1 (edited by yzhang 31-10-2017 00:07:02)

Topic: Question about PiecewiseLinFunction: No success in solving problem

Hi,

I'm using PiecewiseLinFunction to define my loading.
When I use " PiecewiseLinFunction 1  t 3 0. 5 10 f(t) 3  0. -1 -0.001 ", it works well.
But when I change it to " PiecewiseLinFunction 1  t 3 0. 5 10 f(t) 3  0. -1 0.001 ", it can not calculate.

Error: (/Users/Yige/Downloads/oofem/src/sm/EngineeringModels/staticstructural.C:393)
In StaticStructural::solveYourselfAt:
No success in solving problem
_______________________________________________________
stack trace:
  2   liboofem.dylib                      0x000000010af6e0d9 _ZN5oofem16StaticStructural15solveYourselfAtEPNS_8TimeStepE + 6249
  3   liboofem.dylib                      0x000000010aadddae _ZN5oofem10EngngModel13solveYourselfEv + 798
  4   liboofem.dylib                      0x000000010af6c865 _ZN5oofem16StaticStructural13solveYourselfEv + 21
  5   oofem                               0x000000010a7a3d15 main + 8869
  6   libdyld.dylib                       0x00007fff58a59145 start + 1
Total 1 error(s) and 0 warning(s) reported
oofem exit code 1
engr2-14-136-dhcp:4 OOFEM Yige$ 

I tried with several different combinations and change the number of steps, but it seems that I can use either only negative values or only positive values in f(t) array so that I can get some solutions.
Could you tell me why?

Thank you very much!

Post's attachments

my_planestrain_ring_inter 8.77 kb, 3 downloads since 2017-10-30 

You don't have the permssions to download the attachments of this post.

Re: Question about PiecewiseLinFunction: No success in solving problem

Hi,

Could anyone help me? I'm still stuck on this code. I don't understand why when I use PieceWiseFunction, the values in f(t) should not change the sign. Once I use an array with both positive and negative values, there is no success in calculation.

Thank you very much!

3 (edited by nitramkaroh 08-11-2017 10:03:13)

Re: Question about PiecewiseLinFunction: No success in solving problem

Hi, I don't have much experience with interface elements, but it seems that the stiffness of your interface material is too high leading to problems when you change the sign of the loading. It is converging with Kn equal to 20e7.

Edit: You can also try another interface material like CohesiveInterfaceMaterial.