzolanic by-products which are treated as supplementary cement replacement materials (SCM), such as fly ash, GGBFS, zeolite, and silica fume, has demonstrated effectiveness in augmenting durability and reducing environmental impacts. This research investigates these four pozzolanic by-products as potential cement alternatives in the development of porous concrete mixtures. Standard size cubes and beams of porous concrete have been produced, and tests for compressive and flexural strength to evaluate the efficacy of the cement replacement materials. The optimal percentage of cement replacement for all four by- products has been determined through comprehensive experimentation and validated through literature analysis. The void ratio of the standard mix proportions has been assessed to ensure the permeability of the composite material. Zeolite and silica fume display superior performance in strength metrics compared to fly ash and GGBFS. The inclusion of admixtures is crucial in enhancing the workability and strength characteristics of porous concrete.