Question

According to Bredt--Batho theory, shear flow in a thin-walled closed section under torsion is

• A. Zero at corners
• B. Varies linearly along perimeter
• C. Constant along the wall
• D. Maximum at centroid

Hint:

For a thin-walled closed section, \[ \boxed{ q=\frac{T}{2A_m} } \] where \[ q \] is the constant shear flow around the section.

Answer 1

The Correct Option is C

Step 1: Recall the Bredt--Batho theory. For a thin-walled closed section subjected to torsion, the Bredt--Batho theory states that the shear flow is uniform around the wall.

Step 2: State the shear flow relation. The shear flow is given by \[ \boxed{ q=\frac{T}{2A_m}, } \] where
• \(T\) = applied torque,
• \(A_m\) = area enclosed by the median line. Since \[ q \] does not depend on the position along the wall, \[ \boxed{ \text{Shear flow remains constant around the wall.} } \] Therefore, \[ \boxed{(C)} \] is the correct answer.