Hyper-plasticizer dosed concrete pavers containing fly ash in lieu of fine aggregates - A step towards sustainable construction

Abstract

This study was aimed at exploring the possibility of utilizing Class-F fly ash (FA) as fine aggregate in concrete pavers in the presence of a novel hyper-plasticizer. A control mix containing 350 kg/m3 of OPC53 cement and w/c ratio 0.4 was prepared with river sand and aggregates for M40 grade concrete pavers. Fine aggregate replacement with FA was carried out at 25%, 50%, 75%, and 100% and upon achieving the required degree of workability, the physio-mechanical properties of concrete were determined. Durability studies were also carried out to ascertain the long-term behaviour of the concrete pavers under design exposure conditions. The pavers containing FA as complete substitute to river sand exhibited superior performance as compared to the control mix. There was a substantial increase of 35.36%, 9.10%, and 13.85% in the 3-day compressive strength, flexural strength and split tensile strength respectively with a 53.2% decrease in the water absorption. The denser packing and inter-locking observed in the samples containing FA also provided them with an increased abrasion resistance which is crucial for concrete pavers.

Keywords

• Fly ash
• Concrete Pavers
• Sustainability
• Hyper-plasticizer
• Life cycle assessment