Interior Humidity of Concrete under Dry-Wet Cycles
Publication: Journal of Materials in Civil Engineering
Volume 24, Issue 3
Abstract
The dry-wet cycle is one of the aggressive environmental conditions suffered by concrete. This paper focuses on the experimental study and theoretical simulation of water distribution in normal- and high-strength concrete through dry-wet cycles. The experimental results show that under dry-wet cycles, the variation in the interior humidity of concrete occurs mainly within a certain depth from the drying/wetting face. This depth is called the influencing depth under dry-wet cycles. The interior relative humidity of concrete within the influencing region periodically changes under dry-wet cycles. As concrete undergoes wetting, a fast rise in interior humidity occurs in a short time, and finally the relative humidity reaches approximately 100%. By contrast, as concrete undergoes drying, the interior relative humidity does not drop immediately, but in a more gradual manner. In the modeling, a model taking both cement hydration and moisture diffusion into account synchronously is used to simulate the moisture distribution in concrete under dry-wet cycles. A comparison between model and experimental results concludes that the model can predict the moisture distribution in concrete, as well as its variations, through dry-wet cycles.
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Acknowledgments
This work has been supported by a grant from the National Science Foundation of China (No. NSFC50978143) and a grant from National Basic Research Program of China (No. UNSPECIFIED2009CB623200) to Tsinghua University.
References
Akita, H., Fujiwara, T., and Ozaka, Y. (1997). “A practical procedure for the analysis of moisture transfer within concrete due to drying.” Mag. Concr. Res., 49(179), 129–137.
Andrade, C., Sarria, J., and Alonso, C. (1999). “Relative humidity in the interior of concrete exposed to natural and artificial weathering.” Cem. Concr. Res., 29(8), 1249–1259.
Ayano, T., and Wittmann, F. H. (2002). “Drying, moisture distribution, and shrinkage of cement-based materials.” Mater. Struct., 35(247), 134–140.
Baroghel-Bouny, V., Mainguy, M., Lassabatere, T., and Coussy, O. (1999). “Characterization and identification of equilibrium and transfer moisture properties for ordinary and high-performance cementitious materials.” Cem. Concr. Res., 29(8), 1225–1238.
Bazant, Z. P., and Najjar, L. J. (1972). “Nonlinear water diffusion in nonsaturated concrete.” Mater. Struct., 5(1), 3–20.
Bissonnette, B., Pierre, P., and Pigeon, M. (1999). “Influence of key parameters on drying shrinkage of cementitious materials.” Cem. Concr. Res., 29(10), 1655–1662.
Chanvillard, G., and Daloia, L. (1997). “Concrete strength estimation at early age: Modification of the method of equivalent age.” ACI Mater. J., 94(6), 220–227.
Hansen, F. P., and Pederson, E. J. (1985). “Curing of concrete structures.” Draft DEB-Guide to durable concrete structures, Switzerland.
Hobbs, D. W., Matthews, J. D., and Marsh, B. K. (1998). Minimum requirements of durable concrete: carbonation- and chloride-induced corrosion, freeze-thaw attack and chemical attack, British Cement Association, Crowthorne, UK.
Kellsen, K., and Detwiler, R. J. (1993). “Later-age strength prediction by a modified maturity model.” ACI Mater. J., 90(3), 220–227.
Kim, J. K. (2001). “Estimation of compressive strength by a new apparent activation energy function.” Cem. Concr. Res., 31(2), 217–225.
Leech, C., Lockington, D., and Dux, P. (2003). “Unsaturated diffusivity functions for concrete derived from NMR images.” Mater. Struct., 36(6), 413–418.
Li, C. (2009). “Study on water and ionic transport processes in cover concrete under drying-wetting cycles.” Doctoral thesis, Beijing: Tsinghua Univ., In Chinese.
Lockington, D., Parlange, J-Y., and Dux, P. (1999). “Sorptivity and the estimation of water penetration into unsaturated concrete.” Mater. Struct., 32(5), 342–347.
Nilsson, L. O. (2002). “Long-term moisture transport in high performance concrete.” Mater. Struct., 35(10), 641–649.
Oh, B. H., and Cha, S. W. (2003). “Nonlinear analysis of temperature and moisture distribution in early-age concrete structures based on degree of hydration.” ACI Mater. J., 100(5), 361–370.
Pane, I., and Hansen, W. (2002). “Concrete hydration and mechanical properties under nonisothermal conditions.” ACI Mater. J., 99(6), 534–542.
Parrott, L. J. (1995). “Influence of cement type and curing on the drying and air permeability of cover concrete.” Mag. Concr. Res., 47(171), 103–111.
Powers, T. C., and Brownyard, T. L. (1946-1947 ). “Studies of physical properties of hardened Portland cement past.” American Concrete Institute Journal, 43 (Oct. 1946-April 1947), Bulletin 22, Research Laboratories of the Portland Cement Association, Chicago.
Rastrup, E. (1954). “Heat of hydration.” Mag. Concr. Res., 6(17), 127–140.
Schindler, A. K., and Folliard, K. J. (2005). “Heat of hydration models for cementitious materials.” ACI Mater. J., 102(1), 24–33.
Zhang, J., Hou, D., and Chen, H. (2011a). “Experimental and theoretical studies on shrinkage of concrete at early-ages.” J. Mater. Civ. Eng., 23(3), 330–334.
Zhang, J., Hou, D., Gao, Y., and Sun, W. (2011b). “Determination of moisture diffusion coefficient of early-age concrete from interior humidity measurements.” Drying Technol., 29(6), 689–696.
Zhang, J., Hou, D., and Sun, W. (2010). “Experimental study on the relationship between shrinkage and interior humidity of concrete at early age.” Mag. Concr. Res., 62(3), 191–199.
Zhang, J., Qi, K., and Huang, Y. (2009). “Calculation of moisture distribution in early-age concrete.” J. Eng. Mech., 135(8), 871–880.
Zhang, Z. B., and Zhang, J. (2006). “Experimental study on the relationship between shrinkage strain and environmental humidity of concrete.” J. Build. Mater., 6(6), 720–723 (in Chinese).
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© 2012 American Society of Civil Engineers.
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Received: Jan 7, 2011
Accepted: Aug 24, 2011
Published online: Aug 26, 2011
Published in print: Mar 1, 2012
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