Torsion design in beams

When it's torsion, you take your smallest dimension since the torsional stresses are equal around the perimeter of the cross section. at least that's how it was explained to me.

Hi anybody can give an example of torsion design of beam where breath is greater than depth, as shown in the picture above.
Since some of them still feel that bw is web width = 650 mm as per above figure.

As I said, a beam subjected to pure torsion (or essentially pure torsion when vertical loading is minimal) doesn't care whether it's vertical or horizontal, design procedure is the same for the torsion side of things.

I agree with Jayrod on all counts so far.

As we've discussed previously, however, I feel that strut and tie would be a better choice than sectional methods here based on your proportions.

I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.