Behavior and Correlations between different Mechanical Properties of Fly Ash-based Geopolymer Concrete

Abstract

Undoubtedly, the interest in using Geopolymer Concrete (GPC) recently speared. Hence, it's essential to study the behavior of GPC. In the current research, the mechanical properties of GPC were studied to investigate the performance at the time interval of 28 days to 90 days. The study extended to include water absorption, water permeability, and sulfate attack tests. The experimental work program was conducted to cover the effect of the curing method (steamer with 60°C or warm air) in addition to the curing period (seven days or three days). Also, the bond strength was investigated between steel reinforcement bars and concrete. Furthermore, the GPC ingredients were captured internally using a scanning electron microscope (SEM) to analyze their integrity. The results showed that the recorded slump value of the GPC mixture was more than the conventional concrete (CC) mixture by 130%, afterward the GPC mixture became stickier, and hardening happened. The GPC mixtures achieved significant enhancement, and the strength was highly developed after 28 days more than CC, especially for GPC cured in a steamer at 60°C for seven days, which reached the limits of high-strength Geopolymer Concrete (HSGPC) after 90 days.