fiber recorder and zerolenght elements

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acv
Posts: 6
Joined: Wed Mar 05, 2014 9:32 am
Location: NTUA

fiber recorder and zerolenght elements

Post by acv »

I am trying to perform a moment curvature analysis and also record the stress and strain of certain fibers of the rc section. this example(http://opensees.berkeley.edu/wiki/index ... re_Example) is very helpfull but an zeroLengthSection element is used so
the following command cannot be used :"recorder Element -file Element1.out -time -ele 1 3 section 1 fiber 0.10 0.10 stressStrain ".
The valid queries to a zero-length element when creating an ElementRecorder object are 'force,' 'deformation,' 'stiff,' and 'section $secArg1 secArg2 ...'.
I tried to build another model using a forceBeamColumn element and two nodes
node 1 0.0 0.0 node 2 0.0 0.1
I also increased the max number of iterations .(test NormDispIncr...100...)
Although this model works the recorders return far less steps than moment/curvature analysis and i'm not sure that my model gives equivalent results because the axial load is not applied on the section where the curvature is meassured.

Can anyone suggest another model for moment curvature analysis or a command that can be used to record fiber strain of zeroLengthSection elements??? i would appreciate any idea.
Wenwen
Posts: 5
Joined: Mon Sep 24, 2012 6:25 am
Location: Chongqing

Re: fiber recorder and zerolenght elements

Post by Wenwen »

Just remove the $secArg, then you can get the fiber strain. Try this:"recorder Element -file Element1.out -time -ele 1 section fiber 0.10 0.10 1 stressStrain ".
acv
Posts: 6
Joined: Wed Mar 05, 2014 9:32 am
Location: NTUA

Re: fiber recorder and zerolenght elements

Post by acv »

It works :D :D :D :D :D :D :D :D :D :D
thank you very much
:D :D :D :D :D :D :D :D :D :D
yangyankai
Posts: 3
Joined: Wed Jun 11, 2014 7:27 pm

Re: fiber recorder and zerolenght elements

Post by yangyankai »

Wenwen wrote:
> Just remove the $secArg, then you can get the fiber strain. Try
> this:"recorder Element -file Element1.out -time -ele 1 section fiber
> 0.10 0.10 1 stressStrain ".

I want to know about this Strain, becauce I think the strain is curvature, if I want to know the fiber's stress-strain, how to get it?
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