Using the graphical method, determine the following for the soil element shown below: $($a$)$ major and minor principal stresses; $($b$)$ normal and shear stresses on plane AB$.$

$3$ for the element shown in Figure $10\mathrm{.}36.$

own in Figure $10\mathrm{.}37.$ Using the pole method, determine:

inimum principal stresses

r stresses on plane $AB$

$5$ for the element shown in Figure $10\mathrm{.}38.$

A sample of dry cohesionless silt is tested in a direct shear test. At failure, the vertical normal stress is $80$kPa and the shear stress on the horizontal plane where failure occurs is equal to $40$kPa. Using the graphical method. determine the