10-24. In a direct shear test on a specimen of cohesionless sand, the vertical normal stress on the specimen is 300 kN/m2 and the horizontal shear stress at failure is 200 kN/m². (a) Assuming uniform stress distribution within the failure zone and a straight line failure envelope which goes through the origin, determine by means of the Mohr circle the magnitude and direction of the principal stresses at failure. (b) Explain why it is not possible to determine the principal stresses in a direct shear specimen for an applied horizontal shear stress which is not large enough to cause failure. (After A. Casagrande.)

10-24. In a direct shear test on a specimen of cohesionless sand, the vertical normal stress on the specimen is 300 kN/m2 and the horizontal shear stress at failure is 200 kN/m². (a) Assuming uniform stress distribution within the failure zone and a straight line failure envelope which goes through the origin, determine by means of the Mohr circle the magnitude and direction of the principal stresses at failure. (b) Explain why it is not possible to determine the principal stresses in a direct shear specimen for an applied horizontal shear stress which is not large enough to cause failure. (After A. Casagrande.)

Principles of Foundation Engineering (MindTap Course List)

8th Edition

ISBN:9781305081550

Author:Braja M. Das

Publisher:Braja M. Das

Chapter2: Geotechnical Properties Of Soil

Section: Chapter Questions

Problem 2.22P

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