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Dear ABAQUS Users,

I am trying to assign the initial stresses for a region in my model using the SIGINI subroutine. I learned some fortran programming skills the last week and I managed to open the file where the stresses that I retrieve from an Abaqus analysis and assign these stresses in Array using fortran commands.

Now I am stuck with the writing of the SIGINI subroutine where I have the corresponding stresses that I store in my Array to the corresponding NOEL and NPT.

Hi all,



Could someone explain, please, how the following expression can be written in component notation according to summation convention?



a^{kj};k + G^j_{km} a^{km} + G^k_{km} a^{mj}



it is the case of general tensors (non Cartesian)

indices k, j, m take values 1, 2, 3

G^j_{km} is Christoffel symbol of the second kind

; denotes partial differentiation (it is not covariant differentiation)



The first term is written a^{1j};1 + a^{2j};2 + a^{3j};3  

hi everyone,           i attached FRP strip and u-wraps to the concrete beam. i simulate it in ansys using shell 99 for FRP strip and uwraps. but i have a problem that the beam behaves as if the FRP does not work, and the failure load is as the same for the beam without FRP. however i merged the joints between FRP strip and uwraps and the concrete joints. i hope if somenone knows the reply, i need this reply very soon.  thank you so much for cooperation.

Hi everyone,

well, im glad i found this forum dedicated to abaqus users. i'm just a
rookie, got in touch with abaqus in less than a month for my thesis.
hope you can help in my first big struggle.

im modeling a nut and a bolt thread in 2d, they should move towards
eachother and upon contact they should crash past eachother. i went
through all the modules quite ok. i run the job, it is successful. in
the visualization window, when i try to see the deformation of the
threads the following message is displayed:

I am using Feap 7.5 to test a pipe (subjects to internal pressure) that has different mechanical property in radial direction (0R), circumferential direction (0T) and longitudinal direction (0Z). Originally, mechanical properties are given according to the (0R,0T,0Z) axes. I was required to use the hexahedral element (brick) to simulate this problem. Could you show me how to use the mechanical properties according to the (0R,0T,0Z) axes in the global axes (0X,0Y,0Z).

Thank you in advance.

NH NGUYEN.

Hi

I'm relatively new to abaqus. When I assembled an ran my model, all the interacting surfaces seemed to push apart from one another. See below:

Before 

http://h.imagehost.org/0195/Error-1.jpg

After

http://h.imagehost.org/0380/Error-2.jpg

 I apologize if this is a stupid question, but I really need to meet a deadline. Any replies will be greatly appreciated!