How can i add shear deformation?

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pimkkk
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How can i add shear deformation?

Post by pimkkk »

Hi there

could you please let me know how i can add shear deformation on a column, like what element should i use, nonlinear or dispBeamColumnInt?
what material should i use, only steel or steel and concrete?

Thanks a lot!
fmk
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Post by fmk »

you can use the forcebeamColumn with a aggregated section consisting of a fiber section and a material that provides the shear-deformation or you can use the dispBeamColumnInt .. it's up to you.
pimkkk
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Post by pimkkk »

thanks a lot, by forcebeamColumn do you mean nonlinear element?
fmk
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Post by fmk »

they are the same .. however, i am pushing the use of the term forceBeamColumn as it is not the only nonlinear Beam Column element.
pimkkk
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Post by pimkkk »

so whats the difference between forcebeamColumn and dispBeamColumnInt??

and i have one more question, how can i get the result of the displacement of each intgrate point within one element?

thanks~
jwgolf
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Post by jwgolf »

I believe the difference refers to the way the analysis increments from the current configuration towards the next converged point of a force-displacement relationship. Meaning the force-based element uses an increment in force and the displacement-based uses an increment in displacement.

You can obtain quite a bit of useful information from any of your Gauss-Lobatto integration points (including displacements). This is done using the Element recorder, where you can specify exactly what integration points to capture and what data you're interested in.
pimkkk
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Post by pimkkk »

so is this mean i need to have 100 recorder commands if i wanna record 100 indegration points within one element? But i didnt find the command for indegration point at element recorder command, could you please give me an example?

thanks~
jwgolf
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Post by jwgolf »

Here is an example...


recorder Element -file Output.dat -ele 547 557 569 section 5 deformation


Your best bet is to export all of the integration points in one recorder object and pick out the points of interest with a program like Matlab. Simply replace "section 5" with "section all" and you can capture all of the integration points.

See the users manual page in the old manual for Element Recorder so you can change the "deformation" part of the command so you are capturing the data you're interested in. Right now it's capturing axial-strain and curvature for the section.
pimkkk
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Post by pimkkk »

i used this
recorder Element -file datahaha.out -ele 1 section all fiber 0.1 0.1 deformation;
to record my column, which is a one element, 10 integrated points column, but there is no result, and no error warning...

could you please let me know what the problem is? thanks~
fmk
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Post by fmk »

all is not an option yet .. you need to record sections one at a time.
pimkkk
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Post by pimkkk »

sorry fmk. what do you mean by record sections one at one time? i cannt find section record command in the manual, please give me an example, thanks
fmk
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Post by fmk »

this does not work:

recorder ... section all ...

this does:

recorder ... section 1 ...
recorder ... section 2 ..
recorder ... section 3 ...
pimkkk
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Post by pimkkk »

# element connectivity:
set numIntgrPts 10; # number of integration points for force-based element
element nonlinearBeamColumn 1 1 2 $numIntgrPts $ColSecTag $ColTransfTag ; # self-explanatory when using variables

puts "4";

#record----------------------------------------------------------------
for {set j 1} {$j < 11} {set j [expr {$j+1}]} {;

recorder Element -file datahaha/DFree$j.out -ele 1 section $j deformation;

};

i use this to do record, now i can get results, but all the results are the same, please tell me what the peoblem is, many thanks~~
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