Warehouse floor loading 1

[Dropout]

Hi All.

I'm in a Canadian military warehouse. The floor, support columns and roof seem to be one piece. The floor is 8 inches thick (at least in the place we drilled)

The building was built in 1951. I have most of the drawings but not the foundation ones.

How can I find out if there is re-bar in the floor?

What is a reasonable dead load I can put on the floor? I've been looking at pallet racking which puts 12,000 pounds on 4 small pads totaling 0.38 square feet. That works out to a 30,000 pound per square foot load which seems high yet I see it in every warehouse I go into.

Is compressive strength a good figure to base dead load estimates on? Shear?

Thanks in advance.

 

[dik]

What is the spacing of the legs? This has a big effect on the flexural stresses in the slab. What is the stiffness of the subsurface soil? also a big impact...

Dik

 

[csd72]

You can get someone in to do an x-ray analysis, this will cost no more than $1000 I expect.

With this they will give you a chart from which you can determine the spacing of the bars and the cover depth, but you only get a rough idea of bar size.

This will only be for a small sample though.

 

[csd72]

Here is an American link to the sort of thing I was talking about:

http://www.radar-solutions.com/html/slab.html

 

[golf39]

I would think you could use a "R" Meter or Pachometer to determine the rebar spacing & roughly estimate size, but taking core over the located rebar should be done to determine exact size. I would think this would be less expensive than x-raying etc.

 

[JAE]

Dropout - you need to simply hire a licensed structural engineer to look into this for you.

 

[Ron]

golf39 and JAE are both correct! Radiography of concrete slabs is expensive and specialized...it also requires access to both sides of the slab, so slabs on grade are out.

Magnetic location devices (R-meter, pachometer, FerroScan) are all legitimate methods of rebar location. Ground penetrating radar can be used, but in my experience is not as accurate due to interpretation errors.