Influence of Supplementary Cementitious Materials and Coarse Aggregates on Properties of the No Fines Concrete

Abstract

The rapid increase in infrastructural development escalates the problem of storm water runoff and flash flooding in rainy seasons in urban areas due to insufficient drainage. To overcome this problem, the permeability of conventional pavements is improved by replacing normal concrete with Pervious Concrete or No-Fines Concrete (NFC). Since NFC consist of extensive large volume of voids which contributes towards its highly porous nature, which can remedy the problem of the rainwater runoff, recharges the groundwater table near road pavements, city streets, and parking lots, and reduces noise from the vehicle tire movement. The exclusion of sand from NFC leads to a reduction in workability and strength, limiting its practical applications. Thereby, it is currently not feasible to use NFC mixtures in highway pavements due to their lower strength than conventional pavement quality concrete. This research aimed to investigate the influence of supplementary cementitious materials such as fly ash, metakaolin, silica fume, and rice husk ash and different gradations of coarse aggregates on the properties of NFC. In NFC mixes, cement was replaced by supplementary cementitious materials up to 20% replacement levels. The effect of different gradations of coarse aggregates on the properties of NFC was also inspected. The following properties were evaluated: compressive strength, split tensile strength, flexural strength, abrasion resistance, water permeability, porosity, density, water absorption, and drying shrinkage up to 365-day. The experimental results indicate that with the inclusion of Fly Ash (FA), the compressive strength decreased at an early curing age up to 28-day compared to the control NFC mix. The compressive strength increased concerning the control NFC mix at 90 and 365-day of curing. With the incorporation of metakaolin in the NFC mix, the compressive strength increased with the increasing percentage replacement of Metakaolin (MK) at all curing ages compared to the control NFC mix.