Problem with node recorder

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xantis85
Posts: 18
Joined: Tue Sep 06, 2011 7:54 am
Location: FedericoII

Problem with node recorder

Post by xantis85 » Mon Mar 14, 2022 5:44 am

Hello,
I'm having some trouble with the node recorder command when recording accelerations. If I use the UniformExcitation pattern, the outputs will be relative displacements and accelerations. However, according to the guide for nodeRecorder command, if I use:
recorder Node -file nodesA.out -timeSeries 1 -time -node 1 2 3 4 -dof 1 accel;

"For a UniformExcitation analysis, this command generates output file nodesA.out that contains absolute accelerations (ground motion acceleration + relative acceleration) in x direction for nodes 1, 2, 3, and 4. NOTE that if no TimeSeries is provided and a uniform excitation analysis is performed, the relative accelerations are recorded."

If I use the following commands:

timeSeries Path 4500 -dt 0.005 -filePath $path1
pattern UniformExcitation 4501 1 -accel 4500 -fact 9.806

recorder Node -file "Data/ACC.out" -timeSeries 4500 -time -nodeRange 1 6 -dof 1 accel;
recorder Node -file "Data/DISP.out" -timeSeries 4500 -time -nodeRange 1 6 -dof 1 disp;


for node 1 (the only one constrained), I obtain exactly the same values for accelerations and displacements. It seems that the nodeRecorder always record displacement for contrained node.

Further, I have another problem, since if instead of using:
timeSeries Path 4500 -dt 0.005 -filePath $path1
pattern UniformExcitation 4501 1 -accel 4500 -fact 9.806

I use :
timeSeries Path 4500 -dt 0.005 -filePath $path1 -factor 9.806
pattern UniformExcitation 4501 1 -accel 4500 -fact 1.00
using "-factor 9.806" in the time series, the results are completely different.

Thank you in advance for any help
xantis85

mhscott
Posts: 875
Joined: Tue Jul 06, 2004 3:38 pm
Location: Corvallis, Oregon USA
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Re: Problem with node recorder

Post by mhscott » Mon Mar 14, 2022 6:35 am

Please provide a minimal working example that replicates the issue.

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