Geopolymer Concrete, Mortar, and Paste: A Review

Abstract

The problems of global warming and environmental pollution with gaseous and solid wastes, made researchers think of finding effective alternatives to reduce the proportion of carbon dioxide in the atmosphere and make use of solid waste for iron manufacturing stations and power production stations. Thus, geopolymers are considered one of the most promising solutions in the field of structural engineering. Therefore, this paper presents a review of previous studies on geopolymer mixtures, which were investigated in three main parameters, included: slag addition, solution ratios, adding fibers, and Nano silica. The results of the previous investigation showed that the compressive strength increased with the increase in the slag ratio. At certain proportions, the compressive strength increases with increasing the sodium silicate to sodium hydroxide and increasing the sodium hydroxide concentration (M). While it was reduced fresh properties such as flow-ability and setting time. It was also found that the addition of fibers or Nano silica improved the microstructures of geopolymers, and thus a significant improvement in tensile strength and compressive strength. Finally, the addition of external water was found to improve flow-ability but reduce compressive strength, while the addition of the superplasticizer in certain proportions improves fresh properties.