In the "Group of Imperfection Cases" imperfection case, you can enter several geometric imperfection cases. This allows you to carry out GMNIA analyses where several geometric imperfections have to be superimposed.
Go to Explanatory VideoFor stress-strain analyses, it is possible to define gray zones for nonrelevant value ranges in the result panel.
- Stability analyses for flexural buckling, torsional buckling, and flexural-torsional buckling under compression
- Import of the effective lengths from the calculation using the Structure Stability add-on
- Graphical input and check of the defined nodal supports and effective lengths for stability analysis
- Determination of the equivalent member lengths for tapered members
- Consideration of Lateral-Torsional Bracing Position
- Lateral-torsional buckling analysis of the structural components subjected to moment loading
- Depending on the standard, a choice between user-defined input of Mcr, analytical method from the standard, and use of internal eigenvalue solver
- Consideration of a shear panel and a rotational restraint when using the eigenvalue solver
- Graphical display of a mode shape if the eigenvalue solver was used
- Stability analysis of structural components with the combined compression and bending stress, depending on the design standard
- Comprehensible calculation of all necessary coefficients, such as the factors for considering moment distribution or interaction factors
- Alternative consideration of all effects for the stability analysis when determining internal forces in RFEM/RSTAB (second-order analysis, imperfections, stiffness reduction, possibly in combination with the Torsional Warping (7 DOF) add-on)
- Manual specification of critical component temperature or automatic determination of component temperature for desired duration
- A wide range of fire curves: standard temperature-time curve, external fire curve, hydrocarbon curve
- Manual adjustment of the essential coefficients for the determination of the steel temperature
- Consideration of hot-dip galvanizing of structural components for the determination of the steel temperature
- Results of a temperature-time diagram for the gas and steel temperature
- Fire protection cladding as a contour or a box cladding with temperature-independent materials can be considered when determining the temperature
- Design of members made of carbon steel or stainless steel
- Cross-section design checks and stability analyses (equivalent member method) according to EN 1993‑1‑2, Clause 4.2.3
- Design checks of the cross-sections of Class 4 according to EN 1993‑1‑2, Annex E.
The design checks for the members you have selected are carried out taking into account the governing component temperature. You can perform the cross-section design checks and stability analyses according to EN 1993‑1‑2, Section 4.2.3, in the Steel Design add-on. All reduction factors and coefficients that are necessary are stored accordingly and are taken into account when determining the load-bearing capacity.
The effective lengths for the equivalent member design are taken directly from the strength entries. You don't need to enter them again.
In each design, perform the cross-section classification first. For the cross-sections of Class 4, the design is performed automatically according to EN 1993‑1‑2, Annex E.
Compared to the RF‑/TIMBER Pro add-on module (RFEM 5 / RSTAB 8), the following new features have been added to the Timber Design add-on for RFEM 6 / RSTAB 9:
- In addition to Eurocode 5, other international standards are integrated (SIA 265, ANSI/AWC NDS, CSA O86, GB 50005)
- Design of compression perpendicular to grain (support pressure)
- Implementation of eigenvalue solver for determining the critical moment for lateral-torsional buckling (EC 5 only)
- Definition of different effective lengths for design at normal temperature and fire resistance design
- Evaluation of stresses via unit stresses (FEA)
- Optimized stability analyses for tapered members
- Unification of the materials for all national annexes (only one "EN" standard is now available in the material library for a better overview)
- Display of cross-section weakenings directly in the rendering
- Output of the used design check formulas (including a reference to the used equation from the standard)
- Automatic generation of FE analysis models: The add-on automatically creates a finite element model (FE) of the steel connection in the background.
- Consideration of all internal forces: The calculation and design checks include all internal forces (N, Vy, Vz, My, Mz, MT) and are not limited to planar loading.
- Automatic load transfer: All load combinations are automatically transferred to the FE analysis model of the connection. The loads are transferred directly from RFEM, so manual data input is not necessary.
- Efficient modeling: The add-on saves you time when modeling complex connection situations. You can also save the created FE analysis model and use it further for your own detailed analyses.
