A Program of ZU.

 What:        SD2007+: Geometric nonlinear calculation of 2D truss  (Version 2013)


 Description: Calulation of 2D truss, using geometric nonlienar FEM. 
              Total Lagrange Formulation for big roation and small strain problem.  

 Updated:     09/04/2013
 Contact:     sicheng6699(AT)



Fig. Example of von Mises truss

Fig. Big Rotation of a truss


I have used Tcl/Tk for the GUI, Fortran for the calculation, Lapack-library for the numeric algorithms (linear equations, Eigenvalue).

Updated on 2013-04-09: The original Program with name of "SD2007 : Static and Dynamic Analysis for 2D-Frame (Version 2007)" don't exist. The googlepage was also shut down. Program is under development at the Institute for Structural Mechanics at University Stuttgart. There you can download and use it for educational purpose. And the language is only in German. [L1 ]

After several years as civil engineer, I am focusing on the geometric nonlinear calculation of 2D truss, maybe 2D frame also. Not sure how exactly to improve it. Just keep on trying. For Information there is a blog, about the new state. [L2 ]

And it on a testing stage, not ready for download or use. I'm ready for any discuss, and happy if you have some idea or feedback.

I updated this page in order to encourage people including me to keep on doing something that is interesting, e.g. using Tcl to accomplish some work.

ZU 2007-09-02:

Question 1 : If I want to do something with 3D-Framework, should I use 3dcanvas ? or hoco an homogeneous coordinates package? Something like:

RS: You might evaluate those (I haven't tried them much), but for wire frames it's very easy to define a function that transforms {x y z} coordinates in 3D space to {x' y'}.... The trickiest problem in my experience was detection and covering of hidden surfaces.

GS 2007-09-03 You should give a try to 3dcanvas ( ). This version written by DRH behaves like a 2D canvas. See the man page at [L3 ]. But you have to compile the package for the target platform and it depends on OpenGL.

ZU: Thank you for your advice. I will try.