Question

me that both a triaxial shear test and a direct shear test were performed on a sample of dry sand. When the triaxial test is performed, the specimen was observed to fail when the major and minor principal stresses were 100 lb/in2 and 20 lb/in2, respectively. When the direct shear test is performed, what shear strength can be expected if the normal stress is 3000 lb/ft2

Answer 1

shear strength = 2682.31 Ib/ft^2

Step-by-step explanation:

major principal stress = 100 Ib / in2

minor principal stress = 20 Ib/in2

Normal stress = 3000 Ib/ft2

Determine the shear strength when direct shear test is performed

To resolve this we will apply the coulomb failure criteria relationship between major and minor principal stress a

for direct shear test

use Mohr Coulomb criteria relation between normal stress and shear stress

Shear strength when normal strength is 3000 Ib/ft = 2682.31 Ib/ft^2

attached below is the detailed solution