Experimental Study on Compatibility between Alkali-Free Liquid Concrete Accelerators and Cement

Abstract:

This paper selected two kinds of alkali-free liquid concrete accelerators and tested their compatibility with ordinary Portland cement, Portland cement and moderate heat Portland cement by measuring the setting times, compressive strength and compressive strength ratio of samples. The results showed that the compatibility is good between alkali-free accelerators and two types of cement: ordinary Portland cement and moderate heat Portland cement. However, the compatibility of two accelerators and Portland cement are quite different, the compatibility of AFA-2 accelerator is excellent, but AFA-1 accelerator is very poor. The setting times of alkali-free accelerators is mainly influenced by the mixing materials content, gypsum content, C₃A and C₃S content. In order to ensure the mechanical properties and durability of concrete, the setting times of new concrete accelerator is not the shorter the better, the appropriate initial and final setting times are 1min30s~5min and 4min~ 12min respectively.

• Periodical: Applied Mechanics and Materials (Volumes 438-439)
• Pages: 102-107
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.438-439.102
• Online since: October 2013
• Authors: Wen Kang Guo, Li Wang, Shu Yin Wang, Dao Yin Lan, Sheng Ping Li
• Keywords: Accelerator, Alkali-Free, Cement, Compatibility, Compressive Strength, Compressive Strength Ratio, Setting Times

References

[1] Luiz Roberto Prudhcio Jr, Accelerating admixtures for shotcrete, Cement and Concrete Composites, 20 (1998) 213-219.

DOI: 10.1016/s0958-9465(98)80007-3

[2] C. Maltese, C. Pistolesi, A. Bravo, et al, A case history: Effect of moisture on the setting behaviour of a Portland cement reacting with an alkali-free accelerator, Cement and Concrete Research, 37 (2007) 856-865.

DOI: 10.1016/j.cemconres.2007.02.020

[3] Z. Pan, W. Lv, J. Chen, Performance and action mechanism of alkali-free liquid accelerating agent, Mine Construction Technology, 5 (2006) 25-29.

[4] W. Lv, F. Li, Z. Pan, Improvement of alkali-free cement setting accelerator and its acceleration mechanism, Journal of Nanjing University of Technology, 2 (2007) 34-39.

[5] Nick Varley, Research and development experiences with the use of alkali free accelerators in Asia, Tunneling and Underground Space Technology, 21 (2006) 409-456.

DOI: 10.1016/j.tust.2005.12.056

[6] L. R. Prudêncio, H. S. Armelin, P. Helene, Interaction between accelerating admixtures and Portland cement for shotcrete: the influence of the admixture's chemical base and the correlation between paste tests and shotcrete performance, ACI Materials Journal, 6 (1996).

DOI: 10.14359/9869

[7] N. De Beliea, C. U. Grosseb, J. Kurzb, H. W. Reinhardtb, Ultrasound monitoring of the influence of different accelerating admixtures and cement types for shotcrete on setting and hardening behavior, Cement and Concrete Research, 6 (2005).

DOI: 10.1016/j.cemconres.2005.03.011

[8] J. Zhang, Study on compatibility between cement and liquid accelerator in shotcrete, Tunnel Construction, 1 (2010) 6-8.