Meshing Problem 2 (!!URGENT!!)

[MusZip]

Hello,

This post is my second one. In fact, it is one of the trials for the analysis a simple w-shapeed profile using "solid element". At this time, I utlize the partition command in order to merge the flange and web parts (see cantilever_I_beam_BilinIMK_Solid_2.rar). The main reason behind this is unfortunately related to the "union" command because I can not obtain a structured hexagonal (regular brick) form.
However, at this trime, again I get a error mesage as "invalid type element usage" (see error_cantilever_I_beam_BilinIMK_Solid_2.PNG). I think tha this reason is arisen from the unregulzarized node mesh.

what must I do in order to analyse a simple cantilever solid beam with w-section?

[STKO Team]

At this time, I utlize the partition command in order to merge the flange and web parts (see cantilever_I_beam_BilinIMK_Solid_2.rar)

What do you mean by "partition" command?

The main reason behind this is unfortunately related to the "union" command because I can not obtain a structured hexagonal (regular brick) form.

Of course, the union command removed the internal faces of the solids. A structured hexa mesh can only be done for volumes with 6 faces (each face should have 4 sides).
Use the "merge" command instead (unlike the union, it keeps the internal faces)

Finally, the error about the invalid element type, is due to the fact that you assigned the ElementProperty (stdBrick requires a hexa with 8 node) not only to the volumes of the geometry, but also to its boundary faces/edges (and they are not meshes with 8 nodes!)

[MusZip]

Hello,

Thanks for your reply. I am really sorry for my delayed reply.

I try to re-model this simple system considering your advices which was mentioned in both current post and the previous one (see cantilever_I_beam_BilinIMK_Solid_new.rar). In this new model, firstly, the solids elements are merged and then a control node is selected and connected with the upper faces. Then, although this interaction is defined in the section of "conditions" through a number of options including "beamSolidCoupling", at the each time of these trials, an error "invalid type element usage" is generated. As if there exists an inconsistence between the generated degree of freedom and element degree of freedom.

I can not find out which step to be ignored during modelling this system.

[STKO Team]

Check this:

cantilever_I_beam_BilinIMK_Solid_new.zip

(137.36 KiB) Downloaded 81 times

It seems that you didn't read the previous reply

Finally, the error about the invalid element type, is due to the fact that you assigned the ElementProperty (stdBrick requires a hexa with 8 node) not only to the volumes of the geometry, but also to its boundary faces/edges (and they are not meshes with 8 nodes!)

The element should be assigned only to the sub-solids of your geometry (not to the boundary faces/edges).
Use sub-selection for this:

only solids.png (388.44 KiB) Viewed 832 times

There were also other small mistakes I fixed (material not assigned to solids, no selection set for displacement control analysis).

Finally I don't really understand what you are trying to do with that equalDOF, and there is no load, so the Displacement Control Analysis cannot start.

I would suggest you to start from the basics of STKO and OpenSees using the getting started webinar series

[MusZip]

Dear STKO-team,

Firstly, thanks for your valuable support. Also, I would like to thank you for your patience.
I am really glad for being you here since your mission broadens a new horizon on Opensees program.

Please, you admit my sorry due to my newbie questions. But, please be sure that these questions are asked to close any open door in the submitted problems. Because, I strive to prepared the model in a way of using the similiar logic as in the commercial programs, ANSYS, ABAQUS and etc. Thus, unfortunately, this boring situations are inevitably occured.

I am happy to give you an information about being solved the problem through your instructions.

[STKO Team]

Let me show you how I would do it.
Let's assume you want a cantilever beam (fixed on one side, and a constant shear force on the other side)
You have 2 options:

1. Either assign a constant Face-Force (stress) so that this value times the area is equal to the total force on that face
2. Or create a control node (similar to the reference point in Abaqus) and link it to the face of the beam with a beam-solid-coupling

In this example, I used option 2.

cantilever_I_beam_BilinIMK_Solid_new.zip

(300.04 KiB) Downloaded 58 times