Effects of alkali dosage and silicate modulus on autogenous shrinkage of alkali-activated slag cement paste

Nowadays, alkali-activated cements (AACs) are the most promising alternatives to ordinary portland cement (OPC). Such cements characterized by better strength and corrosion resistance that determine improved durability of materials based on them. However, the shrinkage of AAC systems is noticeably higher compared with OPC. The purpose of this work was to study the shrinkage behavior of alkali-activated slag cement (AASC) pastes. To improve early age performance of AASCs – OPC and Ca(OH)2, as mineral additives, were added to the designed cement mixtures. The properties, like, flexural and compressive strength of cement mortars, chemical shrinkage, autogenous shrinkage and drying shrinkage of cement pastes were studied. The results showed that the chemical shrinkage, autogenous shrinkage and drying shrinkage at 28 days were between 0.064 – 0.074 ml/g, 4.5 – 7.9 mm/m and 3.3 – 4.9 mm/m, respectively. The relationship between the nature of alkaline components, the type of mineral additives and the shrinkage behavior of cements were discussed.

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Automated identification of the aggregate–paste interfacial transition zone in mortars of silica sand with Portland or alkali-activated slag cement paste

Cement and Concrete Research ◽

10.1016/s0008-8846(00)00254-4 ◽

2000 ◽

Vol 30 (6) ◽

pp. 849-854 ◽

Cited By ~ 41

Author(s):

A.R Brough ◽

A Atkinson

Keyword(s):

Transition Zone ◽

Cement Paste ◽

Interfacial Transition Zone ◽

Silica Sand ◽

Automated Identification ◽

Slag Cement ◽

Alkali Activated Slag ◽

Activated Slag ◽

Alkali Activated

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Effect of Quartz Powder on the Strength and Shrinkage of Alkali-Activated Slag Cement

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.602-604.972 ◽

2012 ◽

Vol 602-604 ◽

pp. 972-975

Author(s):

Xue Lian Yuan ◽

Yong Hao Fang ◽

Ya Min Gu

Keyword(s):

Cement Paste ◽

Hardened Cement ◽

Quartz Powder ◽

Slag Cement ◽

Hardened Cement Paste ◽

Alkali Activated Slag ◽

Slag Powder ◽

Dry Shrinkage ◽

Activated Slag ◽

Alkali Activated

Quartz powder with different fineness were added into alkali activated slag cement to reduce the drying shringkage of the hardened cement paste. Experimental results showed that partially replacing the slag powder with quartz powder will reduce the water requirement of normal consistency, dry shrinkage and early age compressive and flexural strength of alkali-activated slag cement (AASC), however, the flexural/compressive strength ratio and the fracture toughness will be increased and so does the later strength. The fracture section of specimen of quartz powder modified alkali-activates slag cement paste has a rougher texture than that of pure alkali-activates slag cement paste.

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