Slab-beam connection?

[drile007]

1) I model a beam under the slab in Etabs. What kind of connection does Etabs presume between them, rigid or no connection at all?
2) How can I "tell" Etabs that the beam is under or above slab? I need this info. for exporting the exact model to Safe (or I can't do this in Etabs, but I can correct the vertical position in Safe).

Drile007

 

[slickdeals]

You can specify the location of the beam by using the "specity frame insertion point" By default ETABS places the top of the beam at the center of the slab. You can change this by changing your insertion point. And I think ETABS assumes a rigid connection between the beam and slab. I know it assumes composite action in case of a steel beam and concrete slab.

 

[ASCE07]

Remember that ETABS transfers the loads only at the end points of elements.

You need to provide as many segments to beam and slab (meshing) in order to achieve near uniform/accurate mass distribution in the model.I would recommend at least three divisions on each elements.If you do not segment slab and beams load from slab will directly pass to columns, thus you will get a beam under designed.

Connections will be "rigid" (although this is not a connection a tall, the RC structure are monolithic)

hope that helps.

 

[TSReddy]

Mr.ASCE07
"ETABS converts the object based model into element based model for analysis and results are reported back on the object based model". If this statement is true, then what is the necessity of doing many segments to beams and slabs?
As per my knowledge ETABS can do this process internally and no need of segments.

 

[amadeus]

If the slab has been defined as SHELL then meshing it will be necessary for the correct transfer of vertical loads. A minumum of three segments per side is often enough mesh refinement. If the slab has been defined as MEMBRANE you won't have to mesh it. The beams DO NOT need to be segmented in order to achieve correct load transfer.