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RE: STAAD Results interpretation

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>I'm trying to figure out the Fx, Fy, Fxy and angle ( for Print Element
>Forces) and is still in the process of doing so up to now. I hope you could
>help me out on this.
Although I'm certain the force convention is covered in the docs, this is 
something you should dope out for yourself--it's the only way to verify 
FEA results. 

Run a simple problem with a known obvious answer like an end loaded 
cantilever beam. Print out all the results. The Fx, Fy and Fxy numbers 
should be immediately recognizable from what you know about the force 
distribution in a cantilever. Just to be sure you put in the properties 
correctly, check the end deflection from elementary theory. If the 
effects of orientation aren't obvious, model the beam at a 45 degree 
angle with the coordinate axes. Try it again with gravity loading so you 
can see where that enters in. After you've figured it out for the 
cantilever go back into your real problem and verify your conclusions by 
checking equlibrium with a couple of elements. Draw a free body diagram 
and apply the loads as you found them from your demo problem. Calculate 
the resultant forces and moments and verify that the equations of statics 
are satisfied. If you can't get no satisfaction, either you have the 
blues or you've made a mistake applying the loads, guessed wrong for the 
sign convention or there's a program bug at work (with the likelihood 
pretty much in that order). If you can't do this equiibrium check, work 
at it until you can; otherwise you'll forever be at the mercy of every 
bug or documentation error the program has to offer.

Christopher Wright P.E.    |"They couldn't hit an elephant from
chrisw(--nospam--at)skypoint.com        | this distance"   (last words of Gen.
___________________________| John Sedgwick, Spotsylvania 1864)
http://www.skypoint.com/~chrisw