Hydrates and Paste Structure of Slag-Fly Ash Based Cementitious Materials

Abstract:

Cascade grinding mode is often applied to prepare Slag-Fly Ash Based cementitious materials with high volume of fly ash and slag and less cement clinker. This process has low water requirement and well fluidity, which is suitable to prepare HPC．When the W/C is 0.36, the 28d compressive strength is 58.93 Mpa, 28d flexural strength is 14.26 Mpa. By X-Ray diffraction analysis (XRD) and Scanning Electron Microscope (SEM) analysis the results show that main materials in grinded sample are well activated by mechanical force and chemical action; more Aft are produced and observed in 3 days hydration products and the great amount of C-S-H gel has continuously generated with the growth of hydration time. By Infrared(IR) analysis, the results show that in the hydration products, the network of Silicon Oxygen Tetrahedron and Aluminum Oxygen Tetrahedra have depolymerized significantly; in the hydration process and various raw materials mutually promoted each other to accelerate the hydration reaction. The hydrates and paste structure of slag-fly ash based cementitious materials were explained．

• Periodical: Advanced Materials Research (Volumes 450-451)
• Pages: 557-562
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.450-451.557
• Online since: January 2012
• Authors: Cheng Hong Fu, Wen Ni, Hui Wu, De Zhong Li
• Keywords: Cementitious Material, Fly Ash (FA), Hydrates, IR, Paste Structure, SEM, Slag, X-Ray Diffraction (XRD)

References

[1] M.L. Berndt. Properties of sustainable concrete containing fly ash, slag and recycled concrete aggregate. Construre Building Materials, Vol.23(2009) ,p.2606–2613

DOI: 10.1016/j.conbuildmat.2009.02.011

[2] D. A. Michael, P.B. Bamforth. Modelling chloride diffusion in concrete: Effect of fly ash and slag. Cement and Concrete Research, Vol.29(1999) ,p.487–495

DOI: 10.1016/s0008-8846(98)00192-6

[3] P. K. Mehta. Reducing the environmental impact of concrete. Concrete International, Vol.23(2001) ,pp.61-63

[4] X. F. Zhang, W Ni, W Wang．Preparation of Cementitious Material with Slag and Fly-ash．Materials Review, Vol.23(2009) ,pp.93-95

[5] F Puertas, R. S.Martinez, S. A. Alonso, et al．Alkali Activated Fly Ash/Slag Cement Strength behavior and hydration products. Cement and Concrete Research,Vol.12(2000) ,pp.1625-1632．

DOI: 10.1016/s0008-8846(00)00298-2

[6] M Yang, X. W. Sun, W. X. Li．Experimental Study of the Alkali Activated Slag Cementing Materials．Research and Application of Building Materials, Vol. 3(2010) ,pp.1-3

[7] E Wang, W Ni, H Sun.The Principle and Development of the Technique for Preparing Industrial Slags-Based Geopolymer．Multipurpose Utilization of Mineral Resources, Vol.2 (2005) ,pp.30-34

[8] P. S. Singh, M Trigg, I K Burgar, et al. Geopolymer formation processes at room temperature studied by 29Si and 27Al MAS-NMR. Materials Science and Engineering A, Vol.,1-2(2005) ,pp.392-402

DOI: 10.1016/j.msea.2005.02.002

[9] Y. Yao, L. Wang, P. Tian. High Performance Concrete. Chemical Industry Press, (BJ)2006 ,pp.24-45

[10] D. K. Zhang, L. Wang. Research development and discussion of High performance coment.Cement, Vol. 12 (2006) ,pp.7-12

[11] F. Puertas, S. M. Ramírez, S．Alonso, etal．Alkali-activated fly ash/slag cements: Strength behaviour and hydration products．Cement and Concrete Research, Vol. 30(2000),pp.1625-1632.

DOI: 10.1016/s0008-8846(00)00298-2

[12] P. J．Schilling, Leslie G．Butler, Amitava Roy, etal．29Si and 27Al MAS-NMR of NaOH-Activated Blast-Furnace Slag．Journal of the American Ceramic Society, Vol. 77 77(2006),pp.2363-2368

DOI: 10.1111/j.1151-2916.1994.tb04606.x

[13] P. N. Zhu, Preliminary study on the relationship between structure and activity of blast furnace slag. Chinese ceramic society, Vol. 11 (1983),pp.290-296