Shear stress

- As mentioned previously,
**shear stress**is the type of stress that features**one plane sliding over another**. - Also mentioned before is that the effective area in calculating shear stress is PARALLEL to the external force.
- This makes the formula to calculate shear stress:

\begin{align} \sigma_s = \frac{L}{A_s} \end{align}

Where:

- $\sigma_s$ is the shear stress (Pa)
- $L$ is the external force/Load (N)
- $A_s$ is the shear area ($m^2$)

- Note that there are about 3 different ways shear stress can take place:
**Single shear stress**- This is the most simple of the shear stresses.
- For a situation like (1), the shear force would be acting on the cross sectional area of the bolt(blue).
- Thus, the shear area would be the bolt's CSA. Then simply apply the formula to calculate the shear stress.

**Double shear stress**- This is when a situation like (2) occurs.
- The shear force would still be acting on the CSA of the bolt, but it's on 2 different planes.
- Thus the shear area would be
**DOUBLE**the bolt's CSA.

**Punching shear stress**- This is a special case where the where the operation punches a hole in a plate
- In a case like (3), the shear stress in the plate acts on the hole's "edge" (blue)
- Thus, the shear area would be the
**perimeter of the hole multiplied by the thickness of the material.**

page revision: 1, last edited: 12 Jan 2011 09:08