Thus, membranes are considered separately and meshed automatically with triangles in comparison with all other elements. This global setting is covered in FE Mesh Settings.
Membrane Meshing
Mr. Niemeier is responsible for the development of RFEM, RSTAB, RWIND Simulation, and in the area of membrane structures. He is also responsible for quality assurance and customer support.
With the activated option 'Topology on Form-Finding Form' in Project Navigator - Display, the model display is optimized based on the form-finding geometry. For example, the loads are displayed in relation to the deformed system.
In RFEM, there is an option to couple surfaces with the stiffness types "Membrane" and "Membrane Orthotropic" with the material models "Isotropic Nonlinear Elastic 2D/3D" and "Isotropic Plastic 2D/3D" (add-on module RF-MAT NL is required).
This functionality enables simulation of the nonlinear strain behavior of ETFE foils, for example.
- Form-finding of:
- tension-loaded membrane and cable structures
- compression-loaded shell and beam structures
- mixed tension- and compression-loaded structures
- Consideration of gas chambers between surfaces
- Interaction with supporting structure (substructure design according to various standards)
- Surfaces as a 2D and members as a 1D element
- Definition of different prestress conditions for surfaces (membranes and shells)
- Definition of forces or geometrical requirements for members (cables and beams)
- Consideration of individual loads (self‑weight, inner pressure, and so on) in the form‑finding process
- Temporary support definitions for the form-finding process
- Automatic preliminary form-finding of membrane surfaces (more information...)
- Definition of isotropic or orthotropic material for structural analysis
- Optional definition of free polygon loads
- Transformation of form‑found shape elements into NURBS surface elements
- Possibility of combined form-finding by integration of preliminary form-finding
- Graphical evaluation of the new form using colored coordinates and inclination plots
- Complete documentation of the calculation including user-defined adaptive evaluation figures
- Optional export of the FE mesh as a DXF or Excel file