Correct option is C
Correct Option: C
Given
The Vane Shear Test is used to determine the undrained shear strength of soft to medium cohesive soils. The test is conducted as per IS : 2720 (Part XXX) – 1980.
The vane consists of four thin rectangular blades mounted symmetrically on a central rod.
As per IS : 2720 (Part XXX) – 1980, each blade is fixed at an angle of (90^\circ) to the adjacent blade.
Therefore,
Angle between adjacent blades =90 degree
Hence, Option C is correct.
Additional Information
The standard vane used in the vane shear test has the following specifications:
| Parameter | Specification | ||
| Number of blades | 4 | ||
| Angle between adjacent blades |
| ||
| Shape of blades | Thin rectangular | ||
| Purpose | Determination of undrained shear strength of cohesive soils |
The vane is pushed into the soil and rotated at a uniform rate. The maximum torque required to cause failure is used to determine the undrained shear strength of the cohesive soil.
