Analysing beams

[SStraver]

Hi,


I've created aframe with Structural Members. This was my first time modelling with this feature, but it went pretty well. Now i've used this model to make an analysis with CosmosWorks using beams. The results are pretty good i guess, cause all the beams seem to be connected and the deformation is as expected.


The only problem I'm having is that I dont know how to interpret the results. I can chose these resulttypes:


1) Axial
2) Bending in Local direction 1
3) Bending in Local direction 2
4) Worst Case


The axial tensions I can understand, but the others I don't. In what direction are the bendingsand what do they mean with Worst Case?
I've done a precalculculation with PCFrame and i can say that the results are comparible with Bending in Local direction 2, the others, exept for axial show lots higher tensions.


Here a figure of the results in Bending direction 2:





I hope someone can help me. Btw im from Holland so excuse me if I've made a few mistakes. Please correct them if it really doesnt make sense,Ican only learn from it. But give priority to my question .


Thx in advance.


Sander.

 

[SStraver]

Uhm.. 40 views; 0 reply's. Does no one know the answer??

 

[Angstboy]

From this picture, it is very hard to interpret.For one, does this frame reflect some kind of real world problem? Or is it a mish-mosh of members placed in a fantasy array? If it is the latter - forgetaboutit. If you are trying to learn how to use a program, that's not the way to do it. Start with a simple structure so you can compare the program's results with results obtained by other means. Use reality based examples, preferably from textbooks that show worked out problems so you can get the feel for how the results are presented and can compare values. Work up to a problem like this.


If this is a reality based problem, all I can say is...good luck. Based on justwhat I can see in this view...haven't got a clue as to what to tell you.

 

[tva.amitava]

Hi

I am trying to analyze a CRANE boom. I have made the boom with 6 Parts. Each part is made by 3D lines and then by Weldmelts>Structural Member. I am uploading Part 3 image here.

I want to divide this beam using beam element and analyze. One member should be one element. Can anyone tell me how to do that. And also how to join the members together because when I try to analyze it in cosmos the mesh fails and shows my truss members are not connected. Is there an easy way to make the joints.

Thanks

Tava

 

[SStraver]

Hi,


I have succesfuly made analysis with my structure. THe best way to analyse it is with worst case. This combines the stresses and moments in all directions. And no, my model was not an imagination, but the real thing

Meshing beams is quite simple but your parts must be build the right way. What I asume you did is let all the structural members fit like it would in real life. But the key is to let all the sketch-lines connect (this may not always look good). Than you can be sure of a good mesh without missing joints. Cosmos will automaticly mesh it (in my model a mesh length of about 2x the thickness of a member).


Good luck!

 

[tva.amitava]

Hi

I have seen your models picture and thats why I am hopeful that my model can work too.

I joined the lines as i get from an auto cad design and in that design the lines do not intersect.

Here is my sketch.

I want to make sure if my process of designing the structure is alright or not.Is [weldmelts>Structural member] is correct method to make space frames.

Now where can I find the beam element in cosmos. what i can see is only solid mesh,surface mesh and mixed mesh. I am searching for beam element for 5 hrs.

Please help me with that.

Thanks

 

[SStraver]

The only reason I can think of why you cant select beam mesh is that your version of SW doesnt support it. I'm working with Office Premium 2007, with all the possible options and i c

 

[tva.amitava]

Thanks for reply. You are correct. I have checked with the Solid works people. They Said my version of Solid work (2006 Student version) does not support beam element. i need to upgrade to 2007.

I tried to coincide the joints. That works fine with surface type mesh and gave me an equivalent picture of yours structure.

Thanks

Tava