What would be the proper choice between shell and frame for modelling 1.2m x 0.6m vertical element?

[ranawaseem]

What would be the proper choice between shell and frame for modelling 1.2m x 0.6m vertical element?

In a building I am studying expansion joints. All columns are 600mm dia circular. Except some vertical elements 1200x600mm.

1) The question is what system for seismic behaviour you would consider as per ASCE? shear wall or frame?

2) How would you model 1200x600 as frame or as shell?

 

[KootK]

Based on the information that you've provided, I'd call it a frame for ASCE. I'd probably model the 1200 columns as walls (shells). It's a judgement call but, at 4' or above, I feel that treating columns as true point supports is in appropriate.

The greatest trick that bond stress ever pulled was convincing the world it didn't exist.

 

[asixth]

For the lateral design I would consider it to be a frame unless you have a few stiff elements in there like a concrete core around a stair or lift.

For lateral modelling I think either a frame element or a shell element will give fairly similar results. I would model as a shell because that will give better slab coupling because the nodes will be at the edge of the column instead of at the centreline. May not have much impact on the results though.

 

[Thanh123]

In case of non_seismic, shell or frame is similar, provide the same EJ.
I remember when b>4h -> consider is wall, otherwise is column.
In case of seismic -> column is better, some softwares like Sap2000 automatically reduce EJ in seismic analysis for frame.