Explain Live Load 1

[EIT2]

I was amazed when a "construction-related" individual was serious when asking, "If your floor framing plan specifies the allowable live load to be 100 psf, and I weigh over 200 pounds, if I should stand in a one square foot area, why do I not go through the floor?"

Since he was familiar enough with construction, I was still able to satisfy his curiousity with a technical exlanation. But, to the client or anyone else who seriously has'nt a clue, in as few words as possible, without any technical, structural jargon, what would be your "simple" explanation?

 

[DaveAtkins]

100 psf is a UNIFORM live load, across the entire floor, that is required by Code for certain occupancies. The Code also requires the floor to support a CONCENTRATED load equal to 1000 - 2000 pounds or more, depending on the occupancy.

DaveAtkins

 

[jike]

The 100 psf live load describes the (bending and shear)load capacity over the entire floor, not the (bearing or punching) load capacity of the floor under the contact of a person's feet. As a result, a person standing on the floor is supported (in bending and shear) by a much larger area than just the contact area of his feet. The bearing or punching condition is not normally a problem (since the bearing and punching capacity is much, much higher than 100 psf), even for women in high heels, on a concrete floor.

I have heard of a case, where the wheels of a fork truck punched thru a 4" slab. This is the only case where I can think that the punching might be be an issue, but who is crazy enough to drive on a 4" slab, which never was intended for fork trucks?

 

[Focht3]

Warehouse managers.



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