dynamic analysis

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alessandro.paparo
Posts: 22
Joined: Sat Feb 07, 2009 1:43 am
Location: bologna

dynamic analysis

Post by alessandro.paparo »

Hi all!
When i run a dynamic analysis for a MDOF system, i must use a different mode of programming from the programmation for a SDOF?

For example, for a SDOF for uniform acceleration input at all support nodes, I have to put:

"
set GMdirection 1;
set GMfile "R2.acc" ;
set GMfact 1.0.
"

I ask that because in the example files for a portal (and for all the structures except the cantiliver) there are a different way of programming:

"
set GMdirection 1;
set GMfile "H-e12140" ;
set GMfact 1.5;

source ReadSMDFile.tcl;
set inFile $GMdir/$GMfile.at2
set outFile $GMdir/$GMfile.g3;
ReadSMDFile $inFile $outFile dt.
"

What means the last 4 lines?
they are foundamental?
If i do an analysis without them there a difference from the output files?

Thx!!!
silvia
Posts: 3909
Joined: Tue Jan 11, 2005 7:44 am
Location: Degenkolb Engineers
Contact:

Post by silvia »

the input motion files are different.
in the first case you have an acceleration-only input file. no changes are needed for it.
in the second case you have file from the PEER database which has a header to it. the readsmd file removes the header and reads what dt is. have a look at the groundmotion files and at the scripts.
Silvia Mazzoni, PhD
Structural Consultant
Degenkolb Engineers
235 Montgomery Street, Suite 500
San Francisco, CA. 94104
alessandro.paparo
Posts: 22
Joined: Sat Feb 07, 2009 1:43 am
Location: bologna

Post by alessandro.paparo »

ok.
thanks!
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