Adsorption of Naphthalene-Based Water Reducer on Alkali-Activated Slag Cement

In this work, the adsorption of naphthalene-based water reducer (FDN) on slag ground with or without the composite retarder YP-3 and PN (YP) in alkali-activated slag cement (AASC) activated by water glass (WG) has been studied in detail. The results show that the effect of the adsorption of water reducer on AASC depends directly on the dosage of the water reducer and on the composite retarder used. For example, mixed slag particles adsorb thrice as much water reducer FDN than pure slag particles at 1% mass of the slag, and the absolute value increment of the zeta potential of the AASC suspension containing the composite retarder is 8.61 mV, compared with 1.99 mV in the system without the composite retarder. Moreover, the AASC pastes activated by WG containing the retarder YP show better rheological properties and lower fluidity loss over time.

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Adsorption of Calcium Lignosulphonate Water Reducer on Alkali-Activated Slag Cement Pastes

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.681.7 ◽

2013 ◽

Vol 681 ◽

pp. 7-10 ◽

Cited By ~ 2

Author(s):

Chang Hui Yang ◽

Qun Pan ◽

Huan Zhou

Keyword(s):

Zeta Potential ◽

Rheological Properties ◽

Slag Cement ◽

Cement Pastes ◽

Alkali Activated Slag ◽

Absolute Value ◽

Adsorption Of Water ◽

Activated Slag ◽

Alkali Activated ◽

Over Time

This paper shows how calcium lignosulphonate（CSL）water reducer affects the adsorption and rheological properties of alkali-activated slag cement (AASC) pastes activated by NaOH. It was concluded that the adsorption of water reducer on AASC pastes depended directly on the dosage of the water reducer and the retarder. Slag particles grounded with the retarder YP-3 adsorbed one and a half times of water reducer CSL as much as pure slag particles at 1% mass of the slag, and the absolute value increment of the zeta potential of the AASC suspension containing the retarder YP-3 is 14.00mV, compared with 9.25mV in the system without YP-3. Besides, the AASC pastes activated by NaOH containing the retarder YP-3 show better rheological properties and lower fluidity loss over time.

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Enhancement of alkali-activated slag cement concretes crack resistance for mitigation of steel reinforcement corrosion

E3S Web of Conferences ◽

10.1051/e3sconf/202016606001 ◽

2020 ◽

Vol 166 ◽

pp. 06001

Author(s):

Pavlo Krivenko ◽

Oleh Petropavlovskyi ◽

Oleksandr Kovalchuk ◽

Igor Rudenko ◽

Oleksandr Konstantynovskyi

Keyword(s):

Crack Resistance ◽

Structure Formation ◽

Water Glass ◽

Sodium Metasilicate ◽

Steel Reinforcement ◽

Reinforcement Corrosion ◽

Slag Cement ◽

Alkali Activated Slag ◽

Activated Slag ◽

Alkali Activated

The paper is devoted to mitigation of steel reinforcement corrosion in alkali-activated slag cement (further, AASC) concretes, based on soluble sodium silicates (further, SSS’s), obtained from high consistensy concrete mixes. Enhancement of AASC fine concretes crack resistance due to modification by complex shrinkage-reducing additives (further, SRA’s) based on surfactants and trisodium phosphate Na3PO .12H2O (further, TSP) was proposed for mitigation of steel reinforcement corrosion. SSS’s were presented by sodium metasilicate (silica modulus 1.0, dry state) and water glass (silica modulus 2.9, density 1400 kg/m3). In case of sodium metasilicate the application of SRA composition “ordinary portland cement clinker – TSP – sodium lignosulphonate – sodium gluconate” provides enhancement of crack resistance starting from early age structure formation with restriction of drying shrinkage from 0,984 to 0,713 mm/m after 80 d. The effect is caused by reduction of water and by higher volume of crystalline hydrates. In turn, SRA presented by compositions “TSP – glycerol” and “TSP – glycerol – polyacrylamide” provide enhancement of AASC fine concretes fracture toughness during late structure formation with increasing ratio of tensile strength in bending to compressive strength up to 37 – 49 % if compare with the reference AASC when water glass is used.

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Factors Influencing the Strength of Alkali-Activated Slag Cement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.368-373.3240 ◽

2011 ◽

Vol 368-373 ◽

pp. 3240-3245

Author(s):

Zhi Jun Zhou ◽

Hui Li ◽

Qiang Song ◽

Bao Jing Shen

Keyword(s):

Compressive Strength ◽

Fly Ash ◽

Silica Fume ◽

Water Glass ◽

Slag Cement ◽

Alkali Activated Slag ◽

Factors Influencing ◽

Activated Slag ◽

Alkali Activated

In this paper, water glass was chosen as activator to prepare Alkali-activated slag(AAS) cement. Effects of modulus and dosage of water glass, and admixture (fly ash, slag and silica fume) on the strength of AAS cement was investigated. It was found that the modulus of water glass had great effect on the strength of AAS cement when the mixing amount of water glass was less than 12%. With the incorporation of fly ash or slag, the strength of AAS cement decreased, however the incorporation of silica fume could promote the flexural and compressive strength of AAS cement slightly.

