Implication of pore size distribution parameters on compressive strength, permeability and hydraulic diffusivity of concrete

In this study, compressive strength, permeability and hydraulic diffusivity of three different grades of concrete have been estimated through pore size distribution (PSD) parameters by using mercury intrusion porosimetry (MIP). For this purpose, cubical concrete specimens are crushed and the broken concrete chunks with aggregates are collected from different grade of concrete mixes such as M20, M30 and M40. These concrete specimens are tested at wide range of ages such as 1, 3, 7, 28, 56 and 90 days of curing. From the cumulative intruded volume versus pressure data obtained from MIP experimentation, the experimental pore size distribution parameters such as mean distribution radius (r0.5), dispersion coefficient (d) and permeable porosity (P) are calculated. The estimated PSD parameters are used to estimate the compressive strength, permeability and hydraulic diffusivity through the readily available relationships for compressive strength, permeability and hydraulic diffusivity.

► The engineering properties of concrete can be determined through the PSD parameters.
► The r0.5 decreases with an increase in curing ages as a result of pore refinement.
► The r0.5 decreases with decrease in w/c ratio.
► The dispersion coefficient increases with an increase in curing ages.
► The dispersion coefficient increases with decrease in w/c ratio.