Autodesk Robot Structural Analysis

[#1]

Hi,

Attached is a printout of my calculations and the model. As you can see the von Mises ratio is 2.86>1.0 (yellow mark in detailed analysis). My question is if Robot uses the maximum values the normal stresses and maximum values for shear stress? Or if Robot picks a critical point and then calculate the actual stress distribution in that specific point? I found it strange that I have a rather low member stability ratio of 0.6>1.0 but when I  do a deatiled analysis the von Mises criteria is exceeded. The steel quality is S355. Are the two sigma.X.Ed the normal stresses in the detailed analysis the stresses in the upper and lower flange? Do you have some document I can read about the theory robot uses regarding this issue?

Regards,

Anders

[#2]

The local effects of concentrated forces are disregarded for the 'global' check of the profile capacity It is assumed that either stiffeners are not needed or their sufficient number will be provided). Please mind that the results of the detailed verification depend on the area on which the force is applied and this can be set in the detailed analysis parameters dialog (bearing ss value on the Forces tab).

If you find your post answered press the Accept as Solution button please. This will help other users to find solutions much faster. Thank you.

[#3]

thank you. One quick question, is the length (bearing ss) measured along the length of the beam or transversal, meaning along the width of the beam?

Regards,

Anders

[#4]

Along the length.