Effect of slag, silica fume, and metakaolin on properties and performance of alkali-activated fly ash cured at ambient temperature

Alanazi, Hani; Hu, Jiong; Kim, Yong-Rak

doi:10.1016/j.conbuildmat.2018.11.172

Cited by 133 publications

(33 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Therefore, the UCS was higher in the SF5 group than in the SF0 group. With an increase in the amount of silica fume, UCS showed a trend of increasing first and then decreasing, which is similar to the experimental results of silica fume mixed with concrete presented by Wetzel et al [41] and Alanazi et al [42]. It is worth noting that for the SF15 and SF20 groups, the UCS value of all curing ages was significantly lower than that of SF0, which indicates that the more silica fume that is used, the easier it is to decrease the UCS.…”

Section: Unconfined Compressive Strengthsupporting

confidence: 89%

Preparation of a New Type of Cemented Paste Backfill with an Alkali-Activated Silica Fume and Slag Composite Binder

Sun

2020

Materials

View full text Add to dashboard Cite

A new type of cemented paste backfill (CPB) was prepared using sodium hydroxide (NaOH) as the activator, slag and silica fume (SF) as the binder, and tailings as the aggregate. The effects of proportion of replacement of 0%, 5%, 10%, 15%, and 20% silica fume on the properties of CPB were studied. The strength formation mechanism of CPB was explored through a combination of scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and Fourier transform infrared (FTIR) spectroscopy. The SEM images were analyzed by IMAGE J software, and the porosity of CPB with different silica fume contents was obtained. The results show that as the amount of silica fume increases, the unconfined compressive strength (UCS) increases first and then decreases. When the amount of silica fume was approximately 5%, CPB with a larger UCS can be obtained. When the silica fume content increased from 0% to 5%, because silica fume has good activity and small particles, more calcium silicate hydrate (C–S–H) gels and Mg-Al type layered double hydrotalcites (LDHs) were generated in CPB, which made it denser and improved its strength compared with the non-silica fume group. C–S–H gels were the main source of CPB strength. With a further increase in the amount of silica fume, thaumasite produced inside of CPB, reducing the content of C–S–H gels. Moreover, due to the expansion of thaumasite, it is easy to generate a large number of micro cracks in CPB, which weakens the strength of CPB.

show abstract

Section: Unconfined Compressive Strengthsupporting

confidence: 89%

Preparation of a New Type of Cemented Paste Backfill with an Alkali-Activated Silica Fume and Slag Composite Binder

Sun

2020

Materials

View full text Add to dashboard Cite

show abstract

“…In most scenarios, this would eliminate the need for elevated temperature curing and could facilitate industrial implementations. For instance, the addition of slag to alkali activated fly ash was investigated [60]. In addition to room temperature curing, two fly ash samples were also cured at 60 • C. The latter showed higher UCS compared to same samples cured at ambient temperature.…”

Section: Ground Granulated Blast Furnace Slagmentioning

confidence: 99%

Quarry Waste as Precursors in Geopolymers for Civil Engineering Applications: A Decade in Review

Solouki

Viscomi²,

Lamperti³

et al. 2020

Materials

View full text Add to dashboard Cite

Carbon footprint reduction of paving materials could be explored through recycling mining by-products into different applications, which will preserve natural resources and decrease environmental issues. One possible approach is to reuse quarry dust and mining ore waste as precursors in geopolymer applications. geopolymers are mineral polymers rich in aluminosilicates with an amorphous to a semi-crystalline three-dimensional structure. The current review aims to summarize the studies conducted during the past decade on geopolymers containing quarry dust and mine tailings. The first section discusses various precursors used for geopolymer cement production such as metakaolin, ground granulated blast furnace slag (GGBFS), fly ash, and quarry/mining ore wastes including silt, tungsten, vanadium, copper, gold, zinc, marble, iron, basalt, and lithium. Different calcination treatments and curing conditions have been summarized. In some cases, the precursors are required to be calcined to increase their reactivity. Both ambient temperature and elevated temperature curing conditions have been summarized. Less attention has been paid to room temperature curing, which is necessary for field and industrial implementations. Engineering properties such as compressive strength, density, durability and acid resistance, water absorption and abrasion of geopolymers containing mining waste were reviewed. One of the main barriers preventing the widespread use of waste powders, in addition to economic aspects, in geopolymers could be due to their unstable chemical structure. This was shown through extensive leachate of Na+ or K+ cations in geopolymer structures. The review of over 100 articles indicated the need for further research on different aspects of quarry waste geopolymer productions before its full industrial implementation.

show abstract

“…On the other hand, because of its advantages like good thermal insulation, light weight, and low cost [4,5], FLA has been widely used in some architectural elds like nonbearing wall construction, bathroom back lling and as functional materials such as thermal insulation material, sound-insulation material, and so on [6,7]. Apart from being used in the traditional building elds, FLA has been applied in di erent areas as a good raw material for the preparation of geopolymer [8][9][10][11][12]. For example, to prove the possibility of in-situ resource utilization of FLA, there are a good many scholars having done plenty of basic studies on this aspect [13][14][15], among which there is one proposing that y ash foamed geopolymer (FAFG) as back lling material can be an excellent combination of y ash consumption and coal mine re prevention [16,17].…”

Section: Introductionmentioning

confidence: 99%

Fly Ash Particle Size Effect on Pore Structure and Strength of Fly Ash Foamed Geopolymer

Xiong

Wan

Zhou

et al. 2019

Advances in Polymer Technology

View full text Add to dashboard Cite

e aim of this paper is to study the particle size e ect of y ash (FLA) on pore structure and strength of Fly Ash Foamed Geopolymer (FAFG). Information on the macro-pores such as macro-pore size and distribution of FAFG is captured through binarization processing. Porosity and compressive strength of FAFG are respectively tested by Archimedes density test method and uniaxial compressive strength test method. It can be concluded that the FLA particle size has an e ect on the pore structure and strength of FAFG. More speci cally, the e ect of FLA particle size shows itself macroscopically on the quantity of middle and large macro-pores and the uniformity of macro-pores distribution, and microscopically on the quantity of micro-holes and cracks and calcium silicate (C-S-H) quantity at the early stage of FAFG mixture. All of the properties of FAFG follow some kind of changing rule except at the turning point when FLA particle is of 0.125~0.25 mm in size. To explain clearly the root cause of FLA particle size e ect on FAFG, SEM, and XRD are employed to explore the microstructure of FAFG and the component of FLA. It turns out to be the amorphous phase SiO 2 content in FLA of di erent particle sizes which could determine the reaction extent of FAFG mixture.

show abstract

Effect of slag, silica fume, and metakaolin on properties and performance of alkali-activated fly ash cured at ambient temperature

Cited by 133 publications

References 36 publications

Preparation of a New Type of Cemented Paste Backfill with an Alkali-Activated Silica Fume and Slag Composite Binder

Preparation of a New Type of Cemented Paste Backfill with an Alkali-Activated Silica Fume and Slag Composite Binder

Quarry Waste as Precursors in Geopolymers for Civil Engineering Applications: A Decade in Review

Fly Ash Particle Size Effect on Pore Structure and Strength of Fly Ash Foamed Geopolymer

Contact Info

Product

Resources

About