Unsaturated water transport of cement-based materials

Abstract

The slice-weighing method was used to investigate the unsaturated water transport of different cement pastes. The experimental results show that a sharp wetting front existed during water transport, the transport can be described by a non-linear diffusion equation, and transport coefficient of different materials exhibit various rules with water content of materials. The addition of fly-ash decreases transport coefficient of cement pastes in all the various water contents, even changes the transport mechanism.

Keywords

water transport / unsaturated flow / slice-weighing method / transport coefficient

References

[1] Wu Z.W., Lian H.Z. High Performance Concrete[M], 1999. Beijing: Chinese Railroad Press.

[2] Qin W. Holistic View of Durability of Concrete Structures[J]. Architecture Technology, 2000, 34(1): 19-22.

[3] Schupack M. How to Make Today’s Concrete durable for Tomorrow[M], 1985. London: The Institute of Civil Engineering.

[4] Zhao T. Concrete Permeability[M], 2006. Beijing: Science Press.

[5] Dunagan W. H. Methods for Measuring the Passage of Water through Concrete[C]. Proceedings of the American society for Testing Materials, 1939, 39: 866-880.

[6] J A Da. Cunha Neto Bellini. Moisture Transport at Present of a Temperature Gradient: Experimental Characterization of Cement Concrete[D]. University of Joseph Fourier-GrenobleI, 1992: 69

[7] Pel L. Moisture Transport in Porous Building Materials[D], 1995. Netherlands: Eindhoven University of Technology. 127