Properties of pervious concretes including spherical cold-bonded artificial fly ash aggregates

The objective of this paper was to utilize cold-bonded fly ash aggregate in pervious concrete to produce a sustainable lightweight pervious concrete. Artificial lightweight fly ash aggregates were manufactured through the cold-bonding pelletization of 90% fly ash and 10% Portland cement in a tilted pan at an ambient temperature. The pervious concrete in this study was manufactured by the replacing the single sized natural aggregate with single sized cold-bonded fly ash aggregate at five replacement levels of 0, 25, 50, 75, and 100% by total aggregate volume. Two different concrete series were produced at two water-to-cement ratio 0.27 and 0.32. Totally, 10 pervious concrete were produced in this study. The single sized natural and cold-bonded fly ash aggregates were the aggregate passing from 12.5-mm sieve and retaining on 8-mm sieve. The pervious concretes were tested for the compressive and splitting tensile strengths, permeability characteristics and abrasion resistance. Moreover, the dry density and void contents of the pervious concrete mixtures were determined during the experimental study. Besides, the properties of pervious concrete produced with cold-bonded fly ash aggregate were also assessed by statistical technique that is GLM-ANOVA. The experimental results indicated that the use of cold-bonded fly ash aggregate significantly enhanced the permeability coefficient of the pervious concrete while it decreased the mechanical properties of the pervious concrete. In addition, the results indicated that replacing the single sized natural aggregate with artificial cold-bonded lightweight fly ash aggregate decreased the dry density of the concrete mixtures and increased the void content.