Microstructural and compositional change of NaOH-activated high calcium fly ash by incorporating Na-aluminate and co-existence of geopolymeric gel and C–S–H(I)

Handle URI:
http://hdl.handle.net/10754/598833
Title:
Microstructural and compositional change of NaOH-activated high calcium fly ash by incorporating Na-aluminate and co-existence of geopolymeric gel and C–S–H(I)
Authors:
Oh, Jae Eun; Moon, Juhyuk; Oh, Sang-Gyun; Clark, Simon M.; Monteiro, Paulo J.M.
Abstract:
This study explores the reaction products of alkali-activated Class C fly ash-based aluminosilicate samples by means of high-resolution synchrotron X-ray diffraction (HSXRD), scanning electron microscope (SEM), and compressive strength tests to investigate how the readily available aluminum affects the reaction. Class C fly ash-based aluminosilicate raw materials were prepared by incorporating Na-aluminate into the original fly ashes, then alkali-activated by 10 M NaOH solution. Incorporating Na-aluminate reduced the compressive strength of samples, with the reduction magnitude relatively constant regardless of length of curing period. The HSXRD provides evidence of the co-existence of C-S-H with geopolymeric gels and strongly suggests that the C-S-H formed in the current system is C-S-H(I). The back-scattered electron images suggest that the C-S-H(I) phase exists as small grains in a finely intermixed form with geopolymeric gels. Despite providing extra source of aluminum, adding Na-aluminate to the mixes did not decrease the Si/Al ratio of the geopolymeric gel. © 2012 Elsevier Ltd.
Citation:
Oh JE, Moon J, Oh S-G, Clark SM, Monteiro PJM (2012) Microstructural and compositional change of NaOH-activated high calcium fly ash by incorporating Na-aluminate and co-existence of geopolymeric gel and C–S–H(I). Cement and Concrete Research 42: 673–685. Available: http://dx.doi.org/10.1016/j.cemconres.2012.02.002.
Publisher:
Elsevier BV
Journal:
Cement and Concrete Research
KAUST Grant Number:
KUS-l1-004021
Issue Date:
May-2012
DOI:
10.1016/j.cemconres.2012.02.002
Type:
Article
ISSN:
0008-8846
Sponsors:
This publication was based on the work supported in part by Award no. KUS-l1-004021, made by King Abdullah University of Science and Technology (KAUST) and by NIST Grant no. 60NANB10D014. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract no. DE-AC02-05CH11231.
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Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorOh, Jae Eunen
dc.contributor.authorMoon, Juhyuken
dc.contributor.authorOh, Sang-Gyunen
dc.contributor.authorClark, Simon M.en
dc.contributor.authorMonteiro, Paulo J.M.en
dc.date.accessioned2016-02-25T13:42:06Zen
dc.date.available2016-02-25T13:42:06Zen
dc.date.issued2012-05en
dc.identifier.citationOh JE, Moon J, Oh S-G, Clark SM, Monteiro PJM (2012) Microstructural and compositional change of NaOH-activated high calcium fly ash by incorporating Na-aluminate and co-existence of geopolymeric gel and C–S–H(I). Cement and Concrete Research 42: 673–685. Available: http://dx.doi.org/10.1016/j.cemconres.2012.02.002.en
dc.identifier.issn0008-8846en
dc.identifier.doi10.1016/j.cemconres.2012.02.002en
dc.identifier.urihttp://hdl.handle.net/10754/598833en
dc.description.abstractThis study explores the reaction products of alkali-activated Class C fly ash-based aluminosilicate samples by means of high-resolution synchrotron X-ray diffraction (HSXRD), scanning electron microscope (SEM), and compressive strength tests to investigate how the readily available aluminum affects the reaction. Class C fly ash-based aluminosilicate raw materials were prepared by incorporating Na-aluminate into the original fly ashes, then alkali-activated by 10 M NaOH solution. Incorporating Na-aluminate reduced the compressive strength of samples, with the reduction magnitude relatively constant regardless of length of curing period. The HSXRD provides evidence of the co-existence of C-S-H with geopolymeric gels and strongly suggests that the C-S-H formed in the current system is C-S-H(I). The back-scattered electron images suggest that the C-S-H(I) phase exists as small grains in a finely intermixed form with geopolymeric gels. Despite providing extra source of aluminum, adding Na-aluminate to the mixes did not decrease the Si/Al ratio of the geopolymeric gel. © 2012 Elsevier Ltd.en
dc.description.sponsorshipThis publication was based on the work supported in part by Award no. KUS-l1-004021, made by King Abdullah University of Science and Technology (KAUST) and by NIST Grant no. 60NANB10D014. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract no. DE-AC02-05CH11231.en
dc.publisherElsevier BVen
dc.subjectAlkali activated cement (D)en
dc.subjectC-S-H (B)en
dc.subjectFly ash (D)en
dc.subjectGeopolymeren
dc.subjectX-ray diffraction (B)en
dc.titleMicrostructural and compositional change of NaOH-activated high calcium fly ash by incorporating Na-aluminate and co-existence of geopolymeric gel and C–S–H(I)en
dc.typeArticleen
dc.identifier.journalCement and Concrete Researchen
dc.contributor.institutionUC Berkeley, Berkeley, United Statesen
dc.contributor.institutionUlsan National Institute of Science and Technology, Ulsan, South Koreaen
dc.contributor.institutionDong Eui University, Busan, South Koreaen
dc.contributor.institutionLawrence Berkeley National Laboratory, Berkeley, United Statesen
dc.contributor.institutionMacquarie University, North Ryde, Australiaen
kaust.grant.numberKUS-l1-004021en
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