Designing Lateral Beams

[rmedina1]

I've been modelling a steel frame building with moment connected beams acting as the lateral system. When I run the program with the auto select list and run a steel design, I get the largest member in the auto select list assigned to the lateral beams. I tried removing that member size from the list, and rerunning the analysis and design, only to get the next largest member. Checking the strength and deflection ratios of the member, I am well below the limit for failure.

Does anyone know why the program isn't designing the beams appropriately, is there something i need to check with the overwrites. Any help would be greatly appreciated.

 

[ryansteel]

Hi there, I think when u use Autoselection in design the section that gets selected has something to do with the controls of drift/displacement of a jiont, and if no target drift specified it will select the section the gives smallest drift/displacement.

try this

http://www.csiberkeley.com/faq_ETABS.html#sfdo4