I) A sand sample was hydrostatically consolidated under 500 kPa cell pressure and 200 kPa pore pressure in a triaxial test device. Then it was sheared with the drainage valves open. At failure, axial stress (a1) was 1100 kPa. a. Draw the Mohr circle in effective stress space, and determine the angle of friction of the sand. b. A specimen of the same sand at the same density was also tested in a direct shear apparatus under a normal pressure of 420 kPa. Estimate the shear stress required to fail the specimen. Draw the Mohr circle at failure, and determine principle stresses.

I) A sand sample was hydrostatically consolidated under 500 kPa cell pressure and 200 kPa pore pressure in a triaxial test device. Then it was sheared with the drainage valves open. At failure, axial stress (a1) was 1100 kPa. a. Draw the Mohr circle in effective stress space, and determine the angle of friction of the sand. b. A specimen of the same sand at the same density was also tested in a direct shear apparatus under a normal pressure of 420 kPa. Estimate the shear stress required to fail the specimen. Draw the Mohr circle at failure, and determine principle stresses.

Principles of Geotechnical Engineering (MindTap Course List)

9th Edition

ISBN:9781305970939

Author:Braja M. Das, Khaled Sobhan

Publisher:Braja M. Das, Khaled Sobhan

Chapter12: Shear Strength Of Soil

Section: Chapter Questions

Problem 12.13P

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