Problem # 044

Unsymmetric Bending

A beam of length L= 2 m is fastened to a wall. Its cross-section is a square with height of 4 cm and width of 3 cm. The beam is subject to a single force P=5000 N at its free end. The force P is NOT aligned with the vertical, see angle α = 30 degree in the figure.


  1. Determine the internal moment in the beam directly at the wall due to the y-component of force P.

  2. Determine the internal moment in the beam directly at the wall due to the z-component of force P.

  3. Determine the moment of inertia of the square cross-section of the beam with respect to the z-axis.

  4. Determine the moment of inertia of the square cross-section of the beam with respect to the y-axis.

  5. Find the resulting flexure stress due to both internal moments at the 4 corner points A,B, C, and D of the cross-section where the beam enters the wall.