# Boundary conditions

## Defining perioidc BC for 1 element elastic model for Biaxial pull in ABAQUS

For simplicity in understanding Perioidic BC in ABAQUS, I am trying to implement in a single element elastic model.

Material is elastic. There are two reference points defined Refpoint 1 for x-direction pull and Refpoint 2 for y-direction pull. Please find the attached picture for clarity in the model.

I have defined the equations for PBC in ABAQUS as below:

x1-x2+Refpoint1=0

y1-y2+Refpoint1=0

x3-x4+Refpoint1=0

y3-y4+Refpoint1=0

x2-x3+Refpoint2=0

y2-y3+Refpoint2=0

## "Plane Remains Plane" boundary condition in Abaqus

I am working on micromechanics modelling of steels. I need to implement  a "plane remains plane" kind of homogeneous boundary condition on some edges of my RVE of Dual Phase Steel. How can i do it by using *Equation option in Abaqus? I want to understand what all and how the nodes needs to be constrained? I am aware of "Planar Constraint" plugin in Abaqus, but some how it is not working for my RVE, so i want to go via the *EQUATION route. Any help would be greatly appreaciated.

Thanks ,

Danish

## SPH inlet & outlet boundary conditions for internal flow (dynamically creating/removing particles from computational domain)

Hi All,

I am trying to model internal flows using SPH in Abaqus. The current problem I am running into are the inlet/outlet boundary conditions. I need a way to be able to monitor the inlet and outlet zones and dynamically remove/create nodes (i.e., particles). Here is the process I have in mind.

## Edge crack boundary condition

Hi everyone

i'm working on modeling crack in plates and i'm a little confused about correct boundary condition of a single edge crack in a plate under tension! could you please tell me which corner should fixed and which one should defined as a roller???

i also attached a figure.

i tried 2 kind of BC for my problem:

1- node 1: roller (Ux=0) and node 3: fixed (Ux=Uy=0)

2- i only fixed node 2 (Ux=Uy=0)

and the stress intensity factor calculated by these BCs almost the same!!!

## [Abaqus]Residual Stress, Equlibrium step, Boundary conditions

Hello

Problem description: There is a simply supported(roller supports) shell element I-beam. There are lateral bracings too. All of this boundary conditions belongs to the Riks step(always last step in analysis).

Question: I have implemented triangular residual stresses by SIGINI subroutine, but I'm not sure what boundary conditions set up in preliminary equlibrium step. Should I include all of the lateral bracings in this step or maybe only roller support?

Thank You

## Extracting boundary conditions from output database (odb) file using ABAQUS scripting

Hi,

I am familiar with abaqus python scripting to create odb files and to extract nodal data from an output database (odb) file in ABAQUS. I would like to know whether it is possible at all, to extract the boundary conditions from an odb file. I guess that the boundary conditions are not stored in an odb file. But I am not sure. Any help in this regard ??

## boundary condition in 3d model

here is a simple question

I have modeled the reduced section of a  tensile test specimen in 3D (a simple cylinder; falt surface in x-y plane, length in z direction).  I applied a load on one flat surface of the cylinder, and put the opposite flat surface as a symmetry plane.

When I plot the result after the simulation of a tensile test, the cylinder moved in the direction perpendicular to the application of the load.  I was expecting it only to increase in length in the z direction.

Is there any other boundary conditions I should have considered?

## Boundary conditions given by functions

Hi,

I am using Abaqus/CAE to model the elastic behaviour of a plate. I would like to give/define a function to prescribe the displacement along one boundary, but Abaqus does not seem to accept this the way I'm doing it*. Can anyone help me out?

* on the Load module, I choose create boundary condition > displacement, then I select a boundary, select distribution user defined, and on u1 i type "x". I then get a message saying this is not accepted.