Torsional warping constant.For certain hat channel section, I can draw in section wizard and can obtain all values except Cw. How to manually calculate it.
A close example in a Mathcad 2000 worksheet, one U-lipped section (like a lift core without door headers). For open sections; change the geometrical coordinates in the input and you have one hat section. Below will include a pdf printout.
In the first site below, under
Beams -> Cross sections -> User defined -> Torsion: from dxf
there is a sheet for calculating torsional properties of any section defined by a drawing.
Roark has a formula for a hat section, not sure whether it is exactly what you are looking for.
The method of calculating Cw is given in "Cold-Formed Steel Structures" by Wei-Wen Yu. Expressions for hat sections and other cross sections are tabulated in Appendix B.
. I have not read the article, but it looks interesting. For hat channels, the article has the same formula as AISI's Cold-Formed Steel Design Manual 2008 edition.
to compute torsion, warping properties and related stresses, is really simple and efficient and for the price is really interessting it costs me only 99$. hope this helps. and good luck.
