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RE: STAAD Results interpretation

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Thanks for the advice. That's what I'm doing when I received your mail. I
just need experts' opinions on this. Also, I am browsing through the
computations of my previous office and comparing the results of ETABS and

We can't just trust a computer program even though it is used by 50,000
engineers worldwide. After all they have a disclaimer for it. When a
structure fails, we can't say "there is an error in the program". 

	Any other opinions?

A. Yango
> ----------
> From: 	Christopher Wright[SMTP:chrisw(--nospam--at)]
> Reply To: 	seaint(--nospam--at)
> Sent: 	Tuesday, May 18, 1999 9:11 PM
> To: 	seaint(--nospam--at)
> Subject: 	RE: STAAD Results interpretation
> >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)        | this distance"   (last words of Gen.
> ___________________________| John Sedgwick, Spotsylvania 1864)