How to support a structure in only one direction

[Anonymous]

Thx for reading my post. Please see attached model. I would like to support the bottom surface og the footplate so that i can not move down in the -z direction but can only deflect upwards in the +z. This would mean that the footplate is only RESTRAINED for downwards deflection. This corresponds to the plate laying on a concrete block. How can add this kind of support?

Hope anyone can help

[jo2ny]

Very true and obvious 🙂 duuh!

A combination between a case (that stand alone gives incorrect results) with other cases provides correct results, that whas my concern; but you cleared it.

( I could be a little bit nosey and ask who/why does this happen, but I shouldn't go offtopic, so i'll ask this later)

THANKS AGAIN for your anwsers, very helpfull.

[Artur.Kosakowski]

If you mean why lateral load case does not converge then check it may happen that just overturns the model (all UZ+ supports are switched off as the model starts to rotate). In other words check where your neutral axis is located vs. the support arrangement.

[jo2ny]

I fixed the convergence problem using a combination between these two suggestions: http://forums.autodesk.com/t5/Autodesk-Robot-Structural/Nonlinear-analysis-Iteration/m-p/3385747/hig... http://forums.autodesk.com/t5/Autodesk-Robot-Structural/convergence/m-p/3469484/highlight/true#M5032 Now everything looks fine, the reactions are all positive or 0 for the UZ+ supports. Thanks, again for your support.