Abaqus 6.14 CAE - Imperfection Study

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Ben_P_1992
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The title of the project is as follows:
A study of the effect of imperfections on the buckling capability of a soda can under axial loading.

My group and I are aiming to carry out the following:
  • Linear buckling analysis of soda can to gain first 5 eigenvalues
  • Riks buckling analysis with plasticity and the introduction of imperfections in the form of wall thickness
  • Riks buckling analysis with plasticity and the introduction of imperfections in the form of out-of-roundness
  • Experimental analysis on an Instron machine to compare with results gained on Abaqus CAE
The following steps were carried out for he linear buckling analysis:
  • Create part (Shell, extrusion)
  • Apply material properties and section
  • Mesh – Sweep
  • Sets of up and down slave nodes with master reference points
  • Steps – Linear perturbation, Buckle
  • Apply constraints, BCs and load
The same was then carried out for the Riks analysis with the following changes:
  • Add plasticity values for material using true-stress strain curve
  • Steps- Riks, static step
  • Load is set for that to be equal to first buckling load (-2554.5 Pa)
  • Apply load equal to that of the first buckling load
  • Introduce imperfections using edit keywords window
    • Max deformation from linear buckling analysis normalised (1/1.092E-03)
    • Multiply by thickness (0.097E-03)
    • Multiply by 0.1 for 10% imperfection, 0.2 for 20% and so on
  • Using edit keywords window, type in what's shown on the attached image (where Buckle_load are the results from the linear analysis)
We are now a little stuck on how to compute the imperfection in terms of out of roundness. Any suggestions would be much appreciated!
 

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Hi Ben_P_1992!

I'm new user of ABAQUS. I hope you can help me to train some knowledgement about ABAQUS related to imperfection+ static ,Riks method with educational fee

Hope receive your reply?Sincerely!My email: thanhhabk2006@gmail.com ur email?Ben_P_1992
 
Hi
i am trying to model a cyclic load for a pipe-elbow and when i run the model it shows me the following error: :Time increment required is less than the minimum specified". Could anyone please give me some suggestions on how to eliminate this error. I have tried to change the time step, the time increment and the seeding of the model but didn't help.
Thanks in advance