ricardojosedias
Structural
- May 29, 2014
- 1
Hi. I am trying to simulate a metallic frame, with a board of OSB connected to it by metallic fasteners.
I have done two different models:
First model: I used spring elements with linear behavior, with three degrees of freedom (translational directions at each node). I gave a high stiffness in order to consider the springs rigid.
Second model: I used connector elements with linear behavior, with type Cartesian (just to have translational CORM), and considering elasticity rigid.
When I observed the results for each model, I observed that in the second model (with connectors) I had displacements in the Z direction (out of plane displacement), like a twist of the panel (rotated around a vertical axis). Because I am applying only a horizontal force on the top of the metallic frame (not in the panel), I am not understanding why this happen.
With the spring elements the model behaves like it should, but I want to simulate nonlinear behavior of the spring, and for now I don’t know how to do it…I read the abaqus user manual, and made an input file, in order to insert the nonlinear behavior, but is not working. Does anyone knows how to put this in the input file correctly?
What I did, for the first degree of freedom, was: (excerpt of the input file)
*Spring,elset=Springs-1-spring
1, 1
*Nonlinear
0, 0
700, 0.001
900, 0.002
1010, 0.003
1040, 0.004
1150, 0.005
1200, 0.01
1100, 0.015
*Element, type=Spring2, elset=Springs-1-spring
1, OSB-1.21, Frame-1.13
2, OSB-1.18, Frame-1.14
3, OSB-1.15, Frame-1.15
4, OSB-1.12, Frame-1.16
5, OSB-1.9, Frame-1.17
6, OSB-1.3, Frame-1.18
7, OSB-1.2, Frame-1.19
Many thanks.
Regards,
Ricardo Dias.
I have done two different models:
First model: I used spring elements with linear behavior, with three degrees of freedom (translational directions at each node). I gave a high stiffness in order to consider the springs rigid.
Second model: I used connector elements with linear behavior, with type Cartesian (just to have translational CORM), and considering elasticity rigid.
When I observed the results for each model, I observed that in the second model (with connectors) I had displacements in the Z direction (out of plane displacement), like a twist of the panel (rotated around a vertical axis). Because I am applying only a horizontal force on the top of the metallic frame (not in the panel), I am not understanding why this happen.
With the spring elements the model behaves like it should, but I want to simulate nonlinear behavior of the spring, and for now I don’t know how to do it…I read the abaqus user manual, and made an input file, in order to insert the nonlinear behavior, but is not working. Does anyone knows how to put this in the input file correctly?
What I did, for the first degree of freedom, was: (excerpt of the input file)
*Spring,elset=Springs-1-spring
1, 1
*Nonlinear
0, 0
700, 0.001
900, 0.002
1010, 0.003
1040, 0.004
1150, 0.005
1200, 0.01
1100, 0.015
*Element, type=Spring2, elset=Springs-1-spring
1, OSB-1.21, Frame-1.13
2, OSB-1.18, Frame-1.14
3, OSB-1.15, Frame-1.15
4, OSB-1.12, Frame-1.16
5, OSB-1.9, Frame-1.17
6, OSB-1.3, Frame-1.18
7, OSB-1.2, Frame-1.19
Many thanks.
Regards,
Ricardo Dias.