X Tension Bars with split bars

[eng_leandromartins]

Hello everybody,

Is there any way to create these diagonals in X like this in the image below?

Note that it is made up of 3 bars (179, 180 and 51). But as you can see, we have an instability problem at node 6, which is the node where the bars cross.
These bars are only in tension.

[Stephane.kapetanovic · Accepted solution]

Hi @eng_leandromartins 

Probably, using tension only, best is not to split the diagonals. could you share your model?

Best Regards

[eng_leandromartins]

These bar are tension.

I normally do it without dividing the bars, but I wanted to simulate what it actually looks like in reality, after being manufactured.

[Rafacascudo · Accepted solution]

@eng_leandromartins 

  What @Stephane.kapetanovic suggested is the best solution.

  But if you want to simulate 100% the "real thing" ,then you have to forget about tension only bars because such thing does not exist in the real world.

  To simulate as close as possible to the real world ,use regular bars that can have ,axial , shear and moment in all directions with elastic releases in all 6 directions. It is even possible to release compression using regular bars
  Much more work compared to the optimal proposed solution by @Stephane.kapetanovic , but ,if done right , it will be possible to divide the bar and not get instability warnings. In the end ,you will get the very same axial tension force on the 2 methods and also 5 more neglegible forces and moments using the regular bars.

   Structural modelling ,very often, does not mean that you have to exactly represent what real structure looks like . You just have to have in mind that sometimes  compromises have to be made so the model represents and outputs only what is really important to the safety of the structure.

@eng_leandromartins  , are you Brazilian?

[eng_leandromartins]

Thanks so much @Rafacascudo!

I already imagined that I would have to do it this way.
When I said I wanted to simulate reality, I expressed myself badly.
In fact, I wanted to do the same thing that I sometimes did in SAP2000, because there is no this problem with instability in these situations.

Sim sou brasileiro! 

[Simau · Accepted solution]

@eng_leandromartins 

As these members are in tension only, there are not splitted. In the eal world there is a plate that join them.

[Rafacascudo]

   Truss bars , tension or compression only are just regular bars with every translation/rotation released except Ux ( axial force).

This way it can only exist if connected to a node(support or another bar) that is fully rigid (not released),otherwise  this truss bar will become unstable and the program will report an instability warning.

Tb brasileiro aqui , Rio de Janeiro . Bem vindo!