- Extensible library: An extensive and extensible library with predefined steel connection templates is available.
- Wide applicability: The add-on is suitable for connections of any type and shape, compatible with almost all rolled, welded, built-up, and thin-walled cross-sections.
- Automatic consideration of masses from self-weight
- Direct import of masses from load cases or load combinations
- Optional definition of additional masses (nodal, linear, or surface masses, as well as inertia masses) directly in the load cases
- Optional neglect of masses (for example, mass of foundations)
- Combination of masses in different load cases and load combinations
- Preset combination coefficients for various standards (EC 8, SIA 261, ASCE 7,...)
- Optional import of initial states (for example, to consider prestress and imperfection)
- Structure Modification
- Consideration of failed supports or members/surfaces/solids
- Definition of several modal analyses (for example, to analyze different masses or stiffness modifications)
- Selection of mass matrix type (diagonal matrix, consistent matrix, unit matrix), including user-defined specification of translational and rotational degrees of freedom
- Methods for determining the number of mode shapes (user-defined, automatic - to reach effective modal mass factors, automatic - to reach the maximum natural frequency - only available in RSTAB)
- Determination of mode shapes and masses in nodes or FE mesh points
- Results of eigenvalue, angular frequency, natural frequency, and period
- Output of modal masses, effective modal masses, modal mass factors, and participation factors
- Masses in mesh points displayed in tables and graphics
- Visualization and animation of mode shapes
- Various scaling options for mode shapes
- Documentation of numerical and graphical results in printout report
- Deformation analyses of reinforced concrete surfaces without or with cracks (state II) by applying the approximation method (for example, deformation analysis according to ACI 318-19, 24.3.2.5 or EN 1992‑1‑1, Cl. 7.4.3 )
- Tension stiffening of concrete applied between cracks
- Optional consideration of creep and shrinkage
- Graphical representation of results integrated in RFEM, such as deformation or sag of a flat slab
- Clear numerical result display in the detail dialog box
- Complete integration of results in the RFEM printout report
Have you carried out the design successfully? The results of the deformation analysis are now listed in clearly arranged output tables or detailed dialog boxes with info text. The program shows you all intermediate values in a comprehensible manner. Graphical representation of design ratios and deformation in RFEM allows you for a quick overview of critical areas.
Due to the results output of the design checks with all intermediate results, you can follow the calculation to the smallest detail. The complete integration of results in the RFEM printout report ensures that you obtain verifiable structural design.
- Stability analyses for flexural buckling, torsional buckling, and flexural-torsional buckling under compression
- Import of the effective lengths from the calculation using the Structure Stability add-on
- Graphical input and check of the defined nodal supports and effective lengths for stability analysis
- Lateral-torsional buckling analysis of the structural components subjected to moment loading
- Depending on the standard, a choice between user-defined input of Mcr, analytical method from the standard, and use of internal eigenvalue solver
- Consideration of a shear panel and a rotational restraint when using the eigenvalue solver
- Graphical display of a mode shape if the eigenvalue solver was used
- Stability analysis of structural components with the combined compression and bending stress, depending on the design standard
- Comprehensible calculation of all necessary coefficients, such as the factors for considering moment distribution or interaction factors
- Alternative consideration of all effects for the stability analysis when determining internal forces in RFEM/RSTAB (second-order analysis, imperfections, stiffness reduction, possibly in combination with the Torsional Warping (7 DOF) add-on)
- Stability analyses for flexural buckling, torsional buckling, and flexural-torsional buckling under compression
- Lateral-torsional buckling analysis of the structural components subjected to moment loading
- Import of the effective lengths from the calculation using the Structure Stability add-on
- Graphical input and check of the defined nodal supports and effective lengths for stability analysis
- Depending on the standard, a choice between user-defined input of Mcr, analytical method from the standard, and use of internal eigenvalue solver
- Consideration of a shear panel and a rotational restraint when using the eigenvalue solver
- Graphical display of a mode shape if the eigenvalue solver was used
- Stability analysis of structural components with the combined compression and bending stress, depending on the design standard
- Comprehensible calculation of all necessary coefficients, such as interaction factors
- Alternative consideration of all effects for the stability analysis when determining internal forces in RFEM/RSTAB (second-order analysis, imperfections, stiffness reduction, possibly in combination with the Torsional Warping (7 DOF) add-on)
This feature helps you with the load application. You can have the required loading applied incrementally. This option is particularly suitable for your calculations according to the large deformation analysis. Furthermore, you can easily perform post‑critical analyses in RFEM.
