Determination the Constant Parameters of Van Genuchten-Mualem and Gardner’s Equations Using a Statistical Model to Estimate the Permeability in Unsaturated Soil

Document Type : Research Paper

Authors

1 Graduate Student, University College of Agriculture and Natural Resources, University of Tehran

2 Associate Professor, University College of Agriculture and Natural Resources, University of Tehran

3 Assistant Professor, University College of Agriculture and Natural Resources, University of Tehran

Abstract

Availability of accurate information regarding permeability of soil is needed in planning for the development projects, especially hydraulic structures. Laboratory determination of unsaturated permeability of soil involves high costs and is very time taking. Therefore, it is preferred to determine it using such indirect methods as making use of soil-water characteristic curve. These indirect methods are of constant parameters the determination of which needs such special information of soil water characteristic curve as residual and saturated water contents. Through initially examining a statistical model ( not a function of residual and saturated water contents) the  permeability coefficients of unsaturated soil that were in acceptable correlation with famous models were determined. The constant parameters of some of the equations for estimation of the permeability of unsaturated soil were then estimated. The results finally show a high accuracy of the proposed model for a determination of the constant parameters.

Keywords

References

Brooks, R. H. and Corey, A. T. (1964). Hydraulic properties of porous media, Colorado State University Hydrology Paper, No. 3. Fort Collins, CO.
Burdine, N. T. (1953). Relative permeability calculations from pore size distribution data, Transactions of the Metallurgical Society of AIME, Vol. 198, 71–78.
Childs, E. C. and Collis-George, N. (1950). The permeability of porous materials, Proceedings of the Royal Society, London, Series A, Vol. 201A, 392–405.
Darcy, H. (1856). Histoire des Foundataines Publique de Dijon, Dalmont, Paris, 590–594.
Fredlund, D. G., Rahardjo, H., and Fredlund, M. D. (2012). Unsaturated Soil Mechanics in Engineering Practice, Wiley, New York.
Fredlund, D. G. and Xing, A. (1994). Equations for the soil-water characteristic curve, Canadian Geotechnical Journal, Vol. 31, No. 3, 521–532.
Fredlund, D. G., Xing, A., and Huang, S. Y. (1994b). Predicting the permeability function for unsaturated soils using the soil water characteristic curve, Canadian Geotechnical Journal, Vol. 31, No. 4, 533–546.
Gardner, W. R. and Widtsoe, J. A. (1921). The movement of soil moisture, Soil Science Journal, Vol. 11, pp. 215–232.
Gardner, W. R. (1958a). Mathematics of isothermal water conduction in unsaturated soils, Highway Research Board Special Report 40, presented at the International Symposium on Physico-Chemical Phenomenon in Soils, Washington, DC, 78–87.
Green, R. E. and Corey, J. C. (1971a). Calculation of hydraulic conductivity: A further evaluation of some predictive methods, Soil Science Society of America Proceedings, Vol. 35, 3–8.
Kholoosi, M. M., Estabragh, A. R., and Pashankpoor, S. (2014a). Estimation of Unsaturated Permeability Using Statistical Methods, 1st National Conference on Soil Mechanics and foundation Engineering, 3-4 Dec., Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran, 376.(In Farsi)
Kholoosi, M. M., Estabragh, A. R., Pashankpoor, S., and Arabzadeh, A. (2014b). Calculation of Soil Water Characteristic curve Parameter Using Genetic Algorithm by R, 1st National Conference on Soil Mechanics and foundation Engineering, 3-4 Dec., Faculty of Civil Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran, 377. (In Farsi)
Kunze, R. J., Uehara, G., and Graham, K. (1968). Factors important in the calculation of hydraulic conductivity, Soil Science Society of America Proceedings, Vol. 32, 760–765.
Leong, E. C. and Rahardjo, H. (1997a). Permeability functions for unsaturated soils, Journal of Geotechnical and Geoenvironmental Engineering, ASCE, Vol. 123, No. 12, 1118–1126.
Likos, W. J. and Lu, N. (2004). Unsaturated Soil, Wiley, New York.
Marshall, T. J. (1958). A relation between permeability and size distribution of pores, Soil Science Journal, Vol. 9, 1–8.
Mualem, Y. (1976a). A new model for predicting hydraulic conductivity of unsaturated porous media, Water Resources Research, Vol. 12, 513–522.
Mualem, Y. (1978). Hydraulic conductivity of unsaturated porous media: Generalized macroscopic approach, Water Resources Research, 14(2), 325–334.
Rahimi, A., Rahardjo, H., and Leong, E. C. (2014). Effect of range of soil–water characteristic curve measurements on estimation of permeability function, Engineering Geology Journal, Elsevier, Vol. 185, 96–104.
Rajkai, K., Kabos, S., and Van Genuchten, M.Th. (2004). Estimation of water retention characteristics from soil properties: comparison of linear, nonlinear and concomitant variable methods. Soil & Tillage Research, ELSEVIER. 79, 145–152.
Van Genuchten, M. T. (1980). Closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J. 44, 892–898.
Iranian Journal of Soil and Water Research
Volume 46, Issue 3 - Serial Number 3
October 2015
Pages 519-528

Files

Share

How to cite

Statistics