Learning Forum

[MickMack]

Hi,

I have been trying to broaden my understanding of the different ways to model concrete using Ansys Mechanical by reading a host of articles, discussions etc. I have tried to summarise this information as best i can and would appreciate some feedback, it is at the end of the post.

Can a coupled damaged plasticity micro plane model be carried out in mechanical using a static or transient model? Or does this need to be done in an explicit analysis?

I wanted to compare the results of a coupled damaged plasticity micro plane model to a Menetrey-William model with softening. To do this i created a model of Tech Demo 54, using a Menetrey-William material model, the properties that were not available in Demo 54 i took from TechDemo 49.

I have inserted the F-D curves from the Ansys Tech Demo Microplane model (blue) and the Menetrey-William model (grey) below. It appears to show a reasonable difference, the initial strenght at 8.5mm displacement is 62kN and 52kN respectively for the two models. After that the hardening cannot be replicated in the MW model.

I would welcome any further comments on these results to help my understanding of the difference between the two models.

[MickMack]

Hi Folks
I would appreciate any help, feedback or comments regarding this post,if you get a chance.

Cheers Michael

[MickMack]

Can anyone help me with this please?

[MickMack]

Would you be able to offer me any feedback/assistance with the post above.

Thanks Michael

[ErKo]

As I said in previous post if we get within 10 - 20 % of the failure load (~62 kN) ,which you have (~55 kN / MW as I can see from the first plot) for the MW model, that is what we can expect, and quite OK I would say - post failure these material models are very different so they would not agree, and in design one would perhaps not like to be there so one would go for the failure load and forget about the post failure response which is not something MW would do excellently since it is a plasticity model without cracking and damage (so use it upto failure), so that is all I can say - can not really comment more since I do not write the material models and do not know their details.

All the best

Erik

[MickMack]

Thanks for the response.

[ErKo]

NO worries - I am glad to see that you got pretty close to the failure load with MW - perhaps if one really wanted, one can do a study, say varying the fracture energy and some other mat. parameters to see how that affects the post failure response.

Erik

[MickMack]

Hi guys
Can anyone offer any further advice/comments on the first post, particular the difference between the models

Can a microplane be used in mechanical, if so how is it included?

Anyone any idea on the f-d data used to validate showcase 54.

Thanks Michael

[MickMack]

Hi folks
Any assistance would be great.

Thanks
Michael