Structural alterations in alkali-sulfate-activated slag cement pastes induced by natural and accelerated carbonation

IF 10.9 1区 工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY
{"title":"Structural alterations in alkali-sulfate-activated slag cement pastes induced by natural and accelerated carbonation","authors":"","doi":"10.1016/j.cemconres.2024.107713","DOIUrl":null,"url":null,"abstract":"<div><div>The impact of carbonation, induced at different CO<sub>2</sub> concentrations (0.04 or 1 %), in the phase assemblages and compressive strength of Na<sub>2</sub>SO<sub>4</sub>-activated slag materials was determined. Carbonation led to Ca-bearing phases' decalcification (mainly C-(A)-S-H type gel and ettringite) forming different CaCO<sub>3</sub> polymorphs, independent of the slag composition or carbonation conditions adopted. In specimens exposed to 0.04 % CO<sub>2</sub>, a negligible carbonation front was observed, along with a continued phase assemblage evolution and compressive strength gain after 500 days of exposure. Conversely, exposure to 1 % CO<sub>2</sub> led to complete carbonation after 28 days, and a significant compressive strength reduction. Accelerated carbonation does not lead to the development of comparable microstructures to those observed in naturally carbonated pastes. The accelerated carbonation rates were ~ 33 times higher than those determined under natural carbonation exposure. Therefore, accelerated tests are considered unsuitable for predicting the long-term carbonation performance of Na<sub>2</sub>SO<sub>4</sub>-activated slag cements.</div></div>","PeriodicalId":266,"journal":{"name":"Cement and Concrete Research","volume":null,"pages":null},"PeriodicalIF":10.9000,"publicationDate":"2024-11-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Cement and Concrete Research","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0008884624002941","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

The impact of carbonation, induced at different CO2 concentrations (0.04 or 1 %), in the phase assemblages and compressive strength of Na2SO4-activated slag materials was determined. Carbonation led to Ca-bearing phases' decalcification (mainly C-(A)-S-H type gel and ettringite) forming different CaCO3 polymorphs, independent of the slag composition or carbonation conditions adopted. In specimens exposed to 0.04 % CO2, a negligible carbonation front was observed, along with a continued phase assemblage evolution and compressive strength gain after 500 days of exposure. Conversely, exposure to 1 % CO2 led to complete carbonation after 28 days, and a significant compressive strength reduction. Accelerated carbonation does not lead to the development of comparable microstructures to those observed in naturally carbonated pastes. The accelerated carbonation rates were ~ 33 times higher than those determined under natural carbonation exposure. Therefore, accelerated tests are considered unsuitable for predicting the long-term carbonation performance of Na2SO4-activated slag cements.
自然碳化和加速碳化引起的碱硫酸盐活性矿渣水泥浆的结构变化
研究确定了不同二氧化碳浓度(0.04 或 1%)下碳化对 Na2SO4 活性矿渣材料的相组合和抗压强度的影响。碳化导致了含钙相的脱钙(主要是 C-(A)-S-H 型凝胶和埃特林特),形成了不同的 CaCO3 多晶体,这与所采用的炉渣成分或碳化条件无关。在暴露于 0.04 % CO2 的试样中,碳化前沿可忽略不计,同时在暴露 500 天后,相组合继续演变,抗压强度增加。相反,暴露于 1 % CO2 的试样在 28 天后完全碳化,抗压强度显著降低。加速碳化并不会导致形成与自然碳化浆料中观察到的相似的微观结构。加速碳化率比自然碳化条件下测定的碳化率高出约 33 倍。因此,我们认为加速试验不适合用来预测 Na2SO4 活性矿渣水泥的长期碳化性能。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Cement and Concrete Research
Cement and Concrete Research 工程技术-材料科学:综合
CiteScore
20.90
自引率
12.30%
发文量
318
审稿时长
53 days
期刊介绍: Cement and Concrete Research is dedicated to publishing top-notch research on the materials science and engineering of cement, cement composites, mortars, concrete, and related materials incorporating cement or other mineral binders. The journal prioritizes reporting significant findings in research on the properties and performance of cementitious materials. It also covers novel experimental techniques, the latest analytical and modeling methods, examination and diagnosis of actual cement and concrete structures, and the exploration of potential improvements in materials.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信