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I know that put command add to the computing time so I bet the answer to your question is yes it does.
To prevent the test from displaying success, you can change the flag to 0:
test EnergyIncr $tol $iter <$pFlag> <$nType>

Got it.
Thanks for the explanations and the help!

Thanks for the help. I do use Penalty for constraints.
I did check as you suggested between the acceleration given by Newmark for the displacement time series and between the accelerations values I get from the OS models. They are 100% equal.

I do not understand however your suggestion as to impose the acceleration. From what I understand, if I specify a -acc in the ts of the gm, it will be integrated to disp?
I did try to do it using the original acceleration time history in a ts along with the displacement but that didn't change the outcome. I tryed several others thing that all failed (using interpolated gm). Is there a trick to impose the acceleration? Here's my line for the imposed motion.
pattern MultipleSupport 7 {
groundMotion 1 Plain -disp $mSeries -accel $nSeries
#groundMotion 2 Plain -accel $nSeries
#groundMotion 0 Interpolated 1 2 -fact 1. 1.
for {set i 1} {$i<=[expr int($nbrx3)]} {incr i 1} {
imposedMotion [lindex $table_node_bottom [expr int($i-1)] 0] 1 1
}
}
Thanks for help.

Exact, thought the displacements are the same.

Thanks!

From what I know, you can use 'parameter' and 'updateParameter' OpenSees commands. See the docs for the syntax. You can use this approach when the materials of interests have setParameter method in cpp source files.

You can see for Viscous mat here : //github.com/lge88/OpenSees/blob/master/SRC/material/uniaxial/ViscousMaterial.cpp
However, I did not see the setParameter in the file so I think you cannot do it with this material.

For your problem, hopefully I didn't get you all wrong, but maybe try something simple like
incr Damper_counter1 1
incr Damper_counter2 1
at each steps?
That is your material command : uniaxialMaterial Viscous $Damper_counter1 $c1 0.0;
So the Id of the material is Damper_counter1 and the value is c1. The value you should increase in each steps is Damper_counter1 not index_damper1?
Hope it helped, GL

Hi,
Is there a way to define region without manually entering each entry ? Like in a for loop?
Say I have 100k element, not in numerical order (sometime a number is skipped because I removed a element during analysis), stored in a list and I want to include a recorder. I don't want to write down each entry like : region -ele 0 1 3 50 5....that's awfully long.
I tryed something like region [for {loop over list}] but it didn't work out. Any idea? Thanks!

Thanks for your answer.
Maybe I should've mention that I use the multi-support excitation pattern to apply my displacement. If I am right it uses the ABSOLUTE values, and not relative values as in the case of a UniformExciatation?
That's how I apply the EQ :
set mSeries "Path -dt 0.002 -filePath $file_Id -factor $C_Facteur"
pattern MultipleSupport 19 {
groundMotion 1 Plain -disp $mSeries
for {set i 1} {$i<=[expr int($nbrx3)]} {incr i 1} {
imposedMotion [lindex $table_bottom [expr int($i-1)] 0] 1 1
}
}
With $C_Facteur ==1

Hi,
I am conducting dynamic analysis of a soil deposit. I apply the dynamic signal using displacement time history at the bottom of the soil deposit. The disp history comes from synthetic acceleration time history of scaled earthquake. I went from acc to disp using Range kutta 4th.
I record the acceleration at every node in the soil domain. Then I can check any points. When I checked the node where the displacement time history is applied and I traced the Response spectrum, I was surprise to see that it greatly differs from the RS I obtain from the original acceleration time history (the one I used to determine the displacement that is applied to the model). However, when I trace the displacement and I compare it with the imposed displacement, both are the same.
So I wonder why the acceleration I record in my model differs from the acceleration time history that I used to obtain the displacement imposed whilst the displacement are the same?
In RS from the original acceleration time history, I get around 9m/sec² as maximum whilst in the recorded I go over 12?

Thanks

Hi,
If I reduce the number of recorder in a model will it speed up the analysis process or will it changes nothing?
Thanks!
I would also be very happy to hear about possible options (if any) to reduce processing time for large model.

That would depend on the recorder used and on the material output.
For example, for the PIMY material (http://opensees.berkeley.edu/wiki/index ... d_Material)
it would be, as specified on the material's page : For 2D problems, the stress output follows this order: σxx, σyy, σzz, σxy, ηr, where ηr is the ratio between the shear (deviatoric) stress and peak shear strength at the current confinement (0<=ηr<=1.0). The strain output follows this order: εxx, εyy, γxy.
Remember that if in the recorder command -time was entered, the first column will be the time of the system.

You can display the element response on screen to see what the recorder will return in the output file using command EleResponse (http://opensees.berkeley.edu/wiki/index ... se_Command)
Check this file for more specific details and example : http://opensees.berkeley.edu/wiki/image ... Output.pdf
Hope it helps, GL

I would check three thing.
1-ensure you have good fix condition and draw the frame to make sure node coord. and element are placed where you intended them to be (you can use a post-treat like GiD to show the model).
2-Check for the mass (make sure they aren't too large?)
3-Check the definition of your materials (did you provide consistant units?) and check your fiber section (check if you defined them well. Here is an example for fiber construction : https://searchcode.com/codesearch/view/43081462/). Also check the rigid joint connection (usually use a elastic element with high stiffness to connect beam and column to ensure the rigidity of this connection... how are these elements defined in your model? If it's too weak, the whole model will be weak and hence have long periods).
Just think about w=sqrt(K/M). Easy to check if M is correct, but alot of thing can affect K.
What constraint handler do you use btw? Transformation?
Right now, your model either have too high mass or too small K (in proportion to each other).

GL

The solution to the eigen problem involes the M and K matrix. In my understading (which might be wrong of course) unless your load bring a modification to the rigidity matrix (yielding) there is no reason that application of a load change the outcome of the analysis.

No, i don't think it is if you have a simple model.
Did you check example on the OS wiki? They are very well prepared.
http://opensees.berkeley.edu/wiki/index ... _Analysis)