Effect of source and particle size distribution on the mechanical and microstructural properties of fly Ash-Based geopolymer concrete

Assi, Lateef; Deaver, Edward; Ziehl, Paul

doi:10.1016/j.conbuildmat.2018.01.193

Cited by 161 publications

(58 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…We used the grain size analysis to identify the grinding status of the studied wastes which is fine or course in order to keep the homogeneity of the mixes and to prevent presence of voids or cracks within the geopolymer mortar. Moreover, the compressive strength of geopolymer mortar relatively decreases with high grain size [27]. The chemical composition was obtained by XRF and the crystalline phases by XRD.…”

Section: Methodsmentioning

confidence: 99%

Immobilization of Some Heavy Metals in Geopolymer Based on Water Treatment Sludge and Alum Industry Solid Waste

Abdelaal

Abdelmawla

Beheary

et al. 2020

Alfarama Journal of Basic & Applied Sciences

View full text Add to dashboard Cite

This paper investigates the immobilization behaviors of Cd 2+ , Pb 2+ and Hg 2+ ions in a geopolymer based on water treatment sludge (WTS) and dealuminated metakaolin (DaMK) solid waste from alum industry. For synthesis of WTS/DaMK based geopolymer, five mixes of WTS/DaMK (75/25, 80/20, 85/15, 90/10 and 95/5, respectively) are tested to obtain the optimum synthesis condition based on the compressive strength. Results showed that the geopolymer mortar with 85/15WTS/DaMK has the highest compressive strength (8 MPa). In addition, X-ray Diffraction (XRD) and X-ray Fluorescence (XRF) techniques are used to characterize the mineral and chemical compositions of WTS and DaMK. WTS/DaMK based geopolymer mortar have been tested for leaching to study its immobilization behavior under the optimum condition. The Cd 2+ , Pb 2+ and Hg 2+ ions were used and effectively immobilized in this study. The heavy metals with concentrations of 100, 200 and 300 ppm were used in the geopolymer matrix giving about 98% of immobilization efficiency. The study showed that Pb 2+ has the best immobilization efficiency followed by Hg 2+ and Cd 2+ with high concentrations.

show abstract

Section: Methodsmentioning

confidence: 99%

Immobilization of Some Heavy Metals in Geopolymer Based on Water Treatment Sludge and Alum Industry Solid Waste

Abdelaal

Abdelmawla

Beheary

et al. 2020

Alfarama Journal of Basic & Applied Sciences

View full text Add to dashboard Cite

show abstract

“…Geopolymer concrete gains strength with time when cured at ambient conditions [47]. Likewise, the water absorption of geopolymer concrete depends on the type of aluminosilicate source and particle size [48]. The effects of different dosages of SCBA aluminosilicate in geopolymer concrete still needs to be studied.…”

Section: Water Absorption Testmentioning

confidence: 99%

Experimental Investigation of NaOH and KOH Mixture in SCBA-Based Geopolymer Cement Composite

et al. 2020

View full text Add to dashboard Cite

This research aimed at exploring the effects of a mixture of sodium hydroxide (NaOH) and potassium hydroxide (KOH) activators in a sugar cane bagasse ash (SCBA)-based geopolymer cement paste. Bagasse ash replacement was 20% of cement by weight. The mixture of NaOH and KOH comprised 4, 8, and 12 M solutions with mixing percentages of 0%, 20%, 40%, 60%, 80%, and 100% for all possible combinations. A pH test was performed on each possible combination of solutions. A Chapelle’s test, XRD, X-ray fluorescence (XRF), and SEM analysis were used to check whether the SCBA exhibited pozzolanic reactivity. Subsequently, the SCBA geopolymer cement paste was tested for compressive strength, water absorption, permeable porosity, and sorptivity. It was estimated that the geopolymer cement paste exhibited higher absorption and sorptivity values than control mixtures when molarity increased. However, the samples prepared with combinations of the 8 M activator solution exhibited consistent absorption, sorptivity, and compressive strength values when compared to the control and other geopolymer mixtures with 4 and 12 M activator solutions. Thus, the two activator solutions G8N408K60 and G8N208K80—where GxNayKb represents the geopolymer concrete sample prepared by adding solutions of two bases, i.e., ‘xNayKb’ showing an ‘a’ percentage of ‘x’ molar NaOH and a ‘b’ percentage of ‘y’ molar KOH—were obtained as the optimum molar ratio of the activator in geopolymer concrete. The geopolymer cement pastes, along with the optimum and control samples, were further tested for concrete durability, SEM, and TGA tests. The G8N208K80 sample exhibited a better mechanical and durability performance than the G8N408K60 sample. The durability performance of the geopolymer concrete was also superior to ordinary concrete. Moreover, the geopolymer concrete achieved a 21% reduction in global warming potential compared to the control mixture. Thus, it can be concluded that the use of SCBA ash in geopolymer concrete can address the ash disposal and CO2 emission problems with enhanced durability.

show abstract

“…Smaller particle size means larger surface area. L.N Assi et al [8] found that smaller particle size lead to denser microstructure and enhance geopolymerization process. Larger surface area also increase the need of water, which can reduced the microcrack formation as less water available to evaporate.…”

Section: Particle Size Distributionmentioning

confidence: 99%

Characterization and Comparison of Geopolymer Synthesized Using Metakaolin Bangka and Metastar as Precursors

2018

View full text Add to dashboard Cite

Various aluminosilicate material have been used as precursor for geopolymer. Geopolymer gets its strength from the polycondensation of silicate and alumina. Metakaolin, calcinated kaolin, is pozzolan with the highest alumina and silicate purity. Indonesia, especially Bangka Island, has a large amount of kaolin deposit that being sold at low price. This price could be increased ten times when being sold as metakaolin. This study aimed to compare mechanical and metallurgical properties of commercial metakaolin and Bangka kaolin which calcinated at 700°C. Both metakaolins reacted with NaOH and waterglass as the activator followed by curing at room temperature for 7, 14 and 28 days and elevated temperature of 60°C for 4, 12 and 24 hours. Mechanical properties will be examined by compressive strength and flexural strength test, while the metallurgical properties will be evaluated with SEM, and TAM. The results of the mechanical test will be used to determine which geopolymer will perform well with the microstructure and thermal activity to support the finding. These attempts will be done in order to improve the properties of Bangka metakaolin geopolymer superior to commercial metakaolin.

show abstract

Effect of source and particle size distribution on the mechanical and microstructural properties of fly Ash-Based geopolymer concrete

Cited by 161 publications

References 15 publications

Immobilization of Some Heavy Metals in Geopolymer Based on Water Treatment Sludge and Alum Industry Solid Waste

Immobilization of Some Heavy Metals in Geopolymer Based on Water Treatment Sludge and Alum Industry Solid Waste

Experimental Investigation of NaOH and KOH Mixture in SCBA-Based Geopolymer Cement Composite

Characterization and Comparison of Geopolymer Synthesized Using Metakaolin Bangka and Metastar as Precursors

Contact Info

Product

Resources

About