Flexural behaviour of reinforced one-part geopolymer concrete beams

Abstract

The recent development of “one-part geopolymer” has significantly improved construction safety and convenience, establishing it as a highly promising new type of low-carbon binder with performance comparable to traditional cement. This study investigated the flexural performance of reinforced concrete (RC) beams made from one-part geopolymer concrete (OPGC), in comparison to conventional ordinary Portland cement (OPC) concrete beams. The microstructure of OPGC and conventional concrete were firstly compared. Four-point bending tests were then conducted on nine beams, including three OPC concrete beams and six OPGC beams. The influence of longitudinal reinforcement ratio on the flexural performance of OPGC beams was examined, and the bending performance of OPGC beams and OPC concrete beams was compared. Experimental results revealed that OPGC beams exhibited similar flexural performance to those cast with OPC concrete in terms of cracking development, failure modes, load-deflection curves, and strain distribution. In addition, an analytical model for estimating the flexural capacity of OPGC beams was proposed and validated against experimental results. Finally, the environmental and economic indices between the OPGC and OPC concrete beams were compared and analysed. This research provides valuable insights for the design and analysis of OPGC structural members.