Influence of Polymer Additives on Mechanical Fracture Properties and on Shrinkage of Alkali Activated Slag Mortars

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Alkali-activated slags represent an alternative to ordinary Portland cement due to reducing the environmental impact of the building industry. In spite of the numerous advantages of alkali activated slag mortars, alkali-activated aluminosilicates have big disadvantage – high value of shrinkage followed by formation of microcracks. This effect is caused by both autogenous and drying shrinkage and it finally results in volume contraction, microcracking and deterioration of the mechanical fracture properties. Therefore, using various types of polymer admixtures can overcome these problems. The aim of this paper is to present the effect of shrinkage-reducing admixture Peramin® SRA 40, polymer polyethylene glycol 1000 and polypropylene glycol on shrinkage and mechanical fracture characteristics of alkali-activated slag mortars. These admixtures were used in amount 0–2.0% weight of slag. The results showed that with increasing content of admixtures compressive and flexural strength decreased. Fracture tests with acoustic emission activity during this testing were carried out. Addition of 2% Peramin® SRA decreased shrinkage by 55%, but with 1% of Peramin® SRA the shrinkage was reduced only by 10%. Specimen with 1% of Peramin® is the most durable material, but more brittle compared to specimens with 1 and 2% of polypropylene glycol.

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Edited by:

Šárka Nenadálová, Vlastimil Bílek, Zbyněk Keršner, Stanislav Seitl and Dr. Hana Šimonová

Pages:

39-44

Citation:

O. Mikhailova et al., "Influence of Polymer Additives on Mechanical Fracture Properties and on Shrinkage of Alkali Activated Slag Mortars", Key Engineering Materials, Vol. 761, pp. 39-44, 2018

Online since:

January 2018

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$38.00

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[1] Mao-chieh Chi, Jiang-jhy Chang, Ran Huang, Strength and Drying Shrinkage of Alkali-Activated Slag Paste and Mortar, Advances in Civil Engineering. 2012 (2012) 1 – 7.

DOI: https://doi.org/10.1155/2012/579732

[2] Hailong Ye, C. Cartwright, F. Rajabipour, A. Radlińska, Effect of drying rate on shrinkage of alkali-activated slag cements, Proc. Of the 4th International Conference on the Durability of Concrete Structures, West Lafayette, IN, USA, July (2014).

DOI: https://doi.org/10.5703/1288284315409

[3] M. A. Cincotto, A. A. Melo, W. L. Repette, Effect of different activators type and dosages and relation with autogenous shrinkage of activated blast furnace slag cement, Proc. of the 11th International Congress on the Chemistry of Cement, Durban, South Africa (2003).

DOI: https://doi.org/10.1016/j.cemconres.2007.11.002

[4] M. Palacios, F. Puertas, Effect of shrinkage-reducing admixtures on the properties of alkali-activated slag mortars and pastes, Cement and Concrete Research. 37 (2007) 691–702.

DOI: https://doi.org/10.1016/j.cemconres.2006.11.021

[5] M. Palacios, F. Puertas, Effect of superplasticizer and shrinkage-reducing admixtures on alkali-activated slag pastes and mortar, Cement and Concrete Research. 35 (2005) 1358 – 1367.

DOI: https://doi.org/10.1016/j.cemconres.2004.10.014

[6] Cahit Bilim, Okan Karahan, Cengiz Duran Atiş, Serhan İlkentapar, Effects of Chemical Admixtures and Curing Conditions on some Properties of Alkali-Activated Cementless Slag Mixtures. KSCE Journal of Civil Engineering. 19 (3) (2015) 733-741.

DOI: https://doi.org/10.1007/s12205-015-0629-0

[7] T. Bakharev, J.G. Sanjayan, Y. -B. Cheng, Effect of admixtures on properties of alkali-activated slag concrete, Cement and Concrete Research. 30 (2000), 1367–1374.

DOI: https://doi.org/10.1016/s0008-8846(00)00349-5

[8] F. Collins, J.G. Sanjayan, Cracking tendency of alkali-activated slag concrete subjected to restrained shrinkage, Cement and Concrete Research. 30 (2000) 791–798.

DOI: https://doi.org/10.1016/s0008-8846(00)00243-x

[9] Collins F, Sanjayan J.G. Microcracking and strength development of alkali-activated slag concrete, Cem Concr Compos. 23 (2001) 345–352.

DOI: https://doi.org/10.1016/s0958-9465(01)00003-8

[10] B.L. Karihaloo, Fracture Mechanics and Structural Concrete. Longman Scientific & Technical, Harlow, UK, 1995, 346.

[11] A. Dakhane, S. Das, S. Kailas, N. Neithalath, Elucidating the Crack Resistance of Alkali-Activated Slag Mortars Using Coupled Fracture Tests and Image Correlation, J. Am. Ceram. Soc. 99 (1) (2016) 273–280.

DOI: https://doi.org/10.1111/jace.13960

[12] Qixuan Li, Liangcai Cai, Yawei Fu, Haifu Wang, Yong Zou, Fracture properties and response surface methodology model of alkali-slag concrete under freeze–thaw cycles, Construction and Building Materials. 93 (2015) 620–626.

DOI: https://doi.org/10.1016/j.conbuildmat.2015.06.037

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