drift response

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jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

drift response

Post by jackmil »

dear all
how can i control drift by using the eleResponse Command?! its unclear for me.
how can i use the command for this drift recorder :


recorder Drift -file "$dataDir/$subDir1/Drift.out" -iNode 141 -jNode 111 -dof 1 -perpDirn 2;

set DriftStep [eleResponse ? ? ? ? ? ]
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: drift response

Post by vesna »

what exactly do you want to do?
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

Re: drift response

Post by jackmil »

i wanna get the drift in each step of cyclic or dynamic analysis and check it in a loop,but i dont know how ,i mean i don know how to write the eleResponse command;

[eleResponse ................?................]

recorder Drift -file "$dataDir/Drift.out" -iNode 141 -jNode 111 -dof 1 -perpDirn 2;
if i wanna get the stressStrain of outer fiber of for example hss-fiber section, i dont know how i fill the blank following example below:

eval recorder Element -file "$dataDir/StressStrain.out" -ele 14006 15006 section 3 fiber ...?... stressStrain;
i cant understand the modeling SCBF opensees discovering,
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: drift response

Post by vesna »

you can use nodeDisp command (http://opensees.berkeley.edu/wiki/index ... sp_Command) to calculate the drift.

to retrieve stress of a particular fiber during the analysis here is an example:

set stressFiber1 [eleResponse $matTag section 3 fiber $fiberNumber stress]

following $matTag arguments are the same as the ones you would use within recorder
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

Re: drift response

Post by jackmil »

thank u very much !!
really appreciate ur concern dear vesna !
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

remove some elements

Post by jackmil »

dear vesna
hello
thank u for ur attention;
can i use the remove command like this for ElementS?

set eleList "10006 11006 12006 13006"
evel remove element $eleList ?
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

Re: drift response

Post by jackmil »

for removing a brace that built ten segments,do i have to remove all of the segments to cansel of barce action? or there is another way to do this easier? wasnt there any problem for example deleting elements for convergence problem?
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: drift response

Post by vesna »

I think that with the "remove element" command you can remove only one element. to remove all segments of the brace you will have to issue several remove element commands. if you do it within a loop it may not be that difficult.
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

Re: drift response

Post by jackmil »

ofcourse... omm but should i remove the rotational springs in the first and end of the brace too in addition to removing the segments and dangling nodes of the brace?? how about the ghost trusses to the braces ( to diminish convergence problems )
vesna
Posts: 3033
Joined: Tue May 23, 2006 11:23 am
Location: UC Berkeley

Re: drift response

Post by vesna »

I would remove all of it.
jackmil
Posts: 32
Joined: Wed Jul 31, 2013 1:09 pm

Re: drift response

Post by jackmil »

dear frank
dear vesna
i really need your help . . .
i would remove all the bracing segments and their dunglin nodes, but during the analysis, when model reached its limitation by using eleResponse limit state and removed their element and related nodes , it faced with some errors. i think that i should apply some other commands that i dont know them.
does the Opensees understand when the bracing segments removed,stiffnes matrix of model must be changed or updated?
do i remove the recorder with respect to the bracing segments too?
fmk
Site Admin
Posts: 5884
Joined: Fri Jun 11, 2004 2:33 pm
Location: UC Berkeley
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Re: drift response

Post by fmk »

OpenSees takes care of the stifness; yes remove the recorders.
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