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Title: Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis

Abstract

Structural properties associated with alkali-silica reaction were systematically investigated by means of macro-structural accelerated mortar prism expansion levels testing, combined with micro-structural analysis. One part of this study is to determine the reactivity of the aggregate by means of accelerated mortar bar tests, and also to evaluate perlite aggregate constituents, especially the presence of deleterious components and find main causes of the alkali-silica reaction, which was based on the petrographic studies by optical microscope and the implication of X-ray diffraction on the aggregate. Results implied that the aggregate was highly alkali-silica reactive and the main micro-crystalline quartz-intermediate character and matrix that is mainly composed of chalcedony are potentially suitable for alkali-silica reaction. The other part is to study the long-term effect of lithium salts against alkali-silica reaction by testing accelerated mortar prism expansion levels. The macro-structural results were also consistent with the micro-structural mechanisms of alkali-silica reaction of mortar prisms containing this aggregate and the effect of chemical admixtures by means of the methods of scanning electron microscope-X-ray energy-dispersive spectroscopy and X-ray diffraction. It was indicated by these techniques that lithium salts, which were introduced into concrete containing reactive aggregate at the mixing stage, suppressed the alkali-silica reaction by producingmore » non-expansive crystalline materials.« less

Authors:
 [1];  [2]
  1. Nanjing Normal University, Analysis and Testing Center and Materials Science Key Laboratory, Nanjing 210097, Jiangsu Province (China). E-mail: moxiangyin@njnu.edu.cn
  2. Natural Resources Canada, Materials Technology Laboratory, CANMET, Ottawa, Ontario, K1A 0G1 (Canada)
Publication Date:
OSTI Identifier:
21003532
Resource Type:
Journal Article
Resource Relation:
Journal Name: Materials Characterization; Journal Volume: 58; Journal Issue: 2; Other Information: DOI: 10.1016/j.matchar.2006.04.018; PII: S1044-5803(06)00115-X; Copyright (c) 2006 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CONCRETES; EXPANSION; LITHIUM; LITHIUM COMPOUNDS; MATERIALS TESTING; OPTICAL MICROSCOPES; PERLITE; PRISMS; QUARTZ; REACTIVITY; SALTS; SCANNING ELECTRON MICROSCOPY; SILICA; SPECTROSCOPY; X-RAY DIFFRACTION

Citation Formats

Mo Xiangyin, and Fournier, Benoit. Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis. United States: N. p., 2007. Web.
Mo Xiangyin, & Fournier, Benoit. Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis. United States.
Mo Xiangyin, and Fournier, Benoit. Thu . "Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis". United States. doi:.
@article{osti_21003532,
title = {Investigation of structural properties associated with alkali-silica reaction by means of macro- and micro-structural analysis},
author = {Mo Xiangyin and Fournier, Benoit},
abstractNote = {Structural properties associated with alkali-silica reaction were systematically investigated by means of macro-structural accelerated mortar prism expansion levels testing, combined with micro-structural analysis. One part of this study is to determine the reactivity of the aggregate by means of accelerated mortar bar tests, and also to evaluate perlite aggregate constituents, especially the presence of deleterious components and find main causes of the alkali-silica reaction, which was based on the petrographic studies by optical microscope and the implication of X-ray diffraction on the aggregate. Results implied that the aggregate was highly alkali-silica reactive and the main micro-crystalline quartz-intermediate character and matrix that is mainly composed of chalcedony are potentially suitable for alkali-silica reaction. The other part is to study the long-term effect of lithium salts against alkali-silica reaction by testing accelerated mortar prism expansion levels. The macro-structural results were also consistent with the micro-structural mechanisms of alkali-silica reaction of mortar prisms containing this aggregate and the effect of chemical admixtures by means of the methods of scanning electron microscope-X-ray energy-dispersive spectroscopy and X-ray diffraction. It was indicated by these techniques that lithium salts, which were introduced into concrete containing reactive aggregate at the mixing stage, suppressed the alkali-silica reaction by producing non-expansive crystalline materials.},
doi = {},
journal = {Materials Characterization},
number = 2,
volume = 58,
place = {United States},
year = {Thu Feb 15 00:00:00 EST 2007},
month = {Thu Feb 15 00:00:00 EST 2007}
}
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