## 1 Introduction  
The construction industry is highly concerned about its contribution to global warming, resulting from the carbon emissions (CO\({}_{2}\)) associated with its activities. The primary sources of CO\({}_{2}\) emission in the construction industry are materials production, construction activities, transportation, and waste generation. Portland cement (PC) is one of the major contributors of CO\({}_{2}\) in the industry. This emission emanates from the combustion of carbon-based fuel and the thermal decomposition of limestone in the rotary kiln to produce calcium oxide [1]. The production of 1 kg of PC produces almost an equivalent quantity (0.8-0.9 kg) of CO\({}_{2}\)[2; 3; 4]. Additional studies have determined that PC manufacturing accounts for approximately 7% of the worldwide CO\({}_{2}\) emissions [5; 6; 7]. Furthermore, an estimated 1.45 \(\pm\) 0.29 gigatomes (Gt) of global CO\({}_{2}\) emissions were attributed to cement production in 2016, according to [PERSON] [8]. This contributed to a cumulative total of 39.3 Gt of CO\({}_{2}\) emissions from 1928 to 2016. In 1979, [PERSON] introduced a novel geopolymer binder produced with calcium- and silicate-rich precursors. Geopolymer binders are formed through a chemical reaction between aluminosilicate materials and alkalis (reagents), resulting in a hardened matrix [9]. This binder is formed by subjecting the precursors to alkalinisation, which depolymerises the silicates (depolymerisation of silicates) and leads to the gel formation of oligo-salates. The oligosialates polycondense rearranges to form a network structure and solidify into a hardened geopolymer. This innovative process bypasses the carbon-intensive production of PCs and offers potential environmental benefits. However, the first invented geopolymer binder, known as two-part, is less user and environmentally friendly due to the use of liquid alkali reagents that are corrosive, viscous, and hygroscopic in nature. Consequently, a one-part geopolymer binder was developed, a user- and environmentally-friendly alternative that mitigates the limitations of a two-part geopolymer binder, particularly in mass in-situ concrete production. Contrary to two-part geopolymer, one-part geopolymer binder requires dry-mixing (similar to conventional binder) of the aluminosilicate precursors with solid reagents before water is then added to promote the dissolution, reorganisation, and polymerisation of the mixture [10]. A one-part geopolymer binder has been found to have a global warming potential that is 22% lower than a two-part geopolymer binder and 65% lower than PC, mainly due to the reduction or substitution of NaOH [7]. Hence, a one-part geopolymer is environmentally friendly compared to a two-part and conventional binder. However, the mix design is challenging and laborious due to the need for exquisite selection and proportion of raw materials, curing method, and the use of effective admixtures to achieve the required workability, setting time, strength, and durability properties. Available studies on one-part geopolymer concrete are mostly focused on fly ash (FA)-based one-part geopolymer binder or concrete, with limited information on metakaolin (MK)-based one-part geopolymer concrete. MK is a precursor that offers a higher degree of purity in terms of aluminosilicate compared to FA. It is produced by subjecting kaolin to dehydroxylation within a temperature range of 650 \({}^{\circ}\)C to 800 \({}^{\circ}\)C [11; 12]. MK consists of a significant amount, approximately 55% of SiO\({}_{2}\) and Al\({}_{2}\)O\({}_{3}\), along with small quantities of other minerals, such as Fe\({}_{2}\)O\({}_{3}\) and TiO\({}_{2}\)[13; 14]. Still, it lacks calcium oxide, which is the hydration phase of cement. Its primary source (Kaolin) is the most abundant aluminosilicate precursor on earth, with over 5 billion tonnes available [14].