Alkali-activated fly ash/slag cements: Strength behaviour and hydration products

TL;DR: In this paper, an experimental study on geopolymer synthesized with class F fly ash (FA) and low-calcium slag (SG) was carried out using FA and SG at different rela...

TL;DR: In this paper, the results of a study on the early hydration process of pastes composed of ground granulated blast furnace slag and fly ash from fluidized bed combustion of brown coal are presented.

Abstract: Abstract The addition of phase change materials (PCM) to geo polymer mortar (GPM) is a promising advance in the pursuit of ecologically benign and energy‐efficient construction materials. This review looks at the synthesis, characterization, and performance of GPMs, with a particular emphasis on the consequences of adding PCMs. The review emphasizes the growing global demand for energy‐efficient construction solutions and discusses the critical role of geo polymer mortar in meeting this demand. It also addresses the synergy between PCM and GPM, revealing the principles underlying PCM's latent heat storage capacities and the geo polymer's ability to operate as a stable and durable matrix. Major findings show that PCMs considerably improve the thermal characteristics of GPMs by increasing heat capacity and decreasing thermal conductivity. In addition to boosting durability and thermal resilience, the energy‐storing PCM and the strong GPM combo increase long‐term performance. The PCM incorporated GPM improves thermal energy storage capacities; energy savings of up to 30% for cooling and 15% for heating. However, the addition of PCMs often results in a minor drop in mechanical performance, particularly compressive strength. Although the mortar is weak due to the development of air spaces and weak connections between the PCM capsules and the mortar matrix the strengths are within acceptable limits. Future study is needed to improve long‐term performance and endurance in demanding real‐world environments. This comprehensive review will inspire further research, innovation, and adoption of this technology, thereby contributing to a greener and more energy‐efficient built environment.

TL;DR: Alkali-activated cements as discussed by the authors are those with compositions falling in the Me2O-MeO-me2O3-SiO2-H2O system, and their history of development and present status are reviewed.

TL;DR: In this paper, the joint influence of a series of factors (specific surface of slag, curing temperature, activator concentration, and the nature of the alkaline activator) on the development of mechanical strengths in alkaline-activated slag cement mortars was investigated.

TL;DR: In this paper, the authors summarized the advantageous and disadvantageous properties of alkali-activated slag cement and concrete by reviewing previously published work in English, Russian and Chinese, and discussed practical problems and theoretical questions concerning alkaline activation.

TL;DR: In this paper, the authors examined the early hydration of alkali-slag cements activated by different sodium compounds, such as NaOH, NaCO3, Na2SiO3 and NaF, at 25 and 50 °C.