- Overall maximum response factors and critical nodes
- Resonant analysis (maximum response factor, RMS acceleration, critical node, critical frequency)
- Impulsive (transient) analysis (maximum response factor, peak acceleration/velocity, RMS acceleration/velocity, critical node, critical frequency)
- Vibration dose values for both resonant and impulsive analyses
Charts
- Response factor vs walking frequency
- Mass participation vs eigenmodes
- Velocity time history
In order to facilitate the data input, surfaces, members, sets of members, materials, surface thicknesses, and cross-sections are preset. It is possible to select the elements graphically using the [Select] function. The program provides access to the global material and cross-section libraries.
Load cases, load combinations, and result combinations can be combined in various design cases.
The combination of surface and member elements and separate designs allows you to model and analyze only critical parts, such as frame joints, using surface elements. The other parts of the model can be designed using member analyses.
The form-finding function can be activated in the General Data dialog box, Options tab. Prestresses (or geometrical requirements for members) can be defined in the parameters for surfaces and members. The form‑finding process is performed by calculation of an RF‑FORM‑FINDING case.
Steps of the working sequence:
- Creation of a model in RFEM (surfaces, beams, cables, supports, material definition, and so on)
- Setting of required prestress for membranes and force or length/sag for members (for example, cable)
- Optional consideration of other loads for the form-finding process in special form‑finding load cases (self‑weight, pressure, steel node weight, and so on)
- Setting of loads and load combinations for further structural analyses
RF-CONCRETE Surfaces
The nonlinear calculation is activated by selecting the design method of the serviceability limit state. You can individually select the analyses to be performed as well as the stress-strain diagrams for concrete and reinforcing steel. The iteration process can be influenced by these control parameters: convergence accuracy, maximum number of iterations, arrangement of layers over cross-section depth, and damping factor.
You can set the limit values in the serviceability limit state individually for each surface or surface group. Allowable limit values are defined by the maximum deformation, the maximum stresses, or the maximum crack widths. The definition of the maximum deformation requires additional specification as to whether the non-deformed or the deformed system should be used for the design.
RF-CONCRETE Members
The nonlinear calculation can be applied to the ultimate and the serviceability limit state designs. In addition, you can specify the concrete tensile strength or the tension stiffening between the cracks. The iteration process can be influenced by these control parameters: convergence accuracy, maximum number of iterations, and damping factor.
In RX-TIMBER Brace, the following settings for the calculation can be made:*Selection of the designs to be performed
- Determination of displaying support forces and deformations
- Adjustment of recommended limit values for deformation analyses in the ultimate and the serviceability limit state design
- Free definition of parameters for the fire resistance design performed according to the simplified method
- Consideration of material nonlinearities (failing members)
You can define the design type to be performed in the Control Parameters window.
The cross-section resistance design analyzes tension and compression along the grain, bending, bending and tension/compression as well as the strength in shear due to shear force.
The design of structural components at risk of buckling or lateral buckling is performed according to the Equivalent Member Method and considers the systematic axial compression, bending with and without compression force as well as bending and tension. Deflection of inner spans and cantilevers is compared with the maximum allowable deflection.
Separate design cases allow a flexible analysis for selected members, sets of members, and actions, as well as for the individual stability analyses. such as stability analysis, load duration in case of fire, member slendernesses, and limit deflection can be adjusted as desired.
