For a shear vane of height H and diameter D, show that the shear strength Cu is related to the torque T by: T Cu D п. D2 A shear vane of height 150 mm and diameter 50 mm was used to measure the strength of a saturated clay. If the required torque on the vane to cause failure of the clay was 42.24 Nm, calculate the undrained shear strength of the soil. The vane was then rotated rapidly through 25 revolutions to completely remould the clay and torque of 16.9 Nm was needed to shear it. What was the sensitivity of the clay? A further test at the same depth in the same clay layer was carried out using a vane with D = 50 mm and H= 50 mm. If the measured torque was 19.7 Nm, calculate Cu in the horizontal and vertical planes, and the ratio of these strengths. T = nD²(Cuv. H/2+ Cur.º76)

For a shear vane of height H and diameter D, show that the shear strength Cu is related to the torque T by: T Cu D п. D2 A shear vane of height 150 mm and diameter 50 mm was used to measure the strength of a saturated clay. If the required torque on the vane to cause failure of the clay was 42.24 Nm, calculate the undrained shear strength of the soil. The vane was then rotated rapidly through 25 revolutions to completely remould the clay and torque of 16.9 Nm was needed to shear it. What was the sensitivity of the clay? A further test at the same depth in the same clay layer was carried out using a vane with D = 50 mm and H= 50 mm. If the measured torque was 19.7 Nm, calculate Cu in the horizontal and vertical planes, and the ratio of these strengths. T = nD²(Cuv. H/2+ Cur.º76)