Decking/Mezzanine Rated Capacities

[klein5]

I have been assigned a project to "figure out" the loading of decking in my facility. Storage decks above the tool crib, work cells, etc. I've looked through OSHA and the Federal Code but could not find anything. Does anyone have any helpful suggestions?
All decking needs to be labeled with capacities such as a gross weight and or psi I believe.

Thanks,

Klein5

 

[boo1]

If it is:
Light storage warehouse space use 125 psf
Corridor space use 80 psf

 

[klein5]

Thanks Boo1, do you have any references for this?

 

[JAE]

klein5

What I understand as your task is to rate the load carrying capacity (live load capacity) of various mezzanine floors in your facility. Many times this is required of industrial firms due to insurance mandates or building code inspections.

What you must do is hire a structural engineer to do this for you as you cannot simply look up some reference as I'm sure all your mezzanines are different, with different spans, framing members, columns, etc.

If you have the original design plans of the floors in question, sometimes they provide critical information on how they were designed and constructed. This would be valuable information for your structural engineer as it might save a lot of design/research time.

The end result is that you would hire a licensed structural engineer to determine these floor capacities and you would then post these maximum live loads near each mezzanine floor area -

What boo1 correctly stated was that a "typical" live load requirement in most building codes for industrial mezzanines is 125 psf (this is classified as Light Storage). However, this is simply a code minimum requirement and is NOT necessarily what your floors possess.

 

[klein5]

So where is this spec? I understand the need/requirement to hire a structural engineer, but I need documentation. I looked on

http://www.access.gpo.gov/nara/cfr/cfr-table-search.html

the code of fed regs, i couldn't get to my search as there seem to be server issues...any other online refs?

thanks..

 

[JAE]

It's not a specification, but a building code requirement that various floor areas require a minimum live load capacity. You would need to contact your city building department and ask them which building code you are governed by...There are five possible codes in the U.S., each with various published editions:

Uniform Building Code
BOCA Code
Southern Standard Building Code
International Building Code (combination of the above three)
NFPA 5000 Code

Most all of these have identical live load requirements for different occupancies - in your case, minimum live load of 125 psf for light storage.

However, your floors, as they currently exist, may NOT have that level of live load capacity. This is where the structural engineer can determine what you have. Whether it is the 125 psf, or something less, you would post the true capacity of the floor, not the code requirement.

 

[boo1]

As JAE stated various loads may act on a structure or elements of a structure at the same time.
Because of this, the code specifies various combinations of loads (also known as load cases), that should be evaluated to determine which cases are critical to the structure. The '97 UBC combinations of loads are a significant change from previous editions with an emphasis given to strength design and a move toward ASCE 7 provisions. Load combinations for allowable stress design are specified in '97 UBC 1612.3.1. They are:

D (Eqn 12-7)
D + L + (Lr or S) (Eqn 12-8)
D + (W or E/1.4) (Eqn 12-9)
.9D ± E / 1.4 (Eqn 12-10)
D + .75 [L + (Lr or S) + (W or E/1.4)] (Eqn 12-11)

Where D = dead, L = live, Lr = roof live, S = snow, W = wind, and E = earthquake.

The live loads are assumed for design purpose. Concentrate loadings and distribution of the live load must be considered. The many varaibles are why an engineer should analysis the structure.