Form-Finding | Input
By activating the Form-Finding add-on in the Base Data, a form-finding effect is assigned to the load cases with the load case category "Prestress" in conjunction with the form-finding loads from the member, surface, and solid load catalog. Such a prestress load case thus mutates into a form-finding analysis for the entire model with all member, surface, and solid elements defined in it. The form-finding of the relevant member and membrane elements amid the overall model is carried out via special form-finding loads and regular load definitions. The form-finding loads describe the expected state of deformation or force after the form-finding in the elements, and the regular loads describe the external loading of the entire system.
RFEM 6 includes the Form-Finding add-on to determine the equilibrium shapes of surface models subjected to tension and members subjected to axial forces. Activate this add-on in the model's Base Data and use it to find the geometric position in which the prestress of lightweight structures is in equilibrium with the existing boundary conditions.
Compared to the RF-FORM-FINDING add-on module (RFEM 5), the following new features have been added to the Form-Finding add-on for RFEM 6:
- Specification of all form-finding load boundary conditions in one load case
- Storage of form-finding results as initial state for further model analysis
- Automatic assignment of the form-finding initial state via combination wizards to all load situations of a design situation
- Additionally form-finding geometry boundary conditions for members (unstressed length, maximum vertical sag, low-point vertical sag)
- Additional form-finding load boundary conditions for members (maximum force in member, minimum force in member, horizontal tension component, tension at i-end, tension at j-end, minimum tension at i-end, minimum tension at j-end)
- Material type "Fabric" and "Foil" in material library
- Parallel form-findings in one model
- Simulation of sequentially building form-finding states in connection with the Construction Stages Analysis (CSA) Add-On
- Why do the results in a modal analysis differ between the initial prestress and the surface load?
- Although I have modeled two identical structural systems, I obtain a different shape. Why?
- How is it possible to make factorized combinations of a dead load in the context of form‑finding?
- My aim is to mesh a circular hole plate in a mapped way. Is such a meshing possible in RFEM?
- It seems that the members stay not deformed after my RF-FORM-FINDING calculation. What did I wrong?
Can I export my cutting pattern?
- How do I model a tent roof with two cone tips?
- How do I model a suspended membrane roof structure with line supports?
- I would like to calculate and design "temporary structures." What do I need for this?
- I have already divided my membrane roof into individual surfaces. Can I quickly create a cutting pattern from these surfaces?
The Form-Finding add-on finds the optimal shape of members subjected to axial forces and tension-loaded surface models. The shape is determined by the equilibrium between the member axial force or the membrane stress and the existing boundary conditions.