Moisture Diffusion in Shallow Clay Masses
Publication: Journal of Geotechnical and Geoenvironmental Engineering
Volume 133, Issue 10
Abstract
Seasonal cycles of moisture and suction variation in shallow clay masses create repeating episodes of soil shrinkage and swelling that can adversely affect a wide variety of structures including pavements, shallow foundations, piers, and slopes. Design of such structures requires a means of adequately characterizing the depth of this moisture active zone and the magnitude of suction variations within the zone. This paper describes an analytical framework for characterizing suction variations in the moisture active zone and for estimating the soil mass moisture diffusion coefficient, one of the critical parameters governing the rate of moisture penetration in the soil. The paper presents extensions to an existing analysis for sinusoidal variations in surface suction to general nonsinusoidal conditions. It also presents a review of moisture diffusion coefficient data obtained from field measurements and shows that these data exceed laboratory measurements on intact soil specimens by up to two orders of magnitude. A conceptual model of moisture diffusion in a fractured soil mass provides an explanation of the differences between the field and laboratory values of the moisture diffusion coefficient.
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Acknowledgments
This project was conducted in cooperation with TxDOT and FHwA. The writers would like to express their appreciation to Program Coordinator Elias Rmeili, and Project Director Richard Williamee, from the Texas Department of Transportation, for their support and assistance throughout this project. The writers thank the members of the Project Monitoring Committee: Mark McDaniel, Darlene Goehl, Jamshid Shirali, David Fowler, and Gary Williams. The writers would also like to acknowledge the contributions of Texas A&M University graduate research assistants Gyeong Taek Hong, Eeshani Sood, and Anshuman Thakur. Finally, the writers would like to express their appreciation to Benson Chair Professor Robert Lytton for his guidance and support throughout this project.
References
Aubeny, C. P., and Lytton, R. L. (2004). “Shallow slides in compacted high plasticity clay slopes.” J. Geotech. Geoenviron. Eng., 130(7), 717–727.
Biddle, P. G. (1998) Tree root damage to buildings, Vol. 1, Willowmead, Wantage, U.K.
Cameron, D. A. (2001). “The extent of desiccation near trees in a semiarid environment.” Geotechnical and geological engineering, Vol. 19, Kluwer Academic, Dordrecht, The Netherlands, 357–370.
Desai, C., and Christian, J. (1977). Numerical methods in geotechnical engineering, McGraw-Hill, New York.
Ferregut, C., and Picornell, M. (1991). “Reliability analysis of drilled piers in expansive soils.” Can. Geotech. J. 28(6), 834–842.
Hibbitt, Karlsson, & Sorensen, Inc. (HKS). (2003) ABAQUS version 6.4 user’s manuals, HKS, Providence, R.I.
Hildebrand, F. B. (1976). Advanced calculus for applications, Prentice-Hill, Englewood Cliffs, N.J.
Jayatilaka, R., Gay, D. A., Lytton, R. L., and Wray, W. K. (1993). “Effectiveness of controlling pavement roughness with vertical moisture barriers.” Research Rep. No. FHWA/TX-92/1165-2F, Texas Transportation Institute, Texas A&M Univ., College Station, Tex.
Jayatilaka, R., and Lytton, R. L. (1999). “Prediction of expansive clay roughness in pavements with vertical moisture barriers.” Research Rep. No. FHWA/TX-98/197-28F, Texas Transportation Institute, Texas A&M Univ., College Station, Tex.
Knight, M. J. (1971). “Structural analysis of selected duplex soil.” Doctoral dissertation, Univ. of Melbourne, Melbourne, Australia.
Lytton, R. (1997). “Engineering structures in expansive soils.” Proc., 3rd Int. Symp. on Unsaturated Soils, Keynote address, Rio de Janeiro, Brazil.
Lytton, R. L., Aubeny, C. P., and Bulut, R. (2000). “Design procedures for pavements on expansive soils.” Research Rep. No. FHWA/TX-05/0-4518-1, Texas Transportation Institute, Texas A&M Univ., College Station, Tex.
McKeen, R. G. (1981). “Design of airport pavements on expansive soils.” DOT/FAA/RD-81/25, Systems-Research and Development Service, Federal Aviation Administration, Washington, D.C.
McKeen, R. G., and Johnson, L. D. (1990). “Climate-controlled soil design parameters for mat foundations.” J. Geotech. Engrg., 116(7), 1073–1094.
Mitchell, P. W. (1979). “The structural analysis of footings on expansive soils.” Research Rep. No. 1, K. W. G. Smith and Associates Pty. Ltd., Newton, South Australia.
Russam, K., and Coleman, J. D. (1961). “The effect of climatic factors on subgrade moisture conditions.” Geotechnique, 11(1), 22–28.
Sherard, J. L. (1973). “Embankment dam cracking.” Embankment dam engineering, Wiley, New York, 271–353.
Snethen, D. R., Johnson, L. D., and Patrick, D. M. (1977). “An investigation of the natural microscale mechanisms that cause volume change in expansive clays.” Rep. No. FHWA-RD-77-75, U.S. Army Engineer Waterways Experiment Station, Federal Highway Administration, Washington, D.C.
Thornthwaite, C. W. (1948). “An approach toward a rational classification of climate,” Geogr. Rev., 38(10), 54–94.
Wray, W. K. (1989). “Mitigation of damage to structures supported on expansive soils.” Final Rep., National Science Foundation Grant No. EKE-8320493, Texas Tech. Univ., Lubbock, Tex.
Information & Authors
Information
Published In
Journal of Geotechnical and Geoenvironmental Engineering
Volume 133 • Issue 10 • October 2007
Pages: 1241 - 1248
Copyright
© 2007 ASCE.
History
Received: Apr 10, 2006
Accepted: Apr 3, 2007
Published online: Oct 1, 2007
Published in print: Oct 2007
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