The shear strength of a normally consolidated clay can be given by the equation f = '

Question:

The shear strength of a normally consolidated clay can be given by the equation τf = σ' tan 27°. Following are the results of a consolidated-undrained test on the clay.
• Chamber-confining pressure = 150 k N/m2
• Deviator stress at failure = 120 k N/m2
a. Determine the consolidated-undrained friction angle
b. Pore water pressure developed in the specimen at failure