Question

1. A series of four consolidated undrained triaxial tests with pore pressure measurement gave the fol- lowing results for a saturated clay. test # confining stress σ3 (kPa) initial pore pressure uo (kPa) deviator stress at failure (σ1-03)(kPa) pore pressure at failure ur (kPa) #1 #2 #3 #4 150 300 450 600 0 202 0 305 0 410 103 82 169 252 331 (a) Determine c' and φ' for this material. HINT: estimate a, and α, for the Kf line and then convert to c' and φ". Calculate the Skempton A parameter at failure for each test where A-(Au)/do,-Δυ/(σ1-o). A sample of this soil is initially consolidated under an all-round pressure ơ,-300 kPa and initial pore pressure u。-0 (same as test #2). The drain is then closed. The all-round pressure σ3 is then changed to 350 kPa. If an axial stress is applied, what would be the expected principal stress dif- ference ơ1-03 at failure? HINT: what is the initial effective confining stress at the start of shear? (b) (c)

For 1 a) c’=0 & angle = 25.6 degrees

dont answer if u didnt get that. and show ur work please

Answer 1

Text So 3oo 600 Lt Ckfa)826gS2 33/ Vi(Ma) 253-502. 7SS loto So367 17 3 03-68 13/ 98 369 63 98-13 5759 う0-25-1S

Takicg average 102 202 30s HtO 76. 0.837 0826 0.807 gus