Question

1. (a) Briefly explain Mohr-Coulomb theory and show how we can determine the shear strength parameters of soil by plotting the shear stress versus normal stress.

    [3 marks]

2. The following results were obtained from a consolidated undrained Triaxial (CU) test with pore water pressure measurement on three samples of a fully saturated clay. Determine the total (undrained) stress and effective (drained) stress parameters.  

[12 marks]

Sample	Cell pressure (kN/m2)	Deviator stress at failure (kN/m2)	Pore pressure at failure   (kN/m2)
A	300	326	146
B	400	416	206
C	600	635	208

Answer 1

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Julia 3= ssil .T3 Cell prossure Mass 11 11 گیا Coul prosswo All Round the soil deviator Stress load Appliedon soil aftor making acell prossuone Constant. TT 1,0,fra ITE T34 Td Case] Ju budrained Condition Mans drainage not allowed, so Pore water pressure Generated, Honce we consider Elective stress paramotor - T = Jst od Ba 400 2063 300 -146= 154 Ko/M2 (13)8 194 kN/m2 (53), 600 - 208= 392ku/M2 (Tila = Islat (Jula 1544326 (51) B= 1944416 610 kN/m2 Gile 392 +635 1027 KW/m2 480 kolme

We know that 1, = Tij ataw? (ust ) +2e tom (USA) for Clay sal = 0° Ti J3 4 20 20 = 5-63 C - Apprant Colosion of soll in Kalma (- Ti-63 2 CA 4801 154 2 163 kolme CB = Glor igy 2 208 Kolm? 2111 С, 1027-292 = 31%05 Kalma l