Question

In a uniform I-section beam, where does the largest shear stress act ?

• A. At any location in beam
• B. At Neutral axis
• C. At the top most layer in beam
• D. Shear stress is uniform throughout the cross section

Answer 1

Answer:

B. At Neutral axis

Shear stress in a uniform I-section beam is given by f = VQ / lb The intensity of shear stress is maximum at the centroid of the section, which is the neutral axis. For a symmetric I-section, the shear stress is zero at the extreme fibres. Therefore, the largest shear stress acts at the neutral axis.