Slab - twisting moments

[Anonymous]

Dear,

I need to model 3 type of 2-axis slab models in RSA 2014: drillfrei, drillweich and drillsteif (German terms). My German is not so good so I presume it has something to do with twisting moments of the slabs so it will be, i think: without twisting moments (drillfrei), with twisting moments but with the support uplift (drillweich), with twisting moments without support uplift (drillsteif). I have found some examples modeled in other software:

http://www.isa.fh-trier.de/home/Projekte/FEM_nicht_lineare_Lagerung_SB/ 

In folder Beispiel1--Berechnung mit RFEM (drillweich) and (drillsteif).

1. Has anyone met before with terms drillfrei, drillweich and drillsteif and am I correct connecting these with twisting moments?

2. If yes, is my assumption correct: 

                                   - drillfrei - I should model orthotropic slab leaned on 4 sides on pinned line supports, but with torsional stiffness = 0,00

                                   - drillweich - model simple slab leaned on 4 sides on pinned line supports, but with allowed uplift of the support UZ+

                                   - drillsteif - model simple slab leaned on 4 sides on pinned line supports

3. Am I making something wrong here about these slabs?

Thanks for Your time!

[Anonymous]

Can anyone answer or at least delete the post (because it is useless then)?

[Rafacascudo]

hace you even tried to do it??

I tried the 2nd one ,that with the uplift. It works with no problems

the 3rd one ,it will obviously work. Just set the pinned support for all sides.

the 1st one , don´t know if it is possible . Maybe the official support can tell you. Try experimenting with thickness/orthotropic/user-defined

[Anonymous]

Thanks for help. Yeah I have done the same as you. Drillfrei slab I modeled as orthotropic slab since i think these terms refer to drill moments, but I am not sure if it is correct.I will put comparision later on the forum.

[Anonymous]

can you show how do you define the analysis ? non linear? and how you set the support conditions? i am having problems with the convergence..

[Rafacascudo]

You don't have to set the analysis ,as it turns automatically into nonlinear as you create and assign a unidirectional support to a node.
For better convergence set it to update matrix after each iteration on nonlinear parameters

[Jummybear]

Once I was experimenting with r/c slab which with torsional stiffness = 0, but I get twisting moments anyway...