Following data are given for a direct shear test conducted on dry sand:
• Specimen dimensions: 63 mm X 63 mm X 25 mm (height)
• Normal stress: 105 kN/m2
• Shear force at failure: 300 N
a. Determine the angle of friction, Ø’
b. For a normal stress of 180 kN/m2 , what shear force is required to cause failure?
c. What are the principal stresses at failure for the condition given in (b)?
d. Locate the pole on this Mohr’s circle and find the angle of inclination of the major and minor principal plane with the horizontal?