Determining the Shear Strength of Unsaturated Silt

  • Shulin Sun
  • Huifang Xu
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 112)

Summary

In order to determine shear strength of fine-grained unsaturated soils, a new design of a shear box for a modified direct shear device is described where a desired matric suctions is added easily with a hanging column. Simple principles were employed to develop the direct shear testing device so that it would be robust, easy to use, and readily assembled and disassembled for testing and maintenance. Tests were conducted with sandy silts under several net normal stresses (σn ua) for different desired matric suction (ua–uw). The results show that unsaturated shear strength and friction angle (πb) is consistent with results from prediction procedure (Fredlund and Barbour 1996) and estimated friction angle (πb) based on a soil-water characteristic curve (SWCC) of the sandy silt, respectively.

Key Words

unsaturated soil matric suction direct shear shear strength shear box 
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References

  1. ASTM D 3080–03 (2003) Standard Test Method for Direct Shear Test of Soils Under Consolidated Drained Conditions, Annual Book of ASTM Standards, ASTMGoogle Scholar
  2. ASTM D 6836–03 (2004) Standard Test Methods for Determination of the Soil Water Characteristic Curve for Adsorption Using a Hanging Column, Pressure Extractor, Chilled Mirror Hygrometer, and/or Centrifuge, Annual Book of ASTM Standards, ASTMGoogle Scholar
  3. Abramento M, Carvalho CS (1989) Geotechnical Parameters for the Study of Natural Slopes Instabilization at ‘Serra do Mar’ Brazil. In: Proc 12th Int Conf Soil Mechanics and Foundations Engineering. Rio de Janeiro 3:1599–1602Google Scholar
  4. Bao CG, Gong B, Zan L (1998) Properties of Unsaturated Soils and Slope Stability of Expansive Soils, Key Note Lecture, UNSAT 98, 2nd Int Conf Unsaturated Soils, BeijingGoogle Scholar
  5. Escario V (1980) Suction controlled penetration and shear tests. In: Proc 4th Int Conf on Expansive ASCE Publication. Denver 2:781–797Google Scholar
  6. Escario V, Juca JFT (1989) Strength and deformation of partly saturated soils. In: Proc 12th Int Conf on Soil Mechanics and Foundation Engineering. A. A. Balkema, Bookfield, MA 2:43–46Google Scholar
  7. Escario V, Saez J (1986) The shear strength of partly saturated soils, Geotechnique 36(3):453–456Google Scholar
  8. Fredlund DG, Morgenstern NR, Widger RA (1978) The shear strength of unsaturated soils, Can Geotech J 15(3):313–321CrossRefGoogle Scholar
  9. Fredlund MD, Barbour SL (1996) The Relationship of the Unsaturated Soil Shear Strength Function to the Soil-Water Characteristic Curve, Can Geotech J 33(3):440–448Google Scholar
  10. Fredlund DG, Morgenstern NR (1977) Stress State Variables for Unsaturated Soils, ASCE J Geotech Eng Div 103(GT5):447–466Google Scholar
  11. Gan JKM, Fredlund DG, Rahardjo H (1988) Determination of the Shear Strength Parameters of an Unsaturated Soil Using the Direct Shear Test, Can Geotech J 25:500–510Google Scholar
  12. Ho DYF, Fredlund DG (1982) Increase in shear strength due to suction for two Hong Kong soils. In: Proc ASCE Geotech Conf, Engineering and Construction on Tropical and residual soils. Honolulu, Hawai, U.S.A., January 11–15 pp 263–295Google Scholar
  13. Khalili N, Khabbaz MH (1997) A unique relationship for χ for the determination of the shear strength of unsaturated soils, Geotechnique 48(5):681–687Google Scholar
  14. Nishimura T, Fredlund DG (2001) Failure envelope of a desiccated unsaturated silty soil. In: Proc 15th Int Conf Soil Mech Geotech Eng. Istanbul 1:615–618Google Scholar
  15. Oberg A-L, Sallfors G. (1997) Determination of shear strength parameters of unsaturated silts and sands based on the water retention curve, Geotech Test J 20:40–48CrossRefGoogle Scholar
  16. Rassam DW, Williams DJ (1999) A relationship describing the shear strength of unsaturated soils, Can Geotech J 36:363–368CrossRefGoogle Scholar
  17. Rohm SA, Vilar OM (1995) Shear strength of an unsaturated sandy soil. In: Alonso EE, Delage P (eds) Proc 1st Int Conf Unsaturated Soils. Paris 1:189–193Google Scholar
  18. Toll DG (1990) A framework for unsaturated soil behavior, Geotechnique 40(1):31–44CrossRefGoogle Scholar
  19. Vanapalli SK, Fredlund DG, Pufahl DE, Clifton AW (1996) Model for the prediction of shear strength with respect to soil suction, Can Geotech J 33(3):379–392Google Scholar
  20. Wang X, Benson CH (2004) Leak-free pressure plate extractor for measuring the soil water characteristic curve, Geotech Testing J 27(2):163–172Google Scholar
  21. Wang X, Benson CH (2003) Pressure Plate Extractor, United States Patent No. 6,718,835Google Scholar
  22. Wheerler SJ, Sivakumar V (1992) Development and application of a critical state model for unsaturated soils, In: Houlsby GT, Schofield AN (eds) Proc Wroth Mem Symp Predictive Soil Mechanics, ASCE, New York. OxfordGoogle Scholar

Copyright information

© Springer-Verlag 2007

Authors and Affiliations

  • Shulin Sun
    • 1
  • Huifang Xu
    • 2
  1. 1.Department of Geological and Geotechnical Engineering, College of Civil EngineeringHohai UniversityNanjingChina
  2. 2.Department of Geology and GeophysicsUniversity of Wisconsin-MadisonMadisonUSA

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