Unexpected Moments at Beam End 2

[struceng99]

Hi, I have created an ETABS model but some of the results are coming out not quite as expected. I have pinned a couple of beam ends to check the behaviour, but even with pinned releases these beams still have a moment at their end (approximately 15 kNm). Does anyone know why this could be? Thanks.

 

[Nonlinearer]

When giving releases, support moment should be zero. Just double check you are checking at support face. For detailed comments, you may upload your ETABS file.

IR

 

[slickdeals]

Post the model.

It’s no trick to get the answers when you have all the data. The trick is to get the answers when you only have half the data and half that is wrong and you don’t know which half - LORD KELVIN

 

[PicoStruc]

Probably caused by joint offset or insertion point offset.

Check this documentation :

https://wiki.csiberkeley.com/display/tp/Effect+of+insertion+point+on+beam+reactions

 

[PicoStruc]

Explanation here : When you offset the beam centroid from the support, you create a hozitontal reaction at the support and then a negative moment in the "pinned" beam ends corresponding to the horizontal reaction and lever arm from the support to beam centroid.

That expected !

 

[struceng99]

Thank you! Yes, I had some joint offsets that were creating unexpected moments. Fixed now.