Impact of nano-alumina on the mechanical characterization of PVA fibre-reinforced geopolymer composites.

In this paper, four groups of polyvinyl alcohol fibre-reinforced geopolymer composites containing various content of nano-alumina particles were investigated. Results showed an improvement in geopolymer fracture toughness, compressive, impact and flexural strength with the added nano-alumina particles as compared to the control specimen. Flexural strength increases as the weight ratio of nano-alumina particles increases from 0.0 to 2.0 wt% and then decreases to 6.50 MPa at 3.0 wt%. Geopolymer reinforced by 2.0 wt% of nano-alumina (PVAGNC-2) displayed the highest flexural and compressive strength of 7.51 and 23.48, respectively. PVAGNC-2 exhibited the highest mechanical (compressive, flexural, impact and hardness) properties. Scanning Electron Microscopy examination showed that the PVAGNC-2 microstructure is compacted with fewer pores indicating the probability of PVAGNC-2 to display great compressive strength and excellent mechanical resistance to the external force needed for construction. [ABSTRACT FROM AUTHOR]