Effect of Corrosive Solutions on C-S-H Microstructure in Portland Cement Paste with Fly Ash

被引：5

作者：

丁庆军 ^{[1
]}

WANG Huan ^{[1
]}

HU Chenguang ^{[2
]}

张高展 ^{[1
,3
]}

机构：

[1] School of Materials Science and Engineering, Wuhan University of Technology

[2] College of Materials Science and Engineering, North China University of Science and Technology

[3] School of Materials and Chemical Engineering, Anhui Jianzhu University

来源：

Journal of Wuhan University of Technology(Materials Science) | 2016年 / 31卷 / 05期

关键词：

corrosive solutions; cement; fly ash; C-S-H microstructure; Al[4]/Si;

D O I：

暂无

中图分类号：

TU52 [非金属材料]; TQ172.1 [基础理论];

学科分类号：

0805 ; 080502 ; 081304 ;

摘要：

By means of 29Si and 27Al magic angle spinning nuclear magnetic resonance（MAS NMR） combined with deconvolution technique, X-ray diffraction（XRD）, scanning electron microscopy（SEM） as well as energy dispersive X-ray system（EDX）, the effect of 5 wt% corrosive solutions( viz. 5 wt% Na2SO4, MgSO4, Na2SO_4+Na Cl and Na2SO_4+Na Cl+Na2CO3) on C-S-H microstructure in portland cement containing 30 wt% fly ash was investigated.The results show that, in MgSO4 solution, Mg2+ promotes the decalcification of C-S-H by SO42-,increasing silicate tetrahedra polymerization and mean chain length（MCL） of C-S-H. However, the substituting degree of Al3+ for Si4+（Al[4]/Si） in the paste does not change evidently. Effect of Na2SO4 solution on C-S-H is not significantly influenced by Na Cl solution, while the MCL and Al[4]/Si of C-S-H in fly ashcement paste slightly change. However, the decalcification of C-S-H by SO42- and CO32- attack, as well as the activation of fly ash by SO42- attack will increase the MCL and Al[4]/Si, which are both higher than that under Na2SO4 corrosion, MgSO4 or Na2SO4 +Na Cl coordination corrosion.

引用

页码：1002 / 1007

页数：6

共 9 条

[1] 29Si固体核磁共振技术在水泥化学研究中的应用 [J].

何永佳 ;

胡曙光 .

材料科学与工程学报, 2007, (01) :147-153

[2]

New procedure to investigate external sulphate attack on cementitious materials[J] . R. El-Hachem,E. Rozière,F. Grondin,A. Loukili. Cement and Concrete Composites . 2011 (3)

[3]

Effect on fresh C-S-H gels of the simultaneous addition of alkali and aluminium[J] . I. García Lodeiro,A. Fernández-Jimenez,A. Palomo,D.E Macphee. Cement and Concrete Research . 2009 (1)

[4]

The role played by the reactive alumina content in the alkaline activation of fly ashes[J] . A. Fernández-Jiménez,A. Palomo,I. Sobrados,J. Sanz. Microporous and Mesoporous Materials . 2005 (1)

[5]

Tobermorite/jennite- and tobermorite/calcium hydroxide-based models for the structure of C-S-H: applicability to hardened pastes of tricalcium silicate, β-dicalcium silicate, Portland cement, and blends of Portland cement with blast-furnace slag, metakaolin, or silica fume[J] . I.G. Richardson. Cement and Concrete Research . 2004 (9)

[6]

Microstructural study of sulfate attack on ordinary and limestone Portland cements at ambient temperature[J] . E.F Irassar,V.L Bonavetti,M González. Cement and Concrete Research . 2002 (1)

[7] The nature of C-S-H in hardened cements [J].

Richardson, IG .

CEMENT AND CONCRETE RESEARCH, 1999, 29 (08) :1131-1147

[8]

Cement Chemistry .2 Taylor H F W. London . 1997

[9]

Application of NMR Spectroscopy to Cement Science .2 Grimmer AR. London . 1994

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