Solid vs. shell element in ABAQUS

[hrtuwair]

Dear All,

I modeled a sandwich panel in ABAQUS. The pane thickness is 4.15 inch and the facing's thickness is 0.09 in. I modeled the core and facings using solid elements (C3DR) and results were in good agreement with experimental results.
However, I am wondering is there a good arrgument to support my assumption that solid elements can be used to model the facing instead of using shell elements. I know that solid elements would require longer time to run as lots of elements are needed to maintain the aspect ratio in 3D direction. But since the work is already done and don't want to redo it to my client, your input would be appreciated.

Thanks!

 

[ESPcomposites]

It will depend on what you trying to achieve. "Good agreement with experimental results" is vague since we don't know what results you are trying to predict and correlate.

If you are only interested in the effects of in-plane stiffness for the facesheets, then solids would probably be fine (provided you can model it is an effective quasi-isotropic or orthotropic material). Such a case would be for the overall sandwich bending stiffness where the core is relatively thick.

But if you were trying to capture certain facesheet failure modes (such as facesheet wrinking or intracell buckling) a solid would not capture that phenomenon very well. In other words, if you are concerned about the bending stiffness of the individual facesheet, a shell may be a better option. For those modes, you may also want to properly represent the [A], , [D] matrices. You can not do that with a solid.

Brian

http://www.espcomposites.com