Influence of Superplasticizer and Shrinkage-Reducing Admixtures on Early Age Shrinkage of Concrete

Abstract:

The influence of superplasticizer (SP) and shrinkage-reducing admixtures (SRA) on the early age shrinkage of concrete with a controlled slump of 80±10 mm was investigated using a measuring apparatus developed specially. In addition, the influence of early age curing methods on the early age shrinkage of concrete was also studied. The early age shrinkage was increased sharply by the addition of SP when the concrete was exposed to the drying environment after initial setting. While under the same conditions the addition of SRA could reduce the early age shrinkage effectively. However, under sealed curing conditions at the early age, concretes with or without chemical admixtures all exhibited low early age shrinkage, which implies if a good method for curing could available then the addition of SRA will be unnecessary and the adverse effect of SP in enlarging shrinkage could also be eliminated.

• Periodical: Key Engineering Materials (Volumes 405-406)
• Pages: 166-173
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.405-406.166
• Online since: January 2009
• Authors: Xiao Qian Qian, Shu Lin Zhan, Yao Tai Zhu
• Keywords: Early Age Cracking, Sealed Curing, Shrinkage, Superplasticizer

References

[1] G. De Schutter, L. Taerwe, Specific heat and thermal diffusivity of hardening concrete, Magazine of Concrete Research, 47 (1995) 203-208.

DOI: 10.1680/macr.1995.47.172.203

[2] E. Holt, M. Leivo, Cracking risks associated with early age shrinkage, Cement & Concrete Composites 26 (2004) 521-530.

DOI: 10.1016/s0958-9465(03)00068-4

[3] Pietro Lura, Ole Mejlhede Jensen, Autogenous shrinkage in high-performance cement paste: an ev alu ati on o f b as i c m ech ani sms, C em. Co ncr. R es. 3 3 (2 00 3) 22 3-232.

[4] Antonio Princigallo, Pietro Lura, Early development of properties in a cement paste: a numerical and experimental study, Cem. Concr. Res. 33 (2003) 1013-1020.

DOI: 10.1016/s0008-8846(03)00002-4

[5] Ole Mejlhede Jensen, Per Freiesleben Hansen, Autogenous deformation and RH-change in perspective, Cem. Concr. Res. 31 (2001) 1859-1865.

[6] Tazawa, E., Miyazawa, S., Influence of cement and admixture on autogenous shrinkage of cement paste, Cem. Conc. Res. 25(1995)281-287.

DOI: 10.1016/0008-8846(95)00010-0

[7] C. Hua, P. Acker, A. Ehrlacher, Analyses and models of the autogenous shrinkage of hardening cement paste (I. Modelling at macroscopic scale), Cem. Concr. Res. 25 (1995) 1457-1468.

DOI: 10.1016/0008-8846(95)00140-8

[8] Tazawa, E., Miyazawa, S., Experimental study on mechanism of autogenous shrinkage of concrete, Cem. Conc. Res. 25 (1995) 1633-1638.

DOI: 10.1016/0008-8846(95)00159-x

[9] Palacios, F. Puertas, Effect of superplasticizer and shrinkage-reducing amixtures on akali- activated sag pastes and mortars, Cem. Concr. Res. 35 (2005) 1358- 1367.

DOI: 10.1016/j.cemconres.2004.10.014

[10] Tazawa, E., Miyazawa, S., Influence of cement and admixture on autogenous shrinkage of cement paste, Cem. Concr. Res. 25 (1995) 281-287.

DOI: 10.1016/0008-8846(95)00010-0

[11] Qian Xiaoqian, Zhan Shulin, Fang Minghui, et al., Study and application on shrinkage- reducing agent of high performance concrete, New Building Materials, 2003, No. 7, pp.42-45.

[12] Tazawa, E., and Miyazawa, S., Autogenous Shrinkage and its Importance in Concrete, Creep and Shrinkage in Concrete-RILEM 22, ed. Z. P. Bazant and I. Carol, Proceedings from the Fifth International RILEM Symposium, Barcelona, pp.159-168.

DOI: 10.1007/bf02473431

[13] E. Holt, Early age autogenous shrinkage of concrete, PhD thesis, Seattle, University of Washington, (2001).

[14] Zhu Yaotai, Experimental investigation and theoretical modeling on early-age shrinkage cracking in concrete, Academic dissertation for master degree, Hangzhou, Zhejiang University, (2005).