An undisturbed soil sample, 110 mm in diameter and 220 mm in height, was tested in a triaxial machine. The sample sheared under an additional axial load of 3.35 kN with a vertical deformation of 21 mm. The failure plane was inclined at 50˚ to the horizontal and the cell pressure was 300 kN/m2 . i. Draw the Mohr circle diagram representing the above stress conditions, and from it determine: − Coulomb’s equation for the shear strength of the soil, in terms of total stress; − the magnitude and obliquity of the resultant stress on the failure plane.

An undisturbed soil sample, 110 mm in diameter and 220 mm in height, was tested in a triaxial machine. The sample sheared under an additional axial load of 3.35 kN with a vertical deformation of 21 mm. The failure plane was inclined at 50˚ to the horizontal and the cell pressure was 300 kN/m2 . i. Draw the Mohr circle diagram representing the above stress conditions, and from it determine: − Coulomb’s equation for the shear strength of the soil, in terms of total stress; − the magnitude and obliquity of the resultant stress on the failure plane.

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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An undisturbed soil sample, 110 mm in diameter and 220 mm in height, was tested in a triaxial machine. The sample sheared under an additional axial load of 3.35 kN with a vertical deformation of 21 mm. The failure plane was inclined at 50˚ to the horizontal and the cell pressure was 300 kN/m2. i. Draw the Mohr circle diagram representing the above stress conditions, and from it determine: − Coulomb’s equation for the shear strength of the soil, in terms of total stress; − the magnitude and obliquity of the resultant stress on the failure plane
Wo: Shear Strength 1 For a soil sample in a triaxial test, in a 120 kPa cell pressure, failure occurred in a normal stress of 450 kPa. If the cell pressure is 380 kPa, how much is deviator and major stresses? (p=0) (4 Marks)
An undisturbed soil sample, 110 mm in diameter and 220 mm in height, was tested in a triaxial machine. The sample sheared under an additional axial load of 3.35 kN with a vertical deformation of 21 mm. The failure plane was inclined at 50° to the horizontal and the cell pressure was 300 kN/m². i. Draw the Mohr circle diagram representing the above stress conditions, and from it determine: - Coulomb's equation for the shear strength of the soil, in terms of total stress; - the magnitude and obliquity of the resultant stress on the failure plane. ii. A further undisturbed sample of the soil was tested in a shear box under the same drainage conditions as used for the previous test. If the area of the box was 3600 mm? and the normal load was 500 N, what would you expect the failure stress to have been?
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