A Comprehensive Experimental Investigation of Fly-Based Geopolymer Concrete Made with Recycled Concrete Aggregates

This study explores the potential utilization of construction and demolition waste through the incorporation of Recycled Concrete Coarse Aggregates (RCCA) and Recycled Concrete Fine Aggregates in Fly Ash (FA) based GeoPolymer Concrete (GPC). It is important to expand the use of construction and demolition waste in the form of RCCA and RCFA in GPC as a new-generation concrete. In the future, GPC can replace conventional concrete, which will help to reduce carbon footprint by lowering the need for Portland Cement (PC). Moreover, Recycled Concrete Powder (RCP) was also utilized along with FA as a binary binder to enhance the performance of GPC. The experimental investigation includes various tests such as compressive strength test, Capillary Suction Test (CST), Initial Surface Absorption (ISA) test, acid attack test, Ultrasonic Pulse Velocity (UPV) test, and electrical resistivity test. The microstructural study was also done through a Scanning Electron Microscope (SEM) test for GPC mixes. The results of the experimental investigation revealed that the inclusion of RCCA and RCFA may have a detrimental effect on GPC performance, but the presence of RCP helps to mitigate this impact. Nevertheless, the study suggests incorporating 25% RCFA along with 100% RCCA and 30% RCP can be considered in GPC, as they exhibit lesser deterioration. Consequently, the utilization of construction and demolition waste in the form of RCCA and RCFA, along with RCP, not only presents an economic advantage but also contributes to achieving a sustainable environment. © The Author(s), under exclusive licence to Shiraz University 2024.