frHinge Connection

[Pooyan]

Hello
I want to model the frame below in ANSYS, my problem is modeling the connections between elements.
I used BEAM3 for element type which default connection type between two elements is rigid.
As you see the middle connection has three elements joined.
My aim is the connection between 1 & 2 be rigid and 3 be hinged.
How can I model it?

http://freeebayimagehost.com/images/wbc2otwsupevow86ik.jpg

Best Regards
Pooyan

[Pooyan]

Hello
I want to model the frame below in ANSYS, my problem is modeling the connections between elements.
I used BEAM3 for element type which default connection type between two elements is rigid.
As you see the middle connection has three elements joined.
My aim is the connection between 1 & 2 be rigid and 3 be hinged.
How can I model it?

http://freeebayimagehost.com/images/wbc2otwsupevow86ik.jpg

Best Regards
Pooyan

[billywight]

Pooyan,

We will first need a larger diagram in order to make out the details of your question.

Also, look into beam end releases to release constrained DOF's at the joints.

[Pooyan]

Hi

Sorry, I don't get it! Larger diagram of what?

end beam releases such as BEAM44?
I used BEAM3 element for modeling, where can I find beam end releases?

I modeled a frame twice with all properties and dimensions but with two differences.
In second model
1) Add an extra node at joint after meshing
2) Used preprocessor > Coupling / Ceqn > Couple DOFs and pick the two coincident nodes and set Lab Degree-of-freedom label to ROTZ for rotation in Z direction
But the results of two modeling was exactly the same

Best
Pooyan

[billywight]

Pooyan,

I was making a joke as your diagram is rather gigantic...

I'm not sure what ANSYS calls it, but there is a way to "unfix" DOF's of beam elements. Try the help files.

[JDS]

I think it was created on a 3-wide monitor setup. That diagram must be 5000x2000 pixels

[Pooyan]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by billywight:
Pooyan,

I was making a joke as your diagram is rather gigantic... </div></BLOCKQUOTE>

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by JDS:
I think it was created on a 3-wide monitor setup. That diagram must be 5000x2000 pixels </div></BLOCKQUOTE>

http://fsae.com/groupee_common/emoticons/icon_smile.gif

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by billywight:

I'm not sure what ANSYS calls it, but there is a way to "unfix" DOF's of beam elements. Try the help files. </div></BLOCKQUOTE>

I searched for 'unfix' and the only result is TBFT command which is not related!

How about using COMBIN7 or CONBIN39 elements?

[billywight]

I don't know ANSYS terminology, but Algor calls it "Beam End Releases", Altair Calls it "Pins", etc. This is a screenshot of the Altair interface. The pins entry specifies free DOF, i.e. "15" would be free in X translation and Y rotation.

http://imageshack.us/photo/my-images/405/bar2w.png/

[Pooyan]

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Altair </div></BLOCKQUOTE>
OK
Thank you.

[Pooyan]

Any other idea?
http://fsae.com/groupee_common/emoticons/icon_frown.gif