Impact of crushing shape and geopolymerization on reclaimed concrete aggregate for recycling in the flexible pavement: an enhanced circular economy solution

Sattar, Omer; Khalid, Usama; Rehman, Zia ur; Kayani, Wasim Irshad; Haider, Abbas

doi:10.1080/14680629.2023.2287711

Cited by 2 publications

(1 citation statement)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The alkali-activated binder consists of an alkali activator, precursors and auxiliary materials. Precursor particles, mainly calcined natural minerals (e.g., metakaolin (MK)) or industrial solid wastes (e.g., granulated blast furnace slag (GBFS) and fly ash (FA)), contain reactive silica-alumina oxides that can be stimulated by alkali activators to produce C-S-H and C(N)-A-S-H gels through a series of dissolution-diffusion-polymerization reactions [13,14]. These gels are able to connect the soil particles and fill the pores to improve the microstructure of SC, thus improving the properties of SC [13,15].…”

Section: Introductionmentioning

confidence: 99%

The Design of a Novel Alkali-Activated Binder for Solidifying Silty Soft Clay and the Study of Its Solidification Mechanism

Jing,

Zhang,

Zhang

et al. 2024

Materials

View full text Add to dashboard Cite

In order to overcome the problems of the high economic and environmental costs of a traditional ordinary portland cement-based binder, this study used self-combusted coal gangue (SCCG), granulated blast furnace slag (GBFS) and phosphorous slag (PS) to prepare a novel SCCG-GBFS-PS (SGP) ternary alkali-activated binder for solidifying silty soft clay (SC). Firstly, the parameters of the SGP ternary binder were optimized using orthogonal experiments. Then the effects of the SGP ternary binder content (mass ratio of the SGP ternary binder and the SGP-solidified soil), initial water content of SC (mass ratio of SC’ water and SC) and types of additives on the unconfined compressive strength (UCS) of the SGP-solidified soil were analyzed. Finally, the hydration products and microstructure of the SGP-solidified soil were analyzed to investigate the solidification mechanism of the SGP ternary binder. The results showed that the optimal mass ratio of GBFS and PS is 2:1, and the optimal alkali activator content (mass ratio of Na2O and the SGP ternary binder) and modulus of alkali activator (molar ratio of SiO2 and Na2O of alkali activator) were 13% and 1.3, respectively. When the SGP ternary binder content was 16% and the initial water content of SC was 35%, the SGP-solidified soil met the requirement of UCS for tertiary cured soil. The incorporation of triethanolamine and polyvinyl alcohol improved the UCS, while the incorporation of Na2SO4 significantly deteriorated the UCS of the SGP-solidified soil. The C-S-H gels and C(N)-A-S-H gels generated by hydration of the SGP-solidified soil were interspersed, interwoven and adhered to each other to form a network-like space structure that played the roles of skeleton, bonding soil particles and filling pores, which improved the macroscopic properties of the SGP-solidified soil. The results of this study provide a reference for the design and development of a solid waste-based binder for solidifying SC.

show abstract