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Title: Efficacy of functionalized sodium-montmorillonite in mitigating alkali-silica reaction
Alkali-silica reaction (ASR) is a fatal deterioration that can cause volume expansion, cracking, and premature failure of concrete. In this study, the efficacy of sodium montmorillonite (NaMt) organically functionalized with two non-ionic surfactants (ONaMts) in mitigating ASR is investigated by determining the expansion and cracking behavior of mortars containing reactive aggregates. The underlying mitigation mechanisms were analyzed through the quantification of reaction products and in-situ characterizations of ASR gels. The results revealed that, compared with raw NaMt, ASR-induced expansion and cracking can be more substantially mitigated in the presence of ONaMts, which is supported by the improved consumption of portlandite and reduced formations of both crystalline and amorphous ASR gels. The functionalized ONaMts appeared to further suppress the formation of Q3 polymerization sites, decrease the [K + Na]/Si atomic ratio and increase the Al/Ca in ASR gels.  more » « less
Award ID(s):
1935799
NSF-PAR ID:
10482851
Author(s) / Creator(s):
;
Publisher / Repository:
Elsevier
Date Published:
Journal Name:
Applied Clay Science
Volume:
245
Issue:
C
ISSN:
0169-1317
Page Range / eLocation ID:
107139
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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