Question

A consolidated undrained (CU) triaxial compression test (TXC) was conducted on a specimen of saturated clay. The specimen was isotropically consolidated to a total cell pressure, σcell of 400 kPa. The backpressure was u0 = 100 kPa. At failure, the total pore water pressure was u = 90 kPa and the deviator stress was (σ1 − σ3)f = 526 kPa. Determine: a. The principal effective stresses, σ1′ and σ3′, at failure b. The friction angle, φ′ (secant method). c. The excess pwp, ue, at failure. d. Do you think this was an NC or an OC clay? Why?

Answer 1

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3 The. essuTe use 2 - 56-49- 5 p83-98

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