FC-FEM-> Simulation von Stabwerkskonstruktionen

[bernd]

vor allem wir Mystran wie auch Calculx aktiv entwickelt.

[Laurie Hartley]

Hi Laurie, I am sure you remember this
https://forum.freecadweb.org/viewtopic.php?f=18&t=34638

Very interesting link (discussion), and a great extension of our discussion here.
Framework 2D+3D and MASTAN2 seem to be very powerfull tools...would be interesting to find out, whether FC drawings (2D..dxf??) could be imported.. maybe partly..
..we are on an exiting way of learning..

Hi cad1234 - what a coincidence. You and Thomas have been on my mind recently because over the past two years I have put a lot more time into the development of my system and have reached the stage of what do I do with it. I will PM you both tomorrow

[Laurie Hartley]

...
But: meshing the nodes is a problem

Modellierungsvorschläge gerne.

Here we are again Thomas & Cad1234:)

[bernd]

Das errinnert mit an ein Fachwerkbeispiel von Z88. Die zeit rennt das ist schon wieder 4 Jahre her . Wo ist die Zeit nur hin? Was haben wir die ganze zeit nur rumprogrammiert? https://forum.freecadweb.org/viewtopic. ... 21#p521021

Das oben sieht des sehr sehr ähnlich.

Eventuell kann das ja ma jemand als Solid oder mit einer anderen Software oder von Hand rechnen. Wäre gut zu wissen was ist richtig 64 mm oder 134 mm Verformung ...

bernd

[cad1234]

Laurie,
very impressive!!
A complete steels structure, with all details about the connections, including nuts, bolts, washers…
Great job!!
I tried to simulate your original model in FC-FEM and also in Mecway, but I failed.
Hope , Thomas will jump in too. He has much more knowledge and experience than I have.
Maybe, we have to go through your model with FC-FEM in separate steps?
Anyhow, this is also a great example about the practical use of FC-FEM, from my point of view.
Holger

[Laurie Hartley]

Eventuell kann das ja ma jemand als Solid oder mit einer anderen Software oder von Hand rechnen. Wäre gut zu wissen was ist richtig 64 mm oder 134 mm Verformung ...

bernd

Bernd - my model is actually a set up for a spaceframe with square hollow section members - I ran my tests using both of:-
Gerrit Wolsonks Framework programme
https://www.gerritwolsink.nl/ and
LISA Fem
https://lisafea.com/

Both gave almost identical results for displacement in Y direction. I have plenty of time on my hands so if someone can post the:-
Member type and sizes
Node spacings and
Loads and locations
I would be happy to run the tests using both programmes which would give you a comparison for calculix & z88.
However someone would have to do a sanity check on my input and results because I am not an engineer just an enthusiast

[cad1234]

Laurie,
very impressive!!
A complete steels structure, with all details about the connections, including nuts, bolts, washers…
Great job!!
I tried to simulate your original model in FC-FEM and also in Mecway, but I failed..maybe i did something wrong...
Hope , Thomas will jump in too. He has much more knowledge and experience than I have.
Maybe, we have to go through your model with FC-FEM in separate steps?
Anyhow, this is also a great example about the practical use of FC-FEM and how to handle such detailed models.... from my point of view.
Holger

[Laurie Hartley]

Laurie,
very impressive!!
A complete steels structure, with all details about the connections, including nuts, bolts, washers…
Great job!!
I tried to simulate your original model in FC-FEM and also in Mecway, but I failed.
Hope , Thomas will jump in too. He has much more knowledge and experience than I have.
Maybe, we have to go through your model with FC-FEM in separate steps?
Anyhow, this is also a great example about the practical use of FC-FEM, from my point of view.
Holger

Thank you for your compliment. I was able to run the FEM in Lisa (see above) which Mecway is a fork of. I was able to mesh the model in FreeCAD but it couldn’t run the computations - something like “cannot do multiple faces at this time”.

Looking forward to Thomas’ input. Could be a busy week in retirement coming up!

[cad1234]

Laurie, there is no retirement for creative people
Did you made the LISA simulation with the same level of details (nuts, bolts washers etc) or with a more simplified model?
Is there a way to send me the LISA file or upload it anywere?
I started with LISA and changed later to Mecway. Have both as full version.
I exported your FC-File as step-File and then tried to import in Mecway, which normally runs well, but not in this case, don`t know why..
Maybe you had a different workflow..?

[Laurie Hartley]

Laurie, there is no retirement for creative people
Did you made the LISA simulation with the same level of details (nuts, bolts washers etc) or with a more simplified model?
Is there a way to send me the LISA file or upload it anywere?
I started with LISA and changed later to Mecway. Have both as full version.
I exported your FC-File as step-File and then tried to import in Mecway, which normally runs well, but not in this case, don`t know why..
Maybe you had a different workkflow..

My model did not include the detailed node with plates bolts etc. I just created the array of node points and joined them together with 65 or 50 shs members.

My logic ;)was that the node assembly itself was stiff enough? The node itself probably needs a part by part fem analysis based on the results from LISA. Hello Thomas:)

I will post a link to the Lisa file later.

Bernd I seem to remember contacting z88 about 5 or 6 years ago when I started on this exercise. I could be wrong but I am fairly sure they told me that it wasn’t suitable for my 3D frame analysis.

In the long run my gut feeling is that Frame3DD will be the best option for this type of FreeCAD exercise