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The Effect of Surfactant and Alkali on the Surface Tension of Simulated Solutions of Alkali Activated Slag Cement System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.399-401.1246 ◽

2011 ◽

Vol 399-401 ◽

pp. 1246-1250

Author(s):

Xian Feng Liu ◽

Jia Hui Peng ◽

Chang Hui Yang ◽

Yu Yan Shu ◽

Da Chang Wu

Keyword(s):

Surface Tension ◽

Water Glass ◽

High Viscosity ◽

Heat Of Hydration ◽

Slag Cement ◽

Alkali Activated Slag ◽

Cement System ◽

Cement And Concrete ◽

Activated Slag ◽

Alkali Activated

Alkali activated slag cement and concrete are high strength, rapid hardening, low heat of hydration, good durability and so on. Whereas, too high viscosity and bad workability of the fresh mixture is the crux of the matter to embarrass application of alkali-activated slag cement and concrete. Development of special superplasticizer for alkali activated slag cement and concrete is a worth exploring way to solve the problem, and the study on the surface tension of simulated solutions of alkali activated slag cement system is one of the basic researches about the special superplasticizer. In this paper, the surface tension of surfactant-alkali-water was studied by Wilhelmy method. The results showed, first, water-glass had the best efficacity of several alkali activators, when the modulus of water-glass was 1.5 and dosage of water-glass by Na2O was 8%, the surface tension was reduced by 33 mN/m and reduced to 39.9mN/m; second, [CH3(CH2)9]2N(CH3)2Cl had the best efficacity of several surfactants, when the concentration of [CH3(CH2)9]2N(CH3)2Cl was 50g/L, the surface tension was reduced by 35.3 mN/m and reduced to 32.5 mN/m; finally, the effect of surfactant and alkali together on the surface tension of water was complex, surfactants had hardly effective in water glass.

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Effect of Dosage and Modulus of Water Glass on AC Impedance Properties of Alkali-Activated Slag Cement Mortar

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.423-426.1018 ◽

2013 ◽

Vol 423-426 ◽

pp. 1018-1026

Author(s):

Fu Qiang He ◽

Xiao Peng An

Keyword(s):

Compressive Strength ◽

Water Glass ◽

Cement Mortar ◽

Ac Impedance ◽

Slag Cement ◽

Bulk Resistance ◽

Alkali Activated Slag ◽

Activated Slag ◽

Alkali Activated

Compressive strength and AC impedance of mortar made with water-glass-activated slag were investigated as a dependence of modulus (0.5-2.0) and dosage (2-6%) of the water-glass. Results shown that when the dosage of water glass is 2- 4 %, the modulus of the water glass has a little effect on the compressive strength. In the case of the dosage of water glass is beyond 4 %, when modulus of the water glass change from 0.5-1.0, the compressive strength obviously increases with increase of modulus of water glass and when modulus of the water glass change from 1.0-2.0, the modulus of the water glass has a little effect on the compressive strength. The strength increases with increase of the dosage from 2 to 6%. In the case same dosage and modulus, there is a rather good power correlation between the bulk resistance and the activated age. With increase of the dosage, the bulk resistance significantly decreases when the dosage is below 4%. The decreasing degree is small when the dosage is beyond 4%. The decreasing degree derived from the dosage increases with the activated age. The effect of the modulus on the bulk resistance depends on range of the dosage. However, it can be regarded that when the dosage is 4% and 6%, the modulus has small effect on the bulk resistance in the case of all the dosages.

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FT-IR Study on Early-Age Hydration of Alkali-Activated Slag Cement

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.492.429 ◽

2011 ◽

Vol 492 ◽

pp. 429-432 ◽

Cited By ~ 1

Author(s):

Yong Hao Fang ◽

Zheng Long Lu ◽

Zhong Li Wang

Keyword(s):

Water Glass ◽

Glass Network ◽

Early Age ◽

Slag Cement ◽

Alkali Activated Slag ◽

Slag Powder ◽

Ft Ir ◽

Activated Slag ◽

Ir Study ◽

Alkali Activated

The hydration process of alkali-activated slag cement, especially at early-age, was studied by FT-IR, compared with that of Portland cement. The results show that during the hydration of alkali activated slag cement, two processes have taken place, the dissolution of Al3+ from the slag and then the recombination of Al3+ ions with the silicate anions. The former associated with the break of the glass network of slag and the later with the re-polymerization of the silicate and aluminosilicate anions. The rate of break of the glass network increases with the dosage of water glass, which completed in 24 h when the dosage of the water glass solution equivalent to Na2O exceeds 6% of the slag powder. It is confirmed by the IR study that Ca(OH)2 is absent in the hardened alkali activated slag cement paste.

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