Tension bending stress in U-beam
The simply supported beam has an overhang from B to C. This configuration will produce a positive bending moment in some portions of the span and a negative bending moment in others. The shear-force and bending-moment diagrams for the beam will be drawn to determine the most critical bending moments.
The beam cross section is not symmetrical about a horizontal axis z. Consequently, the centroid location must be determined. Once the centroid is located, the moment of inertia of the cross section about this centroidal axis must be computed.

Once the largest moments and the section properties are known, the flexure formula will be used to compute bending stresses at the critical locations.

Tension bending stress in U-beam