LL reduction - foundations - need references

[sr12]

I'm designing a building using LL reduction for a LL greater than 100 psf - IBC 2000 1607.9.2. Someone reviewing the calculations for the client has said that note #2 allows for the reduction in the column loads, but since it only specifically says "columns", LL reduction does not apply to the foundation design. How can I get this person to understand that the column reactions ARE the foundation loads? It's common sense, but I haven't found a specific statement anywhere that says it. I need this reviewer's approval and since he has already convinced himself that this statement excludes foundations, I need something in print to convince him otherwise. Thanks.

 

[linslade]

The British Standard for live loads (BS 6399 Part 1) specifically states that the floor live load reduction also applies to "the design of columns, piers, walls and their supports and foundations".

Perhaps you could use this to persuade your reviewing engineer that it is not unreasonable for you to take account of the load reduction in your foundation design.

linslade

 

[TFL]

i just looked in the 2000 ibc structural handbook. it does not really help your case. it simply explains that live load reduction is contrived to produce structural members such that if the full load was seen by the member it would only be 30% overstressed. a 30% overstress in a column is ok. i would asssume that any structural foundation could also handle a 30% overstress. i would only then worry about the soil preassures if i had bad soils

 

[JAE]

Nothing in the code body itself that I see...perhaps a call to ICC?

 

[Focht3]

How about a letter from the Geotechnical Engineer of Record?



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