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Dear all,



I have a problem now:



I simulated indentation on a elastic-plastic model with a rigid
indenter, the elastic ideal plastic with von mises stress model in



ABAQUS is used. A contact pair is applied to calculate the contact between the indenter and the sample.



The problem is that the obtained the force-displacement data in the loading part, which contains the plastic deformation

is not smooth, but in the unloading part is smooth. But if a model

Hi all

I am doing a Riks analysis and this error of too many attempts for increment came up in the 47 th increment while the whole is 100  , I  guess that my mesh is coarse , so when my load is small , i face this error , is this right ? that in Riks analysis the loads should be big enough to show the nonlinearity in NLgeometric elastic structures ?

Hi All

If I have three shells that are joint to eachother , and i have to make a composite lay-up out of them , if I have the stiffness matrix of each shell ,  6x6 matrices ,  to build up this composite lay-up , how to I assign the matrices to build the global stiffness matrix ?  does each of the stiffness matrices of the shells counted as a [Q] , compliance matrix ?

Anyone has an example using this subroutine ? 

I have implemented a test pgm as per user manual but i cannot get it to work.

Thanks.  

I have an eigenvalue solver, subspace iteration, that can get only positive eigenvalues. I have a problem (K - lambda M)u=0 that has pairs of eigenvalues +/- lambda. How can I transform the eigenvalue problem for the solver to search for lambda^2 rather than lambda?

Hello all,

I am interested in using a finite element software in a supercomputer setting (i.e. bluegene, cray, etc.). Does anyone have experience running finite element solutions on massively parallel supercomputers? What solvers are most amenable to such a task?

 -Ryan

hello everyone

First of all accept my apologize for bad english writing...

I'm a abaqus user and write script by python,,,

For geting result from ODB file i need to get the step duration time and each fram time in step from output file but a couldn't make it....please give me advice how to do that..thank you in advance...

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Hi

Sorry in advance, but this will be a long story...
Thank you for taking the time to look at it! :)

I have a 2D model that worked fine until a couple of
days ago where I tried changing the mesh a bit. Now when I try to run it aborts
calculation and gives some of the following errors:

- There are 14 unconnected regions in the model.

Greetings ,

i had successfully running my model in the step with dynamic (explicit).

BUT once i change my model with step in static (standard) then the job stop running in the half way with the error of

"the system matrix has 3 negative eigenvalues"

how can i solve this problems??

 thanks for the help.  

Hi all,

 I want to write a matlab based code that will be able to describe material behaviour under uniaxial loading. So what I am interested in is the plasticity of a material. I want the code to be able to represent material behaviour after yielding and also cyclic loading.