Parking Garage - traditional reinforced CIP flat plate w/ composite steel beams

[gregroberson]

Does anyone have any insight to designing a steel-framed open deck parking garage using composite steel beams with a traditional reinforced CIP flat plate (no post tensioning).

Our customer would like a steel and CIP solution. However, he would like to not deal with the possible maintenance associated metal deck and the possability of rusting. Additionally, he does not want a post tensioned slab.

AISC Design Guide 18 list numerous configurations, reinfoced flat plate & composite beam design is not listed. The only specifically mentiong tensioning and CIP over metal deck.

Any thoughts or direction to additional materials would be very appreciated.

Greg Roberson | E.I.T.

 

[slickdeals]

You may want to look at GirderSlab system

http://www.modernsteel.com/Uploads/Issues/February_2012/022012_flat_plate.pdf

http://www.girder-slab.com/

 

[steellion]

The owner is worried about rusting of the steel deck but not the steel beams? This system can be done, but I doubt it would be the most efficient. Why not an all cast-in-place concrete system?

 

[gregroberson]

Our potential client is a steel fabricator and erector. . . vested intrest in steel. Additionally, they have a large quantity of steel already on hand that they are hoping to efficiently use into design. . .thus,the girder slab system wouldn't fit for them. Thanks you for the replys so far.

Are there any major comparable inefficiencies with the flat slab system if it is properly designed? Or any major pitfalls that are not appearant that you are aware of.

Greg

 

[PMR06]

Will you need fire protection for the steel?

Here's an interesting article discussing fire protection:

http://www.modernsteel.com/Uploads/Issues/April_2010/042010_Apr10_fire_NASCC_web.pdf

 

[TXStructural]

I would shy away from composite beams, since the composite studs will be vulnerable to corrosion, and loss of composite action is likely over time. Properly constructed, in some climates, flat slab on a steel frame will work just fine. Be sure you design and require construction to minimized cracking (do not excessively minimize slab thickness; pay careful attention to deflection of steel members; avoid concrete which develops high early strength, has high shrinkage, or uses aggregates subject to excessive thermal expansion; isolate columns and detail reinforcement to control reentrant cracking, and use additional top reinforcing across stiff members to control negative moment cracks across beams.)
Consider galvanizing the frame if you are near a coast or where roads are salted.

 

[hokie66]

Use this system only if there is going to be an effective membrane. Also design the slab with reinforcement similar to that in a water retaining structure, about 0.6% Ag. And the frame should either be galvanized or have a high performance coating system.