Are CBUSH elements compatible with NLSTAT analysis in OptiStruct?

Martina Blazheska

Hi, I am trying to find out if CBUSH elements are compatible in NLSTAT analysis.

From attending the lectures for OptiStruct for Non-Linear Analysis by Altair, I have found out that CBUSH1D elements are indeed compatible. What about CBUSH elements? I want to find out if I can reuse an already existing model which I built for a certain linear analysis (that incorporates CBUSH elements) in a non-linear one. 

Also, if anyone could provide a resource where I can check this for other elements as well, it would be very helpful. 

Adriano_Koga

Hi,

 

Sure. CBUSH and CBUSH1D are both available for NLSTAT.

But if you just provide the stiffness of each DOF, it will act as a linear spring/bushing.

If you want it to have a NL behavior, you should add a force x disp curve for the intended DOFs, using the KN options for the PBUSH.

Take a look at the help for PBUSHT, for more info.

Adriano_Koga

Hi,

 

Sure. CBUSH and CBUSH1D are both available for NLSTAT.

But if you just provide the stiffness of each DOF, it will act as a linear spring/bushing.

If you want it to have a NL behavior, you should add a force x disp curve for the intended DOFs, using the KN options for the PBUSH.

Take a look at the help for PBUSHT, for more info.

Martina Blazheska

Adriano A. Koga_21884 said:

Hi,

 

Sure. CBUSH and CBUSH1D are both available for NLSTAT.

But if you just provide the stiffness of each DOF, it will act as a linear spring/bushing.

If you want it to have a NL behavior, you should add a force x disp curve for the intended DOFs, using the KN options for the PBUSH.

Take a look at the help for PBUSHT, for more info.

Thanks for the super quick response!

viniciusgomes

Hello Martina, 

Please also refer to this article for more details: https://community.altair.com/csm/en/how-to-model-non-linear-spring-in-optistruct?id=kb_article&sys_id=021d0ee81bfbad10c4dfdbd9dc4bcb01

Thanks