Effect of Aggregate Size on Mechanical Behavior and Pore Structure Features of the Pervious Concrete

Pervious concrete (PC), with its interconnected voids, facilitates water percolation, reduces runoff, and enhances groundwater recharge. This study examines the relationship between aggregate size and both compressive and splitting tensile strength, along with an investigation of its pore structure features using MATLAB‐based image analysis. A total of 12 mix proportions without supplementary additive and nine with additives were evaluated. The compressive strength of PC without additives ranges from 3.23 to 9.21 MPa, with smaller aggregates generally yielding better strength due to increased bonding surface area. The inclusion of the supplementary additives, such as fly ash, silica fume, and superplasticizers further enhance the strength reaching upto 14.43 MPa, with the effect of aggregates size being more pronounced at lower void contents. Splitting tensile strength was approximately 15% of compressive strength, following the similar trend with aggregate size. Additionally, image analysis of pore structure revealed that while permeability generally increases with porosity, it is more strongly influenced by the spatial distribution of the voids rather than total porosity.