numerical errors in pre-damage speciment

[giom]

Hello everyone!

I modelled a speciment of infill masonry wall in STKO. For the materials I use ASDConcrete3D and DamageTC3D, using IMPL-EX for integration type. On this speciment I want to apply two types of analysis:

1. An out of plane analysis only (without pre-damage the speciment)
2. An in-plane cyclic analysis and then an out of plane analysis (which means pre-damage the speciment)

In the first case I haven't any problem, the analysis goes on very well.
On the contrary, in the second case I have a lot of numerical errors. Specifically, these errors occur in the out-of-plane analysis after application of a in-plane cyclic analysis (as you can see in attached monitor screenshot).

Why do I have these instabilities? Is there anything in the model to change? Is there a way to eliminate them?

.sdc file in attached files

Thank you very much for the answer!

Giovanni

[STKO Team]

1. make sure you have the latest version of STKO and OpenSees-Solvers (probably you still have the initial beta version of the ASDConcrete3D). I don't have such huge instabilities.
2. After the first displacement control, reset the pseudo-time to zero. It is not super important in your case because (due to the magnitude of the reference load) it is small, but typically you should reset it to 0, because the following analysis

This is a modified file (check the mesh size):

URM_7-BC-UR_incastro_completa.zip

(979.99 KiB) Downloaded 154 times