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Hello everyone,

I am currently writing a UMAT for non-linear viscoelastic materials. In order to do some verifications,

I need to be able to customize the time incrementation scheme. For example, the first increment would 

have a time step of 1E-5s while the other increments would have constant time step of 1E-2s. I know this is not a

very straightforward problem, but I really need to be able to do that. I am currently trying to combine my UMAT with other subroutines

Hello, I would like to know under what situation will a stiffness matrix in a FEM problem become non-symmetric? Is there any good reference to this topic? Thanks.

hey there,

please, how can I define the mass for implicit dynamic analysis (i.e; seismic loading) ???

My material is C3D8 if this information is usefull! 

Hi,

Is there a place I can find explained examples or tutorials on how to model user defined creep in ANSYS?



 

I need to follow the creep law __>      effective creep strain (e at time t) = S. T. e^(-H)

S=(a0)^t.(sigma)^(a1) ;     T = t^(a2)+(a3).t^(a4)+(a5)t^(a6)   ; H = (a7)/[(theta)+273.16]

a0 to a7 are material constants.

I have the experimental data and tried to fit the curve in Ansys to obtain the material constants. 

i want to model a single pile whith surrounding soil in abaqus. my problem is about:

1)step mudulus: how i must define step mudulus to obtain a time history and spectral(frequency) displacement response.

2)how i can apply elcentro spectrum in abaqus. i dont know nothing about this.

thanks

Any one knows how to buy the MPCCI software?

Greetings,

I'm working on thermal analysis of concrete filled steel tube columns.

I used all the guidance I could get  from the research papers, but I still didn't get the results I want.

In fact, all the job analysis I run ended up abrupted. 

I attached my abaqus work for your kind attention and perusal. 

Any suggestions and tips that might help me overcome my problem is more than welcome. Perhaps I could get some pointers whict part in my analysis is missing.

Thank you.

My work links:

sir/madam,

                i have modelled a curved section with one end fully constrained and to other end applied pull load, i am getting result in cylindrical co-ordinate system can i see the results in cartesian co-ordinate system 

i am a student of Msc in structural engineering. currently i have been involved in the research of "shear behaviour of RCC beam column joint ".