Rapidly Determining the Unsaturated Permeability by Transient Two-Steps Outflow Experiment

  • Tiande Wen
  • Longtan ShaoEmail author
  • Xiaoxia Guo
Conference paper


Numerous methods have been developed to measure the unsaturated permeability in multi-step outflow experiments. Silicon micro-powder (SMP) and Guangxi Guiping clay (GGC) have been conducted by transient outflow methods in this paper. The water release upon two-steps increase in matric suction. For each step of the experiment, the water outflow from the soil specimen is weighed in real time in order to determine the change of the water content in the specimen. As a gas pressure is exerted, the difference of the matric potential between the transient water content curve (TWCC) and the soil water retention curve (SWRC) at the same water content is calculated. This difference is considered to have the potential to drive the flow of pore water. Then, the unsaturated permeability can be calculated by using Darcy’s law. This two-steps measurement method agrees with the Gardner outflow analysis method (1956), which have the same ranges of variation for unsaturated permeability. Additionally, the test time is greatly reduced, and generally takes 10 days.


Unsaturated soil Two-steps outflow experiment Unsaturated permeability 



This research was funded by the National Natural Science Foundation of China (No. 51479023).


  1. ASTM D7664: Standard Test Methods for Measurement of Hydraulic Conductivity of Unsaturated Soils. Annual Book of ASTM Standards, vol. 4.09. ASTM International, West Conshohocken (2010)Google Scholar
  2. Abuhejleh, A.N., Znidarčić, D., Illangasekare, T.H.: Permeability determination for unsaturated soils. In: Unsaturated Soils, pp. 163–174. ASCE (1993)Google Scholar
  3. Benson, C.H., Gribb, M.M.: Measuring unsaturated hydraulic conductivity in the laboratory and field. Geotech. Spec. Publ. 68, 113–168 (1997)Google Scholar
  4. Crescimanno, G., Iovino, M.: Parameter estimation by inverse method based on one-step and multi-step outflow experiments. Geoderma 68(4), 257–277 (1995)CrossRefGoogle Scholar
  5. Elzeftawy, A., Mansell, R.S.: Hydraulic conductivity calculations for unsaturated steady-state and transient-state flow in sand. Soil Sci. Soc. Am. J. 39(4), 599–603 (1975)CrossRefGoogle Scholar
  6. Figueras, J., Gribb, M.M., McNamara, J.P.: Design of a new automated multi-step outflow test apparatus. In: AGU Fall Meeting. AGU Fall Meeting Abstracts (2006)Google Scholar
  7. Gardner, W.R.: Calculation of capillary conductivity from pressure plate outflow data. Soil Sci. Soc. Am. J. 20(3), 317–320 (1956)CrossRefGoogle Scholar
  8. Hwang, S., Powers, S.E.: Using a multi-step outflow technique to estimate unsaturated hydraulic conductivity function for quartz sands with variable interfacial properties. American Geophysical Union (2001)Google Scholar
  9. Kunze, R.J., Kirkham, D.: Simplified accounting for membrane impedance in capillary conductivity determinations. Soil Sci. Soc. Am. J. 26(5), 421–426 (1962)CrossRefGoogle Scholar
  10. Kool, J.B., Parker, J.C., Van Genuchten, M.T.: Determining soil hydraulic properties from one-step outflow experiments by parameter estimation: I. Theory and numerical studies. Soil Sci. Soc. Am. J. 49(6), 1348–1354 (1985)CrossRefGoogle Scholar
  11. Klute, A.: The determination of the hydraulic conductivity and diffusivity of unsaturated soils1. Soil Sci. 113(4), 264–276 (1972)CrossRefGoogle Scholar
  12. Miller, E.E., Elrick, D.E.: Dynamic determination of capillary conductivity extended for non-negligible membrane impedance1. Soil Sci. Soc. Am. J. 22(6), 483–486 (1958)CrossRefGoogle Scholar
  13. Meerdink, J.S., Benson, C.H., Khire, M.V.: Unsaturated hydraulic conductivity of two compacted barrier soils. J. Geotech. Eng. 122(7), 565–576 (1996)CrossRefGoogle Scholar
  14. Parks, J.M., Stewart, M.A., McCartney, J.S.: Validation of a centrifuge permeameter for investigation of transient infiltration and drainage flow processes in unsaturated soils. ASTM Geotech. Test. J 35(1), 182–192 (2012)Google Scholar
  15. Rijtema, P.E.: Calculation of capillary conductivity from pressure plate outflow data with nonnegligible membrane impedance. Institute for Land and Water Management Research (1959)Google Scholar
  16. Raimbault, G.: Diffusivite et conductivite hydrauliques de materiaux ou sols non satures en eau - mesure en laboratoire. Bull. Liaison Lab. Ponts Chauss 145, 61–68 (1986)Google Scholar
  17. Shao, L.T., Wen, T.D., Guo, X.X., Sun, X.: A method for directly measuring the hydraulic conductivity of unsaturated soil. Geotech. Test. J. 40(6), 20160197 (2017)CrossRefGoogle Scholar
  18. van Dam, J.C.: Inverse method to determine soil hydraulic functions from multi-step outflow experiments. Soil Sci. Soc. Am. J. 58(3), 647–652 (1994)CrossRefGoogle Scholar
  19. van Genuchten, M.T.: A closed-form equation for predicting the hydraulic conductivity of unsaturated soils. Soil Sci. Soc. Am. J. 44(5), 892–898 (1980)CrossRefGoogle Scholar
  20. Vanapalli, S.K., Garga, V.K., Brisson, P.: A modified permeameter for determination of unsaturated coefficient of permeability. Geotech. Geol. Eng. 25(2), 191–202 (2007)CrossRefGoogle Scholar
  21. Znidarcic, D., Mccartney, J.S.: Testing system for hydraulic properties of unsaturated nonwoven geotextiles. Geosynth. Int. 17(5), 355–363 (2010)CrossRefGoogle Scholar
  22. Znidarcic, D., Hwang, C. Bicalho, K. V.: Experimental determination of hydraulic characteristics for unsaturated soils. In: Juca, J.F.T., de Campos, T.M.P., Marinho, F.A.M. (eds.) Proceedings of the 3rd International Conference on Unsaturated Soils, vol. 3, pp. 1137–1141. Swets & Zeitlinger, Lisse (2002)Google Scholar
  23. Zornberg, J.G., McCartney, J.S.: Centrifuge permeameter for unsaturated soils I: theory and experimental philosophy. ASCE J. Geotech. Geoenviron. Eng. 136(8), 1051–1063 (2010)CrossRefGoogle Scholar

Copyright information

© Springer Nature Singapore Pte Ltd. 2018

Authors and Affiliations

  1. 1.State Key Laboratory of Structural Analysis for Industrial EquipmentDalian University of TechnologyDalianChina
  2. 2.Department of Engineering MechanicsDalian University of TechnologyDalianChina

Personalised recommendations