algorithmic modeling for Rhino



Karamba3D is a parametric structural engineering tool which provides accurate analysis of spatial trusses, frames and shells.

Current Version: 1.3.2 (July 9 2019)

Location: Vienna
Members: 1092
Latest Activity: Jun 30

Karamba3D is an interactive, parametric finite element program. It lets you analyze the response of 3-dimensional beam and shell structures under arbitrary loads.

Karamba3D is being developed by Clemens Preisinger in cooperation with Bollinger und Grohmann ZTGmbH in Vienna.

Download a free trial now! Licenses for educational or commercial purposes can be purchased at

downloads, manual: or

examples (for Karamba3D 1.3.2):

release notes:

scripting guide & examples:

repository with unit tests:

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


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


This grasshopper discussion forum is no longer maintained - please post all questions on the McNeel Forum. Thank you


Discussion Forum

Karamba - user problems 249 Replies

please post here in case of karamba problems !Continue

Tags: problems, faq, karamba

Started by Karamba3D. Last reply by Karamba3D Jun 21.

Column cross section sizing

I have created a simple building model with columns/beams and have tried to set up different models to see the impacts of different cross section sizes once I have changed the span size and some…Continue

Started by Anna Donaldson May 10.

Bending of columns 1 Reply

Hey, I want to simulate bending very thin straight columns under the weight of a slab(like in the image). What am I doing wrong? It just pushes the columns down.Continue

Tags: columns, bending, karamba

Started by Jan. Last reply by Janis May 5.

Karamba3D Joint Error 3 Replies

Hello. I’m trying to make scissor structure on grasshopper using karamba. When I want to  define joints in assembly, it gives me an error. How can I define connection of the elements with revolute…Continue

Started by Atefeh Edy. Last reply by Atefeh Edy Apr 24.

Comment Wall


You need to be a member of Karamba3D to add comments!

Comment by Karamba3D on April 13, 2020 at 9:44am

Dear all, please use the McNeel Forum (see to post your questions and not the comment wall.

-- Clemens

Comment by Ondřej Rejnek on April 9, 2020 at 6:46am

Hello, I am creating a parametric model of shell truss for evolutionary optimization. When applying Mesh Brep component on my model, the resulting mesh gets weirdly distorted and broken around the edges. Do you know what might be causing this issue? Here is my GH

Comment by jiaxing on March 22, 2020 at 9:16am

another questions about the initial strain load,  from the cases provide, for example,the beam with initial strain load  do not have shear force and bending monent. in my understand , pure axis force only  is much more safe then  shear force, bending moment, and axis force together(hope my understand is right)

not sure my understanding is right:  this initial load is the results of axis-force we want it inside and a load affect.

my question is, 1. in reality projects  where does this load come from? it is the results of load we want. then how to add this on?

2. if we can use initial strain load  to replace other loads, then how to transfer other loads with initial load. for example  the beam under gravity become an arch, but we want a pure axis force arch, no shear force,  then how to transfer gravity G=10 equals  initial strain load?

3 is there any case of projects use initial strain load help me understand? 

Comment by jiaxing on March 19, 2020 at 10:54pm

hi, clements, thank you very much for your answer.

I learn this case about mesh load  and have 3 questions

1. there are meshs and beam, but the mesh do not have material , only have load,  what is that?

2. the mesh is not attached to beam, how to understand it?

in my understand the case is , for examble, mesh is floor , have dead load or live load, then under floor is attached beam,  this floor and beam should have intersect part, then the load will transfer to the beam.   but here, they are seperate.

3, the mesh load is z-direction, but it turns a x-direction affect on beam, why

pls help,  i know you help alot already

keep safe from virus  hope vienna is ok

jiaxing lu 

Comment by Karamba3D on March 18, 2020 at 10:08am

Hi, Jiaxing,
the eigenmodes and eigenvalues result from the solution of the eigenvalue problem (see e.g. here) of the stiffnessmatrix S. The eigenmodes show in ascending order those deformation modes which the structure can take on most easily. The eigenvalues are the ratio between the internal forces and the corresponding eigenmode displacements.
The eigenvalues and eigenshapes as calculated in Karamba3D have nothing to do with stability or vibrations. For the buckling modes one has to solve the general eigenvalue problem which involves the stiffness matrix and the geometric stiffness matrix. For the vibtration modes it's the general eigenvalue problem involving the resultant stiffness and mass matrix.
-- Clemens

Comment by jiaxing on March 17, 2020 at 10:19am

hi, clements,  i read karamba manual again,  during that, the eigenmode and eigenvalues still troubles me to understand,  it seems to test vabration and get eigenvalues by eigenmode. 

what is the funcion of eigenmode, and what does the eigenvalue mean?

stability?  do the eigenvalues has standard to show whether it is safe or not?

sorry,  it seems a basic structure knowledges,  

Comment by riccardo foschi on February 11, 2020 at 2:39am

right sorry for that, and thanks

Comment by Karamba3D on February 11, 2020 at 2:03am

Hi, I am moving all discussion to the user problems page as the parallel discussion is cumbersome.

Comment by riccardo foschi on February 11, 2020 at 1:35am

It turns orange because I set one point as support two times (it's part of two groups of points one group fixes the Z movement the other one fixes every movement), but it shouldn't be a problem right? at least the dialog box says so.

Anyway the problem is similar if I decimate the mesh, I think it might be a problem of how do karamba calculate the thickness of the structure, in fusion I modelled the thickness myself in Karamba I didn't maybe it's that? however I think in fusion when he calculate the mesh he also adds inside edges to keep the two layers together when deforming, in karamba I don't think it does it am I wrong?

Comment by Karamba3D on February 11, 2020 at 1:27am

Hi Riccardo, there seems to be an issue with you definition as it turns orange. Also, may it be that your mesh is too coarse?


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