CustomCommand

[gercekonur]

Dear STKO Team,

I have added the TCL file of cyclic loading from your tutorials as a custom command. However, I received the error attached. I would like to ask you If you could help me.

Thank you in advance.

Best regards,

[STKO Team]

Dear user, adding the cyclic displacement-control with a custom script was an old way of doing it.
In the new STKO version (I think you are using version 1.1.5) the error happens because the Analysis command you put before the custom script has the wipeAnalysis option checked by default (it was not available in the previous version).

So you can either switch-off the wipeAnalysis option in the Analysis command that comes right before your custom script,
or you can use the new method for doing a cyclic displacement-control analysis:

In the analysis command, when you choose the displacement control, there is a Cyclic option. If you check it, you can specify a timeSeries for the target displacement (instead of a fixed value). In this way, it will automatically run a cyclic displacement control. Of course the timeSeries Y-values should have the unit of displacements.

Let me know if you manage to do it. Otherwise, you can send us your SCD file (attach it here as a zip) and we will convert it for you

[gercekonur]

Dear STKO Team,

Thank you so much for your prompt reply.

Indeed the problem was the wipeanalysis option which was checked. However, I switch-off it and it ran

I would like to ask you a question about the cyclic option in the analysis command.

I used the same parameters (the one from the script) for the cyclic option. However, it has a convergence problem. So that, while the model was running with the script (the old version), it didn't work properly with the cyclic option. Do I need to pay attention to other parts as well?

Best regards,

[STKO Team]

Dear user, we had a look at your file.
The way you applied the cyclic option in your displacement control was almost right: The only error was that your cyclic timeSeries was normalized to 1, while when you use it for cyclic displacement control, it should have the real displacement value (in your case 50 mm).

However the error is another, and it is more theoretical. Since your horizontal load is an imposed displacement, you should run a load-control analysis. The displacement-control is to be used when you apply a force, and you want to control its magnitude (load multiplier) not with a timeSeries, but with the displacement-control integration scheme.

So here is your fixed file. Now it uses an adaptive load control, since your applied load is an imposed displacement. I also added the new monitor feature, that allows you to monitor the force-displacement curve in real-time during the analsyis

_2_cyclic.zip

(169.32 KiB) Downloaded 169 times

[gercekonur]

Dear STKO Team,

Thank you so much.

I like the monitor a lot. It is very nice to see. Do we need to create selection sets in order to monitor the forces? (I have two different selection sets in my file)

[Clarabella]

Yes you need to create selection sets. For example a node for the displacement and the nodes at the base for the total base shear. You can monitor as many curves as you want and superimpose it to a graph which could be experimental data or a previous analysis.