Rehydration Performance of Binary Binders Made with Dehydrated Cement Paste and Phosphogypsum

Abstract:

This paper presents the rehydration performance of binary binders made with dehydrated cement paste (DCP) and phosphogypsum (GP). DCP was obtained by thermal treatment of hardened cement pastes in which the initial water to cement ratio was 0.5. DCP we mixed with phosphogypsum (PG) to prepare the binary binders . The effect of PG on the physical and mechanical properties of the binary binders was investigated. Scanning electron microscope (SEM) was used to indentify the structural characteristics of the rehydration products. The results showed that the setting time was prolonged and the compressive strength increased slightly by mixing DCP with PG. Microstructural observations indicated that an remarkable amount of ettringite intergrows with the hydrated calcium silicate to form a network structure. Thus, the addition of phosphogypsum can not only utilize the industrial by-product, but enhances the hydraulic properties of the DCP.

• Periodical: Key Engineering Materials (Volumes 474-476)
• Pages: 1238-1242
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.474-476.1238
• Online since: April 2011
• Authors: Tao Sun, Zhong He Shui, Tao Huo
• Keywords: Binary Binder, Dehydrated Cement Paste, Ettringite, Microstructural Characteristic, Phosphogypsum (PG)

References

[1] Olorunsogo, F. T., N. Padayachee: Cement and Concrete Research Vol. 32 No. 2 (2002), pp.179-185.

[2] LU L.N., He Y.J., Hu S.G. et al.: Journal of The Chinese Ceramic Society Vol. 36 No. 10 (2008), pp.1343-1347.

[3] GUERRERO A., GONŇI S., MACĬAS A., et al.: Cement and Concrete Research Vol. 30 No. 4 (2000), pp.553-559.

[4] He Y.J. Research on recycling utilization of cement-based solid waste (in Chinese, dissertation), Wuhan University of Technology, (2006).

[5] Hu S.G., He Y. J: Journal Of The Chinese Ceramic Society Vol. 35 No. 5 (2007), pp.593-599.

[6] Shui Z.H., Xuan D.X., Wan H.W. et al.: Construction and Building Materials Vol. 22 No. 8 (2008), pp.1723-1729.

[7] Kuryatnyk T., C. A. da Luz, et al.: Journal of Hazardous Materials Vol. 160 No. 2 (2008), pp.681-687.

[8] Yang J.K. Jiakuan Yang. et al.: Construction and Building Materials Vol. 23 No. 2 (2009), pp.687-693.

[9] Smadi M.M., Haddad R.H., Akour A. M: Cement and Concrete Research Vol. 29 No. 9 (1999), pp.1419-1425.

DOI: 10.1016/s0008-8846(99)00107-6

[10] Singh M. (2002), Cement and Concrete Research, 32(7), 1033–1038. Vol. 32 No. 7 (1999), pp.1033-1038.

DOI: 10.1016/s0008-8846(02)00723-8

[11] Altun I.A., Sert Y: Cement and Concrete Research Vol. 34 No. 4 (2004), pp.677-680.

[12] Singh M., Garg M: Construction and Building Materials Vol. 19 No. 1 (2005), pp.25-29.

[13] Degirmenci N: Construction and Building Materials Vol. 22 No. 8 (2008), pp.1857-1862. Figure 4. The SEM micrographs of binders: (a) DG0, 28d; (b) DG8 3d; (c) DG8, 28d.