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karamba

Karamba is an interactiv, parametric finite element program for shell and beam structures.

Current Version: 1.1.0 (February 13th 2015)

Website: http://www.karamba3d.com
Location: Vienna
Members: 512
Latest Activity: on Wednesday

karamba is an interactive, parametric finite element program. It lets you analyze the response of 3-dimensional beam and shell structures under arbitrary loads.

karamba is being developed by Clemens Preisinger in cooperation with Bollinger-Grohmann-Schneider ZTGmbH Vienna.

Download the free version for non-commercial use only. In case you want to purchase a commercial license contact us via info@karamba3d.com or read the manual for details.

 

download, manual:

http://www.karamba3d.com/downloads or

http://www.food4rhino.com/project/karamba

examples (require GH 0.9.0014):

http://www.karamba3d.com/category/examples/

update report/known bugs: 
http://www.grasshopper3d.com/group/karamba/page/new-features-and-bug-fixes

Here a beam structure based on stream-lines with bending moments:


 

More details, manual, examples and download ....

 

 

Discussion Forum

Stresses magnitude at space frame nodes 3 Replies

Hi everybody,1.I would like to know how to retrieve info on the magnitude of forces at the node points, as a result of 6 to 8 bars in compression or tension. Is there also a way to extract them at a…Continue

Tags: state, gravity, limit, ultimate, frame

Started by jm. Last reply by karamba on Wednesday.

Obtain stiffness matrix 1 Reply

Hi!As I understand it, Karamba includes the mass matrix and solves the eigenvalue for det(K-lambda*M)=0 in the 'eigen modes' and 'natural vibration' components. I need the eigenvalue for…Continue

Started by Camilla. Last reply by karamba on Monday.

Capital and punching 1 Reply

Hi, I am doing a practical work for students , the goal is to teach the operation of a mezzanine without beams . I want to show how it works and how it works with capital without capital , to learn…Continue

Started by Llordella Patricio. Last reply by karamba Feb 16.

Shell thicknesses, thermal loads, cross section optimization and groupIDs? 1 Reply

Hi, as far as I can tell, I cannot accomplish the following in Karamba:- apply a different thermal load for each shell element whilst grouping them for cross section optimization: I can only do one…Continue

Started by Diederik Veenendaal. Last reply by karamba Feb 12.

Comment Wall

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Comment by karamba on January 8, 2015 at 11:14pm

Leonardo:

in Karamba 1.0.5 the cross section optimization algorithm only considers normal forces for buckling. The next version (Karamba 1.1.0) takes full account of the EC3 formulas including lateral torsional buckling and interaction values according to annex B.

Best,

Clemens

Comment by Leonardo on January 8, 2015 at 3:53pm

Clemens, thanks for your quick answer.

I have carefully read the appendix and the way for calculating the buckling length is clear. However I have still one questions:

seems to be that adopting Eurocode3 (eq. 6.47) only the normal forces are compared with the critical buckling load. Am I right?

Can we want take into account both, bending and axial compression, as suggested by Eurocode3 (Eq. 6.3.3)? 

Many thanks,

Leonardo

Comment by karamba on January 7, 2015 at 11:02pm

Hi Leonardo,

the Cross Section Optimization component takes into account buckling for members (see the appendix of the Karamba manual). The assumed buckling length is the distance between two nodes that connect to more than three beams or to a support or double that distance in case one end is free. The buckling lengths can be set manually via the 'ModifyBeam'-component.
If you have 'huge' bending moments in your structure then buckling will have little effect on the result. 

Sometimes so called global buckling can govern a design (think e.g. of a compressed girder of a truss structure). In such cases one has to guess the buckling length or do a buckling analysis (which will be possible in Karamba 1.1.0). 

Best,

Clemens

Comment by Leonardo on January 7, 2015 at 3:56pm

Hi Clemens,

I need your help! I have a very simple curved geometry, like an arch, composed by several beams. This is a not funicular geometry and there are huge bending moments. I do not understand:

1) if the Cross Section Optimization component takes into account buckling for members in bending and axial compression (6.3.3 - Eurocode 3).  

2) if the buckling length corresponds to each beam or to the length of the whole arch or to the distance between supports (local or global buckling.

If instead of an arch, there is a more complex structure, i.e. an arch bridge with tendons and deck, what is the buckling length of the arch adopted by the Cross Section Optimization component?

Many thanks,

Leonardo

Comment by Llordella Patricio on October 22, 2014 at 12:40pm

Dear clemens

Thanks for the help, I just created a topic discussion and add any comments that we have done so far.

Best regards

Patricio

Comment by karamba on October 21, 2014 at 12:00pm

Dear Patricio,

try to increase the number of shell elements. As mentioned in the manual they are linear elements. A mesh that is too coarse leads to a response which is stiffer than the real structure. 

Best,

Clemens

P.S.: Could you please open a new discussion on the topic? These discussions are easier to find and follow for other people who face a similar problem.

Comment by Llordella Patricio on October 15, 2014 at 3:41pm

Dear clemens

I was doing a rough estimate of the deformation, and I can not achieve the same result with Karamba.
When I make a rough estimate of the result with Karamba beams and mine are very similar, I think the problem is when I connect the shell, because there are no similar results.

I sent the GH file, and an image of the calculation

The structure is concrete
The result I get is 0.58cm

thank you

Patricio

15-10-14%20Example.gh

Comment by Llordella Patricio on October 10, 2014 at 8:43am

Perfect, that is just what I needed, thank you very much for your help, I'll keep working and any questions write again, it is very useful for students to understand the structural performance.

best regards

Patricio

Comment by karamba on October 9, 2014 at 10:46am

You could use the 'Mesh Edges'-component to retrieve the naked edges and turn them into beams - see attached file: 91014Example1_cp.gh

Best regards,

Clemens

Comment by Llordella Patricio on October 9, 2014 at 8:35am

Hello, succeeds in creating the mesh to the slab, and built the beam segment, but when I see the deformations are not expected because the beam is deformed as the slab.

Thanks for the help

PS: maybe I'm using the program for a type of structure that is not the most appropriate, as I saw in the examples of other structures. But this type of structure is that students taught

best regards

Patricio

9-10-14%20Example%201.gh

 
 
 

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