Influence of physico‐mechanical and electrical resistivity performance of high volume fly‐ash cementitious mortar with low carbon

Abstract

AbstractA graphene oxide (GO) has the potential to improve the strength and hardness of cementitious matrix. The agglomeration of GO in an alkaline medium of cement matrix reduced the reinforcing efficiency. In this study, two types of control samples were fabricated named OPC‐C (OPC control) and HVFA‐C (OPC + 50% FA control) without the addition of GO and four HVFA cementitious mortar samples HVFA‐G1, HVFA‐G2, HVFA‐G3, and HVFA‐G4 were prepared with incorporation of GO 0.005%, 0.010%, 0.020% and 0.040%, respectively. The results revealed that the superplasticizer stabilized GO in cement mortar, significantly improves the compressive (27.12%) and split tensile strength (38.16%) in the HVFA‐G3 mix as compared to HVFA‐C at a curing age of 90 days. The maximum electrical resistivity attained in HVFA‐G4 (83%) mix as compared to OPC‐C at a curing age of 90 days. In addition, microstructural analysis of HVFA cementitious mortar was conducted using a Field Emission‐Scanning Electron Microscope (FE‐SEM), while the crystallization behavior of hydration products ware examined through Powdered X‐Ray Diffraction (PXRD). Furthermore, the chemical bonding between the hydration products was studied using Fourier Transform Infrared Spectroscopy (FT‐IR). Overall, it is concluded that the superplasticizer stabilized GO in HVFA cementitious mortar, helps to achieve better mechanical strength, electrical resistivity performance, and microstructural behavior.