Estimation of strength, permeability and hydraulic diffusivity of Pozzolana blended concrete through pore size distribution

Abstract

The compressive strength, permeability and hydraulic diffusivity of Ordinary Portland Cement (OPC) with or without pozzolana blended concrete have been estimated in this investigation by using Mercury Intrusion Porosimetry (MIP). With this in view, concrete cubical specimens were crushed and the broken chunks with aggregates were collected from different mixes such as OPC mix, OPC with silica fume (5%, 10% and 15% of replacements) mix and OPC with slag (10%, 30% and 50% of replacements) mixes. The MIP experimentation was carried out for wide range of curing ages such as 1, 3, 7, 28, 42 and 90 days. The experimental Pore Size Distribution (PSD) parameters such as mean distribution radius (r0.5), dispersion coefficient (d) and permeable porosity (P) for all mixes were calculated by using the Morgan Mercer Flodin (MMF) model. The application of experimental PSD parameters is demonstrated by estimating the com-pressive strength, permeability and hydraulic diffusivity through the readily available corresponding relationships in the literature. It is observed that the lowest r0.5 and high d values are obtained in case of OPC with silica fume mix as com-pared to other mixes owing to its better pore refinement. It is observed that the estimated permeability increases with an increase in w/c ratio and decreases with an increase in curing ages which resembles the trend of Powers’ permeability versus w/c ratio curves.