How to solve

Results Analysis

Using the calibration card, find the Shear Strength of the soil in KPa.

Calculate the Torque required to shear $(M)$ in $Nm,$ from the equation:

$W=\frac{M}{K}$

where W is the shear strength of the soil $($in kPa $)$ and K is a constant depending on dimensions and shape of the vane.

Assuming the distribution of the shear strength is uniform across the ends and around the curved surface of a cylincier, then:

$K=D^2\frac{H}{2}(1+\frac{D}{3H}){10}^{-6}$

where $D$ is the overall width of vane measured to $0\mathrm{.}1$ mm $($in mm $)$ and $H$ is the height of vane measured to $0\mathrm{.}1$ mm $($in mm $).$