pratt truss - angles or W beams
pratt truss - angles or W beams
(OP)
on my way home i noticed many pratt truss along the freeway supporting signs/directions. all members are angles.
i have also seen a calculation for a tower like structure, all angles including columns. all members were considered truss (including the columns) in Staad input.
but i have also seen a calculation of a pratt truss with top and bottom beams as W beams.
W beams were not considered as truss.
can someone explain the difference between these approach.
thanks,
i have also seen a calculation for a tower like structure, all angles including columns. all members were considered truss (including the columns) in Staad input.
but i have also seen a calculation of a pratt truss with top and bottom beams as W beams.
W beams were not considered as truss.
can someone explain the difference between these approach.
thanks,






RE: pratt truss - angles or W beams
Members of a truss can be any shape capable of carrying the load. Availability of material, architectural preference, ease of connection or a flip of the coin may be the deciding factor. It is not rocket science.
BA
RE: pratt truss - angles or W beams
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: pratt truss - angles or W beams
RE: pratt truss - angles or W beams
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: pratt truss - angles or W beams
I can't believe that you capitalized Staad and did not extend the same courtesy to Pratt.
Michael,
Continuous chords don't work well in my Maxwell diagrams.
RE: pratt truss - angles or W beams
When I was young and still figuring things out, I calculated the deflection as a truss, applied it to the continuous chords, and proportioned out the loads to each. It was a big effort because I wasn't quite sure where I was going with it, and it was not really worth it because the continuity contributed very little to the total.
Michael.
Timing has a lot to do with the outcome of a rain dance.
RE: pratt truss - angles or W beams
Mike McCann
MMC Engineering
Motto: KISS
Motivation: Don't ask
RE: pratt truss - angles or W beams
See Larry Muir's page on this one.
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