In RX-TIMBER Frame, the following calculation settings are available:
- Design of ULS, SLS, and/or fire resistance Selection of designs to be performed
- Determination of displaying support forces and deformations
- Adjusting the recommended limit values for the deformation analyses
- Free definition of parameters for the fire resistance design performed according to the simplified method
- Increasing bending stiffnesses for flat‑ended bending strains
Separate design cases allow for a flexible analysis of specific actions as well as for individual stability analyses. You can define the design type to be performed in the Control Parameters window.
The loading can be applied incrementally. The increment option is especially useful for calculations according to the large deformation analysis. For members, you can consider shear deformations and apply internal forces to a deformed or undeformed structural system. In addition, RFEM allows you to perform post‑critical analyses.
In RX-TIMBER Glued-Laminated Beam, the following calculation settings are available:
- Design of ULS, SLS, and/or fire resistance
- Selection of designs to be performed
- Determination of displaying support forces and deformations
- Adjusting the recommended limit values for the deformation analyses
- Definition of parameters for the fire resistance design performed according to the simplified method (optionally for F 30‑B, F 60‑B, F 90‑B, and user‑defined)
- Determination of tilting moment for pinned support
- Definition of support conditions for a beam
- Beam optimization by means of:
- Beam depth modification
- Modification of beam scene
- cross-section width
- Spacing of lateral supports
The design analyzes tension and compression along the grain, bending, bending and tension or compression, and shear due to shear force with and without torsion. Designs proceed at the level of design stress values. The design of structural components at risk of buckling or lateral buckling is performed according to the Equivalent Member Method and considers the systematic axial compression, bending with and without compression force as well as bending and tension.
The deflection in the characteristic and quasi-permanent design situations is determined for inner spans and cantilevers. Separate design cases allow for a flexible analysis of specific actions as well as for individual stability analyses. You can define the design type to be performed in the Control Parameters window.
Member and surface models created in RFEM are analyzed at a particular point by applying a unit load with the previously defined load magnitude and direction. The module determines the way the unit load affects the internal forces at the inspected point.
This simulation is represented graphically by an influence line or influence surface resulting from the load magnitude of the force or moment at the inspected model point. The graphical representation can be used for further analyses or to check the behavior of the model.
The RF-INFLUENCE add-on module determines the influence lines and surfaces of models containing beams and surfaces.
- Deformation analyses of reinforced concrete surfaces without or with cracks (state II) by applying the approximation method (for example, deformation analysis according to EN 1992-1-1, Cl. 7.4.3 )
- Tension stiffening of concrete applied between cracks
- Optional consideration of creep and shrinkage
- Graphical representation of results integrated in RFEM; for example, deformation or sag of a flat slab
- Numerical results clearly arranged in tables and graphical display of the results in the model
- Complete integration of results in the RFEM printout report
- Iterative nonlinear calculation of deformations for beam and plate structures consisting of reinforced concrete by determining the respective element stiffness subjected to the defined loads
- Deformation analyses of cracked reinforced concrete surfaces (state II)
- General nonlinear stability analysis of compression members made of reinforced concrete; for example, according to EN 1992-1-1, 5.8.6
- Tension stiffening of concrete applied between cracks
- Numerous National Annexes available for the design according to Eurocode 2 (EN 1992-1-1:2004 + A1:2014, see EC2 for RFEM)
- Optional consideration of long-term influences such as creep or shrinkage
- Nonlinear calculation of stresses in reinforcing steel and concrete
- Nonlinear calculation of crack widths
- Flexibility due to detailed setting options for basis and extent of calculations
- Graphical representation of results integrated in RFEM; for example, deformation or sag of a flat slab made of reinforced concrete
- Numerical results clearly arranged in tables and graphical display of the results in the model
- Complete integration of results in the RFEM printout report
- Deflection analysis of members and sets of members
- Graphical selection of single members and sets of members for design
- Limit deformations in reference to global, local, or resulting member directions
- Limit deformations in reference to lengths of single or continuous members, or specification of absolute deformation values
- Deformation analysis of extreme values from different actions
- Optional application of different design cases
- Free selection of length and deformation units independent of RFEM/RSTAB
- Integration of deformation analyses into the global RFEM/RSTAB printout report