Machine-translated by Google. Questions are authored in English.
Top

Discussion

The maximum shear stress (τmax ) for a soil mass is equal to :

  • A.\((\sigma_{3} - \sigma_{1})/2\)
  • B.\((\sigma_{1} - \sigma_{3})/2\)
  • C.\((\sigma_{1} + \sigma_{3})/2\)
  • D.\((\sigma_{1} \times \sigma_{3})/2\)

Answer: B

The maximum shear stress is \((\sigma_{1} - \sigma_{3})/2\).

On Mohr's circle the major and minor principal stresses \(\sigma_1\) and \(\sigma_3\) mark the two ends of a diameter. The greatest shear stress is the radius of the circle, acting on planes at 45° to the principal planes:

\[ \tau_{max} = \frac{\sigma_1 - \sigma_3}{2} \]

\((\sigma_1 + \sigma_3)/2\) is the centre of the circle, the normal stress on the plane of maximum shear. \((\sigma_3 - \sigma_1)/2\) has the right size but is negative, and the product of the stresses has the wrong units.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.