Overlapping structures - mass estimation error

Karamba3D calculates beam structures however it seems not to account for intersections such as depicted on attached figure. Results for mass and deflection seem conservative when compared with high fidelity methods. @cp1 @matttam Can you please help us? Thanks in advance.

Dear @edmaralino,
you need to intersect the lines prior to feeding them into the ‘LineToBeam’-component. In Karamba3D elements are connected only when they share a common node.
– Clemens

Dear @karamba3d @cp1

Thank you for your prompt reply. The curves and intersection points were proved to Karamba.

Is there a process in Karamba to “intersect the curves”? Please teach on how to intersect the curves.

Thanks again, Edmar


you can use the Line-Line-Intersection component ( https://manual.karamba3d.com/3-in-depth-component-reference/3.8-utilities/3.8.7-line-line-intersection)

You can refer to for a guide on how to set up your lists:

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Hello @matttam and @karamba3d ,
As per your recommendation, model was updated to work with lines instead of curves. However, as per figure attached, there is an issue with the node with the load. Note that the node is on the list of points of intersection calculated priorly with LineToBeam.

Basically, a list of lines is sent to LLInter and LSS is then sent to LineToBeam. Elem and Pts outputs from LineToBeam are then sent to Analyze.

I appreciate your support.

Kind regards, Edmar

Hi, you should make sure to flatten all your inputs in Assemble Model - you have multiple branches in your data structure. Then pts are not necessary unless you are working with specific indexes.

Hello @matttam

Thank you for your reply. Please refer to attached figures upon flattening the inputs in Assemble Model.

Hi @matttam @karamba3d,

I have attached the file with both options, curve and line, implemented. Note that option with line is not working properly. Note that the mass calculated is the same but I expected the mass to be much less.

Michell_karamba3D_Line_Line_Interpolation.gh (86.0 KB)

I appreciate your support and cooperation.

Kind regards,

Hi, what units are you working in? Karamba takes metres as the default units, and at the moment the entire structure is 1900m long.


Hello Matthew @matttam

Regarding your question on units, I followed @karamba3d recommendation to set units on karamba.ini file as per forum item Material units - #9 by karamba3d. Files regarding units are herein attached. Note that structure lenght shall be 1,9m long.

karamba.ini (14.3 KB)

Can you help with the overlapping trusses?

I really appreciate your support. Kind regards, Edmar

Hi karamba3d does not consider overlapping elements when considering weight, however with the lines intersected and in mm, the displacements seems realistic.