Problem 3: Unconfined compression test was conducted on an undisturbed clay specimen. The test results are shown in the following table. Determine the undrained shear strength of the tested clay, taking into account the variation of changing sheared areas during test. Show detailed calculations. Table. Test results for a clay sample tested in unconfined compression apparatus Deformation Dial Gauge Reading (Div.) | Load Proving Ring Reading (Div.) 0 0 4 9 12 20 40 60 80 100 120 140 160 200 250 300 400 450 500 550 19 21 24 26 29 36 45 54 74 84 93 102/n400 450 500 550 600 650 700 800 900 950 1100 1200 1300 1400 1500 1700 1800 1900 84 93 102 112 120 129 144 160 166 182 192 202 209 217 229 234 240 243 250 253 2000 2200 2400 2600 255 2800 256 3000 254 Proving ring constant = 1.403 × 10³ kN/div; Specimen diameter = 7.3 cm Dial gauge constant = 0.01 mm/div

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