Plasticity in fenics

#1

Dear all,

I am trying to implement plasticity in FEniCS. I find an extremely valuable tutorial here (Courtesy @bleyerj ). Thanks a ton @bleyerj . I tried to match the result of the FEniCS code with the Abaqus so that I can build upon that. But unfortunately, the displacement at the end of the simulation from FEniCS and Abaqus are not matching.

. As you can see, at the end displacement are very different. Though, the onset of plasticity is approximately at the same displacement. Am I missing something in Abaqus? For the reference, I have attached the input file of Abaqus here (for the suggestions from any of folks here who are familiar with Abaqus as well might help).

Also, are there anymore sources of plasticity in FEniCS so that I can explore further? Any pointers in that direction will be useful.

OS: Ubuntu 16.04LTS
FEniCS version: 2017.2.0

Thanks in advance,
Peter

#2

Hi,
thanks for the comment on the plasticity example. I haven’t compared to Abaqus but I get identical results between the FeniCS implementation and another completely independent implementation of FE plasticity.

I am not an experienced Abaqus user but your time goes up to 1., what is your imposed loading ? it seems from your input file that your final load is 75.751 right ? What does it correspond to? In the example, I go up to q_{lim}*\sqrt{1.1} which is around 79.4347

#3

Hi @bleyerj,

Thanks for your reply. My bad. I did not notice that q_{lim} * \sqrt{1.1}. Now, it matches with the answer provided by you. Extremely sorry for the mess up.