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Truss end connections

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I am currently involved in checking heavy long span truss connections.
The trusses in question frame into column flanges.  The detailer's
engineer is using the Uniform Force Method to resolve the forces at this
connection.  His mathematical method is correct but my question is whether
the Uniform Force Method is a valid analytical method for this
application.  AISC Volume II Connections only uses Uniform force Method
analysis in regard to vertical bracing applications.  Does it matter how
the axial force originates?  For example: In the vertical brace case,
compression in the horizontal member is a result of that member being
compressed between 2 columns.  This compression strut in effect will bear
against the column.  Compression in the top chord of a truss on the other
hand is a result of internal stresses and will in effect result in the top
chord of the truss to shorten.  This  would seem to result in the
compression chord to want to pull away from the column.  I guess my
question is if the uniform force method is applicable to the truss end
condition, does the horizontal component at the gusset/column interface
have to be resolved somehow at the top chords connection at the column.
(Reference fig.7-50 page 7-108 AISC Volune II Connections-ASD 9th ed.)

I've always resolved the forces similar to the methods shown on page 7-60
of the above referenced manual.

Any information would be greatly appreciated.

Todd Hill, PE