Shear stresses in a beam section cause a displacement or sliding action on a plane normal to the axis of the beam. This is unlike the deflection resulting from bending in a beam.

Normally deflection due to shear in the usual beam is ignored because it represents a very small percentage of the entire deflection. The deflection due to shear increases linearly as the length of the beam increases, whereas the deflection due to bending increases very rapidly as a third power of the length of the beam. For this reason the deflection due to shear is not an important factor except for extremely short spans where deflection due to bending drops off to a very small value.

In Graitec Advance Design, the linear element type includes beam and specially a ‘short beam’. The difference between these two types is the ‘beam’ type ignore shear deflection while ‘short beam’ type take that into account.