Steel Design Error

[finalfunk]

I have modelled a very large bridge in 3D using hundreds of custom sections. After applying loads and defining boundary conditions etc, I ran a Steel Design Check of Struture to find members that were overstressed.

In most of the bridge, my members were fine (less than 50% stress/resistance), however in some of my members, they were registering as overstressed. When I viewed the details for any given member is argued that "B1 is undefined" and will not give meaningful results that tall me what to adjust.

Can you tell me whats wrong? Is it a problem due to custom sections, or something else?

Thanks.

 

[stressed]

B1 is needed for some codes in order to do stability analysis checks. You'll have to determine B yourself and "assign" these design parameter values using Design menu>Steel frame design>View/Revise overwrites.

As an aside, I'm curious, does your version of SAP have bridge design codes now for steel design? My version says AASHTO Steel 04, but I couldn't find much info or documentation on it, so I just assumed that it wasn't a very comprehensive implementation. Let us know how it works out for you.