truss tie members eccentric
truss tie members eccentric
(OP)
I have got case where the tie members in the truss eccentric from where they should connect to the top and bottom chord so moment will appear on the top and bottom chord because of this eccentricity but how to calculate the moment diagram according to this eccentricity according to static






RE: truss tie members eccentric
If web members of a truss do not intersect the neutral axis of the top or bottom chord at a point, the truss can be analyzed as a rigid frame. Unless the eccentricity is substantial, this is usually not done, however.
BA
RE: truss tie members eccentric
thanks
RE: truss tie members eccentric
Personally, with such a small eccentricity, I would be inclined to ignore it.
BA
RE: truss tie members eccentric
thanks
RE: truss tie members eccentric
The more important issue is how you connect the flat bar diagonal tension members. A gusset through the SHS members would be one solution. Using another SHS for these webs might be a better detail.
RE: truss tie members eccentric
RE: truss tie members eccentric
thanks
RE: truss tie members eccentric
RE: truss tie members eccentric
Sketch the centrelines of the chords and the diagonals.
Measure the vertical distance between where the chords intersect and the centreline of the chord.
Now multiply the horizontal components of both diagonals by this eccentricty to get the total eccentric moment.
If your diagonals are evenly spaced then half of this will be distributed each way and you will get a sawtooth type configuration for your moment diagram.
As the chords are much less stiff then I usually ignore the distribution into these.
It is worth noting that the maximum moment from this eccentricity does not coincide with the maximum compression in the chord.
RE: truss tie members eccentric
So, I would suggest you use HSS 75x75 for all web members, both vertical and diagonal.
BA