Components & Cladding
Components & Cladding
(OP)
I've got an industrial steel building end-wall where cladding dumps the wind loads onto girts, which then dump the loads onto wind columns (pinned at both ends). These columns are about 130' high, and are spaced at about 25'-30' o.c. The tributary area to these columns ranges from about 3,250 s.f. to 3,900 s.f. The reaction from the top end of the column goes into the roof bracing system, which dumps it into vertical braced frames. Are the wind columns components and cladding? Or are they part of the MWFRS?






RE: Components & Cladding
RE: Components & Cladding
RE: Components & Cladding
RE: Components & Cladding
RE: Components & Cladding
Big ole Crane building?
RE: Components & Cladding
I would be hesitant to build something that big (and housing the likely very expensive materials and equipment within) at minimum code. Buyers seldom understand the options to build stringer than minimum, nor do they understand that the code is intended only to protect life safety, not ensure ongoing usefulness if a maximum code-level event happens.
RE: Components & Cladding
RE: Components & Cladding
I've seen approaches like this thrown around, but have never seen where they come from. Is this in a code or textbook somewhere that you could point to as a reference? Reason I ask is we'll often be looking at one way concrete roof slabs or topping slabs for components and cladding and it seems overkill to consider the effective area of the whole thing. Would make more sense to do it based on span as you say, but I haven't been able to get a reference for that to justify it.
RE: Components & Cladding
The process that SteelPE referred to is found in ASCE 7-05 in the Definations section 6.2 of Chapter 6 Wind Loads under "Effective Wind Area, A". In ASCE 7-10 it is found in Chapter 26, Section 26.2 Definations.
RE: Components & Cladding
RE: Components & Cladding
You might have a roof truss that has a long span and a narrow spacing.
Example
Roof truss span = 50 feet.
Truss spacing = 8 feet.
Effective area = 50 x 50 /3 = 833 s.f.
Tributary area = 50 x 8 = 400 s.f.
The effective area is used ONLY to determine GCp values from the charts (which go to 1000 s.f.)
The tributary area is less than 700 s.f. limit so you would use C&C wind provisions vs. MWFRS provisions.