Elastic Response Spectra Script

[silvia]

that's a dynamics question.

[ebe79442114]

I wrote a program with Matlab language, that correct the row acceleration data and draw the response spectra.I released it under Gnu general public licence.
It draws response spectra with three methods.
address:http://rapidshare.com/files/62694518/Se ... ar.gz.html

[mkumar07]

Hi there!

I have performed the elastic time history of 124 ground motions using this code; the results are seriously contrasting to Seismosignal (another software). I am very sure results of Seismosignal are right.

But, I cannot find any mistake whatsoever in this code (except for the damping) but cannot see anyother mistake.

Please help.

Kumar, M.

[silvia]

look for a systematic difference/error.

[mkumar07]

Dear Silvia,

I couldn't find a systematic error at all; the difference in both software is random. It is kind of strange that such a simple code which seems logically correct is causing this difference in results.

Thanx for your prompt response.

Kumar, M.

[foadEng]

Hi
The topic here is about elastic response spectra. I wanted to know about inelastic response spectra. Can we generate inelastic response spectra with this algorithm?
Than you very much!

[felipe_cordero]

if you have a too many ground motion files, the script fails because it opens every time the tmpEnvelop files.

It happens when we use;

set Dcontent [read [open tmpEnvNodalDisp.out ]];
set Di [lindex $Dcontent 2];
puts Sd$Di
set iDi "$iDi $Di";

I recommend to use the following lines:

set in [open tmpEnvNodalDisp.out];
set Dcontent [read $in];
set Di [lindex $Dcontent 2];
#puts Sd$Di
set iDi "$iDi $Di";
close $in;

This way closes the tmp file once it is used.

Thanks any way for the script, It has been very useful for me.

[naba077]

I'm sorry, but when I run the program, it says that
"can't read dt: no such variable"
What does that mean?
Where should I define dt and what is dt?

[naba077]

And also how to define these variables?
"
set iGroundFileSMSR {"IV79cal" "IV79chi" "IV79e01" "IV79e12" "IV79e13" "IV79qkp" "IV79wsm" "LV80kod" "LV80srm" "MH84agw" "MH84g02" "MH84g03" "MH84gmr" "PM73phn" "PS86psa" "WN87cas" "WN87cat" "WN87flo" "WN87w70" "WN87wat" }
#small magnitude, large distance
set iGroundFileSMLR {"BO42elc" "CO83c05" "CO83c08" "IV79cc4" "IV79cmp" "IV79dlt" "IV79nil" "IV79pls" "IV79vct" "LV80stp" "MH84cap" "MH84hch" "MH84sjb" "PS86h06" "PS86ino" "WN87bir" "WN87cts" "WN87har" "WN87sse" "WN87stc" }

#large magnitude, small distance
set iGroundFileLMSR {"IV40elc" "LD92yer" "LP89agw" "LP89cap" "LP89g03" "LP89g04" "LP89gmr" "LP89hch" "LP89hda" "LP89svl" "NR94cnp" "NR94far" "NR94fle" "NR94glp" "NR94hol" "NR94stc" "SF71pel" "SH87bra" "SH87icc" "SH87wsm" }
#large magnitude, large distance
set iGroundFileLMLR {"BM68elc" "LD92ind" "LD92psa" "LP89a2e" "LP89fms" "LP89hvr" "LP89sjw" "LP89slc" "NR94bad" "NR94cas" "NR94cen" "NR94jab" "NR94lh1" "NR94loa" "NR94lv2" "NR94php" "NR94pic" "NR94sor" "NR94sse" "NR94ver" }
set iGroundFileLMLR {"SH87wsm" "BM68elc" "LD92ind" "LD92psa" "LP89a2e" "LP89fms" "LP89hvr" "LP89sjw" "LP89slc" "NR94bad" "NR94cas" "NR94cen" "NR94jab" "NR94lh1" "NR94loa" "NR94lv2" "NR94php" "NR94pic" "NR94sor" "NR94sse" "NR94ver" }
"
When I assume dt and run the program it displays that
"Warning- Pathseries :: Pathseries ()- could not open file GMFiles/......g3"

Would you also please upload a example ground motion file so that I'll confirm that my ground motion file is OK.

[fawadnajam]

How can this script be modified to get inelastic spectrum? I want to model elastoplastic and flag-shaped behaviors and want to get peak displacements of SDOFs.

[seraphpan]

fawadnajam wrote:
> How can this script be modified to get inelastic spectrum? I want to model elastoplastic
> and flag-shaped behaviors and want to get peak displacements of SDOFs.

Hi Fawadnajam,

How's your work now? Have you successfully plot the inelastic spectra? I am trying to do similar stuff and kinda confused for a long time.

Thanks

Seraph

[vantanhy]

Dear Silvia
About the damps I found large difference according to K-prop factor and M-prop factor. Which one should I use?
When T>1s acceleration values uing M-prop factor are larger when uing the other softwares, also larger than the elastic response spectrum. How to deal with this problem?

Thank you!

[fmk]

there will be large differences if you are doing inelastic response spectra and you specify mass proportional or stiffness proportional (current stiffness) damping .. using mass proportional the C is constant, using stifness proportional the C is changing .. hence the damping forces are different .. most inelastic spectrum would be determined using a constant C matrix, i.e. mass proportional (or initial stiffness)