Slotted Steel Box Section Release

[umut.akparlar]

Hi,

I am trying to design a slotted steel structure but cannot decide which type of release to use. 

Those parts are pinned for the XY but released for Z direction. 

I designed the frame with RSA as follows:

I also defined a new release and applied for both slotted box sections: 

But when I perform analysis I am getting instability 2 type warning: 

Is there a way to design slotted type release with RSA? I tried to add a roller like support XY pinned and Z released still getting the same message. And it looks like there is movement along X even the X direction is not released. 

Thanks 

[Simau · Accepted solution]

Hi@umut.akparlar 

Try this

[umut.akparlar]

Thank you for your answer @Simau . 

There will be no moment transfer between those two members so if I uncheck Rxyz it won't reflect the real model? 

[Simau]

@umut.akparlar 

According to the nestings in the image below, mx my and mz bending moment will be transfered

[umut.akparlar]

That makes sense, thank you @Simau . 

Do you also think compatible node between those members also work?

Or nonlinear hinges ? 

Thanks 

[Simau]

@umut.akparlar 

Yes, it is possible to test the options you propose, but IMHO more complicated to apply.