How to model true offset beams in Sofistik

[muruep00]

I want to model a connection between two CHS and one SHS in FEM beam model.

How do I make the model to consider that the SHS does not reach the center of the CHSs, but only their exterior surface?

I attach two possible model solutions. I believe the first one is unrealistic since the length of the SHS is longer in the FEM model than in reality. Is the second option more accurate?

Thank you

 

[centondollar]

If you are using beam elements for e.g., a truss (CHS and SHS seem to imply this), this aspect of structural modelling does not matter in any practical applications. Connect the beams at their centroids. Your figure is also probably not to scale - make it to scale and read e.g., eurocode 3 guidelines to connection modelling for trusses to find out that rigid links at joints are usually unnecessary.

If you want to consider local effects (buckling, plasticity etc.), use shell elements or solid elements and apply boundary conditions that are similarly realistic (not infinitely stiff supports).

 

[muruep00]

If you are using beam elements for e.g., a truss (CHS and SHS seem to imply this), this aspect of structural modelling does not matter in any practical applications. Connect the beams at their centroids. Your figure is also probably not to scale - make it to scale and read e.g., eurocode 3 guidelines to connection modelling for trusses to find out that rigid links at joints are usually unnecessary.

No, its not a truss, elements have fixed connections.

If I connect beams at their centroids, not only I am using more material than in reality (and more self weight in the model), but am I not considering more section strength also?