Punching problem

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PedReb
Posts: 3
Joined: Sun Mar 20, 2011 5:56 am
Location: FCT-UNL

Punching problem

Post by PedReb »

Hi guys,

I'm trying to do a punching analysis in a slab. I have to increase the load until a beam crush.
The problem is that I need the reaction in a node to compare to the maximum resistance so I create a recorder to save the information (the reaction in that node) every time the load increases. But can I read the file before all the load is applied?

And this code have an error?:

set R [open "Reaction.txt" r]

set file_data [read $R]

close R

the problem is that the Opensees gives me this error:

wrong # args: should be "set varName ?newValue?"

What am I doing wrong?

Thanks for helping!
evxjr
Posts: 20
Joined: Mon Nov 01, 2010 4:13 am
Location: University of Nottingham

Re: Punching problem

Post by evxjr »

If I understand your problem and you want to run the analysis until a certain nodal reaction then you can use a script similar to this:

set reaction 0
set reactionLimit 100
while {$reaction <= $reactionLimit} {
analyze 1
set reaction [nodeResponse $nodeTag $dof 6]; # The 6 is the ID for nodal reaction
}

This looks at the nodal reaction at each analysis step and continues until it hits the preset limit. This example is for static analysis but can be easily extended.
Beware the issue of never reaching the limit, you might what to include an extra check to ensure it will end at some point.

In regard to your code I don't know why you getting that error, from what I can see it looks fine and works for me, maybe you didn't place the [ ] correctly when you ran it or others may be able to offer more help. However in the last line it should be 'close $R' as you referring to the variable.
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