Data centre floor loading - raised access fl

[MIStructE_IRE]

Hi,

I have an existing data centre which has never had a raised access floor. The imposed load - 20kN/m sq, has always been applied directly to the floor slab. The floor slab comprises a concrete filled profiled composite metal deck.

The client is changing their cooling strategy and will now be adding a raised access floor. So the same load is still applied, but its now applied to the slab as a series of point loads on a 600mm x 600mm grid.

While the load is the same, so the moments and shear for a 1m strip should be the same in principle, or thereabouts, I’m looking for some degree of comfort regarding point loads on profiled composite slabs.

Has anyone any similar experience?

Thanks

 

[KootK]

1) On balance, I suspect that you'll be fine.

2) I would check punching shear for the point loads. The steel deck institute has some provisions for that.

3) Steel deck shear bond does not do super well with the local stresses caused by concentrated loads. Again, I think that you'll be fine for static loads spaced as tightly as you'll have them.

Questions:

4) how deep is your steel decking?

5) How much concrete do you have above the top of the deck?

6) What kind of deck spans are we talking about?

 

[MIStructE_IRE]

Thanks Koot,

My feeling is that its fine also once I check punching separately.

I’m at 2.8m spans and a 185mm deep concrete slab in an 80mm deep profiled metal deck.

 

[KootK]

Yeah, you can move a lot of point load through a 7" concrete slab. 9" and you can handle most fire trucks.

 

[MIStructE_IRE]

A fire truck is nothing compared to what some of these data centre guys looks for! I wouldn’t mind but anytime I see their cabinets they’re half empty..

 

[hokie66]

Agree with KootK. Slab designed for 20kPa loading will be fine for the access floor.

 

[MIStructE_IRE]

Thanks guys