Edge-oxidized graphene oxide (EOGO) is a nano-sized material that is chemically stable and easily mixed with water due to its hydrophilic properties; thus, it has been used in various engineering fields, particularly for the reinforcement of building and construction materials. In this study, the effect of EOGO in soil reinforcement was investigated. When mixed with soil, it affects the mechanical properties of the soil–GO mixture. Various amounts of the GO (0%, 0.02%, 0.06%, 0.1%) were added into the sand–clay mixture, and their geotechnical properties were evaluated via multiple laboratories testing methods, including a standard Proctor test, direct shear test, compressibility test, and contact angle measurement. The experimental results show that with the addition of EOGO in soil of up to 0.06% EOGO, the compressibility decreases, the shear strength increases, and the maximum dry density (after compaction) increases.

In this study, edge-oxidized graphene oxide (EOGO) was used as an additive in fly ash (FA) geopolymer paste. The effect of EOGO on the properties of the fly ash geopolymer was investigated. EOGO was added to the FA geopolymer at four different percentages (0%, 0.1%, 0.5% and 1%), and the mixture was cured under two different conditions: room curing (~20 °C) and heat curing (~60 °C). To characterize the FA-EOGO geopolymer, multiple laboratory tests were employed, including compressive strength, Free-Free Resonance Column (FFRC), density, water absorption, and setting tests. The FFRC test was used to evaluate the stiffness at small strain (Young’s modulus) via the resonance of the specimen. The mechanical test results showed that the strength and elastic modulus were high during heat curing, and the highest compressive strength and elastic modulus were achieved at 0.1% EOGO. In the physical test, 0.1% EOGO had the highest density and the lowest porosity and water absorption. As a result of the setting time test, as the EOGO content increased, the setting time was shortened. It is concluded that the optimum proportion of EOGO is 0.1% in FA geopolymer paste.

Geopolymer concrete uses a geopolymer binder instead of traditional Portland cement; thus, it reduces carbon emissions by a significant amount. In this study, Edge-Oxidized Graphene Oxide (EOGO), a carbon-based nanomaterial, was added into a metakaolin-based geopolymer, and its effect on the mechanical and rheological properties of the mixture was investigated. EOGO was added into the mixture at 0% (control), 0.1%, 0.5%, and 1% of the metakaolin mass. Several experiments were conducted to characterize the properties of the metakaolin–EOGO (MKGO) geopolymer, including its compressive strength, free–free resonance column (FFRC), void content, water absorption, setting time, flow, and rheology. It was found that the compressive strength and stiffness showed their maximum values and the void content was minimized at 0.1% EOGO. In addition, as the EOGO addition rate increased, the setting time tended to shorten, and the fluidity tended to decrease. This suggests that 0.1% EOGO is the most optimal content in metakaolin paste. This study confirms that EOGO is an additive material that can improve the performance of metakaolin-based geopolymers and presents opportunities for the development of sustainable construction materials through optimization of EOGO addition.