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RE: Question on wood Roof Trusses

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Peter:

I personally have it in my specs that bracing the truss members is the
responsibility of the truss designer for reasons too numerous to
recount.this thread was started a while back so check the archives and in
particular excellent postings by Roger Turk .

I think the bigger problem is getting the framer to actually brace
the members that need bracing. and unless somebody shows him where these
members are on the framing plan
they aint gona walk the building with the little 81/2 x 11's from the
truss engineer and do it( all they see is a little astrisk next to said
members)
incidently every framer that we worked with told me that they have never
installed such braces and never knew they were even required .Generally
engineers have some sort of a typical detail on their plans that refers
back to the truss designer's calcs. good luck getting the framer to
comprehend it.
it is my opinion that unless the compression bracing is shown on the
truss layout sheet with the appropriate details refernced to it nobody
will follow
my 2 cents
Tarek Mokhatr
strucural engineer


>Peter McCormack wrote:
>
>>>Sorry if this is a repeat message, but I have been very busy the
>last couple of days and only gave my emails a cursive glance....to
>my dismay....
>
>Dennis...can you summarize the thread for me? Where do we
>stand (the building designer) are we responsible for the bracing,
>connections etc of the truss system, or is this the responsibility of
>the truss designer (who I had been assuming was responsible)
>
>The little truss diagrams I have seen specify the reactions at the
>heal of the truss, the assumed loading, but little information on
>laterial loading. For example, if I am responsible for the lateral
>bracing, how do I effectively design a bracing system without
>knowing if the "cladding and component" pressures I apply to the
>webs of a gable truss is the same as the truss designer to
>determine if I need to strengthen the webs with 'L' bracing or if the
>vertical diagonal bracing up to the top chord of an internal truss
>(and another to the bottom) will be adequate.
>
>As for the location and connections of bracing to prevent the out of
>plane buckling of the truss chords etc....do I need to analyze the
>system myself? What about the load-slip parameters of the metal
>plate connections?
>
>This is scary.....<<
>