A sand specimen is isotropically consolidated in a triaxial test apparatus to 420 kPa and then...

A sand specimen is isotropically consolidated in a triaxial test apparatus to 420 kPa and then sheared with the drainage valves open (i.e., an S or CD test). At failure, (σ1 – σ3) is 1046 kPa. Determine the major and minor principal stresses at failure and the effective internal friction angle (assume c' = 0). Plot the Mohr diagram. (Problem originally from Holtz and Kovacs, 11-10)

Another specimen of the same sand as in Problem 1 (i.e., same f' and c') is tested in a direct shear apparatus under a normal pressure of 420 kPa. The sample fails when a shear stress of 280 kPa is reached. Determine the major and minor principal stresses at failure. Plot the Mohr diagram. (Problem originally from Holtz and Kovacs, 11-11)

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Ally Wells answered 4 months ago

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