Shored or Unshored Composite Construction? 1

[abusementpark]

Do you generally design or specify shored or unshored composite steel construction? Obviously, each has its drawbacks.

Do you always do one opposed to the other? I'm curious what everyone's thoughts are.

 

[271828]

Yeah, I'm talking about composite steel beams with typical composite slabs. We included an extra inch of concrete to account for concrete over-run and cambered out 85% of the precomposite deflection. That really seemed to work well.

We cambered a few concrete beams, but we did not measure those.

 

[lkjh345]

Abusementpark:

Occasionally the precomposite load case governs. Just depends on the unique circumstances at each beam.

Similiar to 271828, we camber out 75% of the precomposite dead load. Seems to work out well.

We specifiy for the contractor to place a 'level floor' not a 'constant thickness' floor. Therefore, we assume an extra 1/2" of concrete in our load calcs to account for possible ponding of concrete.

I agree with 271828, you need to check composite steel framed floors for vibrations. You'll find yourself in trouble sooner or later if you don't. We also use FloorVibe for this. Very simple to use program, and can check typical bays in just a few minutes. Good protection against a whole lot of trouble.