Fly ash-based geopolymers: The relationship between composition, pore structure and efflorescence

被引：392

作者：

Zhang, Zuhua ^{[1
]}

Provis, John L. ^{[2
]}

Reid, Andrew ^{[3
]}

Wang, Hao ^{[1
]}

机构：

[1] Univ So Queensland, Fac Hlth Engn & Sci, CEEFC, Toowoomba, Qld 4350, Australia

[2] Univ Sheffield, Dept Mat Sci & Engn, Sheffield S1 3JD, S Yorkshire, England

[3] Halok Engn Ltd, Brisbane, Qld 4101, Australia

来源：

CEMENT AND CONCRETE RESEARCH | 2014年 / 64卷

基金：

欧洲研究理事会; 澳大利亚研究理事会;

关键词：

Alkali activated cement; Fly ash; Carbonation; Durability; Pore size distribution; BLAST-FURNACE SLAG; BEHAVIOR;

D O I：

10.1016/j.cemconres.2014.06.004

中图分类号：

TU [建筑科学];

学科分类号：

0813 ;

摘要：

This study reports the observation of efflorescence in fly ash-based geopolymers. The efflorescence rate strongly depends on the activation conditions; at the same alkali content under ambient temperature curing, NaOH-activated geopolymers show less and slower efflorescence than sodium silicate-activated specimens. Geopolymers synthesised at high temperature exhibit much lower efflorescence than those synthesised at low temperature, except for the sodium silicate-activated samples. The substitution of 20% fly ash by slag reduces the efflorescence rate. A relationship between alkali leaching from monosized fractured particles and 'efflorescence potential' is proposed. Soluble silicate and slag addition are beneficial in reducing efflorescence rate, but have very limited influence on the overall efflorescence potential, as they appear to have a delaying rather than mitigating effect. The partial crystallisation of geopolymers, by curing at high temperature, appears to be the most effective method of reducing the efflorescence potential. (C) 2014 Elsevier Ltd. All rights reserved.

引用

页码：30 / 41

页数：12

共 44 条

[1] Changes in pore structure and mercury contact angle of hardened cement paste depending on relative humidity [J].

Adolphs, J ;

Setzer, MJ ;

Heine, P .

MATERIALS AND STRUCTURES, 2002, 35 (252) :477-486

[2]

[Anonymous], THESIS U SO QUEENSLA

[3] Resistance of geopolymer materials to acid attack [J].

Bakharev, T .

CEMENT AND CONCRETE RESEARCH, 2005, 35 (04) :658-670

[4] Influence of slag chemistry on the hydration of alkali-activated blast-furnace slag - Part II: Effect of Al2O3 [J].

Ben Haha, M. ;

Lothenbach, B. ;

Le Saout, G. ;

Winnefeld, F. .

CEMENT AND CONCRETE RESEARCH, 2012, 42 (01) :74-83

[5]

Bernal SA, 2014, Alkali activated materials, P223

[6]

Delair S, 2007, 12 INT C CHEM CEM

[7] Thermal conductivity of metakaolin geopolymers used as a first approximation for determining gel interconnectivity [J].

Duxson, Peter ;

Lukey, Grant C. ;

van Deventer, Jannie S. J. .

INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH, 2006, 45 (23) :7781-7788

[8] SODIUM CARBONATE-BICARBONATE MINERALS AS INDICATORS OF PCO2 [J].

EUGSTER, HP .

JOURNAL OF GEOPHYSICAL RESEARCH, 1966, 71 (14) :3369-&

[9] Effect of drying on cement-based materials pore structure as identified by mercury intrusion porosimetry -: A comparative study between oven-, vacuum-, and freeze-drying [J].

Gallé, C .

CEMENT AND CONCRETE RESEARCH, 2001, 31 (10) :1467-1477

[10] Modification of phase evolution in alkali-activated blast furnace slag by the incorporation of fly ash [J].

Ismail, Idawati ;

Bernal, Susan A. ;

Provis, John L. ;

Nicolas, Rackel San ;

Hamdan, Sinin ;

van Deventer, Jannie S. J. .

CEMENT & CONCRETE COMPOSITES, 2014, 45 :125-135

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