Estimation of the experimental relationship between compressive strength and electrical resistivity of permeable concrete surface for use in roads and bridges decks drainage

Permeable concrete or porous concrete, due to its interconnected cavities, allows high-speed ‎water to pass from the surface to the lower layers. Although one of the main characteristics of ‎conventional cement composites is their impermeability, permeable concrete can be used for ‎special applications such as parking and road pavements. According to the issues associated ‎with the use of impermeable surfaces in cities such as storm water runoff and improper water ‎supply to groundwater aquifers, it is anticipated that in near future a rise in permeable ‎concrete applications will occur. In this research, permeable mortar specimens containing ‎different replacement values of silica fume (up to 20%) were fabricated. To evaluate the bond ‎between aggregates and cement paste in permeable pavements, electrical resistivity of ‎permeable‏ ‏mortars cured in two different conditions namely lime-water and NaCl solution ‎was measured. The tests including compressive strength, electrical resistivity and permeability ‎were performed on the specimens. The aim was to find a balance between mechanical and ‎hydraulic properties of permeable‏ ‏mortars and extracting a relationship between compressive ‎strength and electrical resisitivty of such cement composites. Results showed that specimens ‎containing coarser aggregate had better performance in compressive strength and electrical ‎resistivity tests. Also, the processing of samples in salt water greatly reduced the electrical ‎resistance of the samples, so that even after 90 days of processing, the samples rarely showed ‎resistance above 10 Ω.m. A meaningful linear correlation was found between electrical ‎resistivity and compressive strength of permeable ‎mortars.‎