Civil Engineering - Strength of Materials - Discussion

When a rectangular beam is subjected to longitudinal loading (like bending due to transverse loads) , shear stress is developed within the material.

When a beam bends, top fibres compress, bottom fibres stretch (tension), whereas the Internal layers (fibres) slide relative to each other.

This sliding tendency is resisted by internal shear stress. This shear stress acts horizontally between all the layers between top and bottom fibres giving a parabolic shear distribution.

The shear stress varies along the depth of the beam and it Is maximum at the neutral axis, and zero at the extreme fibres.

The shear stress follows a parabolic distribution across the height of the rectangle, with its peak at the centre (neutral axis) and tapering to zero at the top and bottom surfaces.

@Anand.

i.e 4 for shear developed due to bending. In question,here it is asked due to axial load or longitudinal load. So the answer is D.

Well said, thanks @Anand.

For rectangular beams shear stress is parabolic as zero at ends and maximum at NA so every horizontal plane having some shear stress.

Every horizontal or vertical it would be?

How? Explain.