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Re: Seismic Lateral Load

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>Do I have to apply
>the Fx (determined node load)to all joints at the same level or divide
>the Fx by the number of joints on that same level.
This is a good rule for any finite element software when you're not 
absolutely certain how it will apply loads--
Make a simple model with loads applied the way you suppose they should 
go. Check the reaction forces and moments (all six equilibrium equations) 
against what you think the input loads should be. If the reactions 
equilibrate the applied loads within 5 significant figures, you got it 
right. Checking within three significant figures is usually ok, but might 
want further checking (like the effect of arcs modelled as chords) to 
make sure it's not an input error. Less than three figures means bad 
software or input problems.

I've found hundreds of my own (and other people's) mistakes, program bugs 
and documentation errors this way. And, 30 years after my last mechanics 
class, boy, can I draw free-body diagrams. ;-> 

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