5" bored hole on floor

[kenanleung]

In an office building floor, my client proposes to put 4 full size (36"x18") filing cabinets side by side where there is a 5" bored hole through the floor approx. 12" behind the cabinets. the floor is 4" wire mesh reinforced concrete on 1.5" metal deck. It is rated at 50 psf LL + 50 psf DL + 20 psf Partition Load. The landlord is afraid of the bored hole will compromise the capacity of the floor. Will it?

 

[jayrod12]

Perhaps you should run the loads and check it out. If you're asking such a question without a sketch showing location of supports, location of loads, type of floor construction, then don't expect a real answer.

 

[XR250]

I doubt the hole will but the file cabinets might.

 

[kenanleung]

Thanks for the replies. Here is a sketch of the arrangement.

The black rectangle represents the 5" hole. The center of it is approx. 15" from the file cabinets on the left.

 

[JAE]

I agree with jayrod. Do an analysis of the affected structural elements and find out.

Not sure how you expect us to tell you with a floor plan sketch like that.

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[jayrod12]

We have still not been provided enough information. I assume with it being 4" concrete on metal deck that you have equally spaced joists below. What's this spacing, how far do the joists span, where are the beams, etc.

Honestly as XR indicated, the hole itself is likely not an issue, the issue is that we bet the filing cabinets overload the floor capacity.

 

[MER3]

36"x18" = 648sq. in or 4.5 sq. ft. At 50psf LL, you have an allowance for 4.5(50)=225 lb per file cabinet. Do you expect the file cabinet to weigh more than this? Do you expect people to stand or find other ways to occupy the same foot print, thus adding to the loading over the affected area? Is this location close to a main girder, or midspan of some lightweight joists?

 

[dik]

A little caution... I've encountered filing cabinet loads in excess of the design floor live load. Those suckers can get heavy pretty quickly.

Dik

 

[SwinnyGG]

Per AISC, paper weight is 58 lbs per cubic foot.

If this cabinet is 36" x 18" by 72" (I have a five drawer cabinet at home, and it's 72" tall, your height may vary) its actual 'consumable' volume inside is about 32" x 17.5" x 65"

Using those values, fully loaded, a five-drawer file cabinet could weigh 1,220 lbs.

That's almost 275 psf.