Samples of a dry sand are to be tested in a direct shear test and a triaxial test. In the triaxial test, the sample fails when the major and minor principal stresses are 140 psi and 40 psi, respectively. What shear resistance is to be expected in the direct shear test when the normal load stress equals 5,000 psf?

Friction angle of dry sand is 35°. In a direct shear test on this sand, a normal stress of 150kPa was applied. What shear stress will cause the failure? (a) 150kPa (b) 50kPa (c) 78kPa (d) 105kPa

A series of unconsolidated undrained (UU) triaxial compression tests have been performed on two "identical" clay specimens. The test results are as follows: Test Number Confining Pressure (kPa)| Deviator Stress at Failure (kPa) 102 96 (i) (ii) 1 2 50 100 Plot the total stress Mohr circles for both specimens at failure (indicate the major and minor principal stresses on the plot). Draw the total stress Mohr-Coulomb failure envelop (i.e., the "p=0" envelop). Estimate the undrained shear strength.

Q18 Please provide justified answer asap