After activating the RF‑PIPING add‑on module, a new toolbar is available in RFEM and the project navigator and tables are extended. The piping system is now modeled in the same way as the members. Pipe bends are defined simultaneously by tangents (straight pipe sections) and radius. Thus, it is easy to subsequently change bend parameters.
It is also possible to extend the piping subsequently by defining special components (expansion joints, valves, and others). The implemented libraries of structural components facilitate the definition.
Continuous pipe sections are defined as sets of piping systems. For piping loads, member loads are assigned to the respective load cases. The combination of loads is included in piping load combinations and result combinations. After the calculation, you can display deformations, member internal forces, and support forces graphically or in tables.
Pipe stress analysis according to standards can then be performed in the RF‑PIPING Design add‑on module. You only need to select the relevant sets of piping systems and load situations.
Before the calculation starts, you should check the input data using the program function. Then, the CONCRETE add‑on module searches the results of relevant load cases, load as well as result combinations. If these cannot be found, RSTAB starts the calculation to determine the required internal forces.
Considering the selected design standard, the required reinforcement areas of the longitudinal and the shear reinforcement as well as the corresponding intermediate results are calculated. If the longitudinal reinforcement determined by the ultimate limit state design is not sufficient for the design of the maximum crack width, it is possible to increase the reinforcement automatically until the defined limit value is reached.
The design of potentially unstable structural components is possible using a nonlinear calculation. According to a respective standard, different approaches are available.
The fire resistance design is performed according to a simplified calculation method in compliance with EN 1992‑1‑2, 4.2. The module uses the zone method mentioned in Annex B2. Furthermore, you can consider the thermal strains in the longitudinal direction and the thermal precamber additionally arising from asymmetrical effects of fire.
Graphical input of piping systems and piping components
Illustrative visualization of piping systems and piping components in RFEM graphic window
Comprehensive libraries for piping cross‑sections and materials
Comprehensive libraries for flanges, reducers, tees, and expansion joints
Consideration of piping structure (insulation, lining, tin‑plate)
Automatic calculation of stress intensification factors and flexibility factors
Specific piping action categories for load cases
Optional automatic combinatorics of load cases
Consideration of material properties (modulus of elasticity, coefficient of thermal expansion) either during operating temperature (default setting) or during reference (assembly) temperature of material
Consideration of strain and uplift due to pressure (Bourdon effect)
Interaction between the supporting structure and the piping system
The global calculation assigns the stiffness determined by means of the selected composition and the glass geometry to each surface. Then, the calculation proceeds using the plate theory. It is possible to select whether the shear coupling of layers should be considered.
In the case of the local calculation, you can further specify 2D or 3D calculation. Two-dimensional calculation means that the single-layer or laminated glass is modeled as a surface, whose thickness is calculated on the basis of the selected structure and glass geometry (using the plate theory). Similarly to the global calculation, you can optionally consider shear coupling of layers.
The 3D calculation uses solids in the model to substitute each composition layer. This way, the results are more accurate, but the calculation may take more time.
It is possible to model insulating glass only if local calculation is selected. The gas layer is always modeled as a solid element, so it is necessary to design individual insulating glass parts independently of the surrounding structure. The ideal gas law (thermal equation of state of ideal gases) is considered for the calculation and the third-order analysis.
Structures are entered as 1D, 2D, or 3D models. Member types such as beams, trusses, or tension members facilitate the definition of member properties. For modeling surfaces, RFEM provides For example, the types Standard, Orthotropic, Glass, Laminate, Rigid, Membrane, and so on, are available.
Furthermore, RFEM can select among the material models Isotropic Linear Elastic, Isotropic Plastic 1D/2D/3D, Isotropic Nonlinear Elastic 1D/2D/3D, Orthotropic Elastic 2D/3D, Orthotropic Plastic 2D/3D (Tsai-Wu 2D/3D), and Isotropic Thermal -elastic, Isotropic Masonry 2D, and Isotropic Damage 2D/3D.