I was designing a structure with the BS5950 code, when I realized in something strange: in certain elements with open sections (HEB), the torsion was not checked in the Robot steel design module.
I made a small example, with a cantilever beam: length equal to 0.5meters and the section is HEB200. Applied load: distributed torsion equal to 50kN.m.
When comparing the design by the EN1993-1 (image 1) with the design made by BS5950 (image 2), I realize that the verification of the torsion force is not being carried in the BS5950 calculation.
There is some error which I can be doing, or the Robot does not verify the torsion in the BS5950 code?
Solved! Go to Solution.
The torsion verification is not included for BS5950.
You can check the values of torsional stress caused by tosional moment in the stresses table.
Ok. One doubt: I view the stress caused by torsional moment (stress tables - image 3) and compared with the stress analysis for bars also made in the Robot, and I can't find the same value of stress in the bar's section (image 4).
This is because the formulations used in each case are different? I have only one load case.
The value in the table is calculated with use of the approximated formula from “Theory of Elasticity” - Timoshenko, Goodier - McGraw-Hill, 1951
h - web height
ea - web thickness
es - flange thickness
b - flange width
Wx - torsional modulus (tmax=Mx/Wx)
Ix / max(ea,es)
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