Robot Structural Analysis 2024 Freezes After Running Calculations

[roderickobeja]

Hello.

Not sure what is going on. I am working on a light frame timber structural analysis, inside RSA 2024. 

I have defined panels based on their elastic stiffness.

Between all beams and columns, I have included different panels to try to ensure that the FEM side of things correctly applies panel stiffnesses between beams and columns.

However, when I run the calculations, the calculation window freezes and does not progress.

What could I be doing wrong? How can I resolve this issue?

I also do not know if these files should be this large at almost 279 MB, is it normal. It apppears a small model. 

File is available here:

https://drive.google.com/open?id=1pi55b2bHtsbpq0RvyjscDohOGsGU5xrq&usp=drive_fs

@Stephane.kapetanovic + @Rafacascudo  +  @Simau  any help with this please?

Thank you. 

[Simau · Accepted solution]

Hi @roderickobeja 

The chosen mesh size of 1m is too large compared to the panels size.
I have remeshed your model with an adapted mesh size. For this type of structure it is not necessary to activate the earthquake in the vertical direction. I have therefore taken the earthquake only with X,Y direction in order to limit the number of Newmark combinations.
The updated model is attached.

https://we.tl/t-8i8GMfXPQK

[Rafacascudo · Accepted solution]

Do you really need to use orthotropic wood panels ? Will you need to know the forces acting on all these panels?

If not , use claddings to distribute the loads to the beams and columns.

If yes , you have tiny panels(roof  and walls) like 0,6mx0,5m and your assigned mesh size is 1,0m. You have bars crossing these panels diagonally. The mesh will be a mess.

1st rule on a complicated mesh like yours is do it before you run the model . And not all panels at once. Do it in parts and if it looks good , freeze them or the program will redo them all again when you run the model wasting unecessary.analysis time. Also If the roof is perfectly plane ,you can set just one big panel instead of dozens of small ones. Same for the walls

I opened your file in repair mode and then set a mesh size of 0,25m , meshed panel type by panel type

Froze them all. The model ran fast , but it was not enough to avoid inchorerent mesh warning.
You need to do it carefully . clicking on the mesh warning to check where the inchorerence is and then correct it

Check below ,these webinars(1 and 2) to learn good meshing practices

Build your Robot Structural Analysis IQ - YouTube

[roderickobeja]

Thank you, VERY MUCH, M. Agayr @Simau.

All well noted, and will improve as indicated. 

[roderickobeja]

Thank you for the kind thoughts and suggestions Rafael @Rafacascudo.

I will enjoy again the Build your Robot Structural Analysis IQ series https://www.youtube.com/playlist?list=PLY-ggSrSwbZqow_60fiqJwS69mg1nQMzk (1 and 2 and more). And also consider all else. 

The orthotropic wood panels, help me begin to understand how Robot understands things especially towrds trying to introduce thngs like CLT panels inside Robot, and loos liek the orthographic wood panels is a possibility. I defined panels between beams and columns because I assumend that maybe it improves how elastic stiffness is calculated, since surrently we have litte panels of between 9mm, 12mm, 22mm and 24mm where required and nail laminated at beams or columns, and I wianted to see if this smaller placements of panels improves elastic stiffness. But if defining it all as larger panels when in plane works, then I will do it like this since it is not exactly necessary to see actions, forces, stresses, moments in the panels. Mostly is to ensure a required elastic stiffness is correctly included in calculations. 

Largely I still need to learn what goes on in the backgroudn and define things better. 

THank you, again. 

Roderick Obeja