You have the option to perform the fire resistance design of surfaces using the reduced cross-section method. The reduction is applied over the surface thickness. It is possible to perform the design checks for all timber materials allowed for the design.
For cross-laminated timber, depending on the type of adhesive, you can select whether it is possible for individual carbonized layer parts to fall off, and whether you can expect increased charring in certain layer areas.
Did you know? In the Design Supports, you can now define fully threaded screws as transversal compression stiffening elements for the "Compression Perpendicular to Grain" design. In this case, the pressing-in and buckling of the bolts is analyzed.
Moreover, the design shear resistance is checked in the plane of the screw tip. The angle of dispersal can be considered as linear under 45° or nonlinear (according to Bejtka, I. (2005). Verstärkung von Bauteilen aus holz mit vollgewindeschrauben. KIT Scientific Publishing.).
In RFEM and RSTAB, you can design members with the "Laminated Veneer Lumber" material type. The following manufacturers are available:
- Pollmeier (Baubuche)
- Metsä (Kerto LVL)
- STEICO
- Stora Enso
In the ultimate configuration, you can consider strength coefficients for increasing the strengths. The coefficients reducing the strengths are automatically taken into account regardless of this. Try it now!
Go to Explanatory VideoThe design of cold-formed steel members according to the AISI S100-16 / CSA S136-16 is available in RFEM 6. Design can be accessed by selecting “AISC 360” or “CSA S16” as the standard in the Steel Design Add-on. “AISI S100” or “CSA S136” is then automatically selected for the cold-formed design.
RFEM applies the Direct Strength Method (DSM) to calculate the elastic buckling load of the member. The Direct Strength Method offers two types of solutions, numerical (Finite Strip Method) and analytical (Specification). The FSM signature curve and buckling shapes can be viewed under Sections.
In the Timber Design add-on for RFEM, you can design members as well as surfaces according to Eurocode 5, SIA 265 (Swiss standard), CSA O86 (Canadian standard), or ANSI/AWC NDS (American standard); for example, cross-laminated timber, glued-laminated timber, softwood, mass timber, and so on.
Go to Explanatory Video- A wide range of cross-sections, such as rectangular sections, square sections, T‑sections, circular sections, built-up cross-sections, irregular parametric cross-sections, and many others (suitability for design depends on the selected standard)
- Design of cross-laminated timber (CLT)
- Design of timber-based materials and laminated veneer lumber according to EC 5
- Design of tapered and curved members (design method according to the standard)
- Adjustment of the essential design factors and standard parameters is possible
- Flexibility due to detailed setting options for basis and extent of calculations
- Fast and clear results output for an immediate overview of the result distribution after the design
- Detailed output of the design results and essential formulas (comprehensible and verifiable result path)
- Numerical results clearly arranged in tables and graphical display of the results in the model
- Integration of the output into the RFEM/RSTAB printout report
- Design of tension, compression, bending, shear, torsion, and combined internal forces
- Consideration of a notch
- Design of compression perpendicular to the grain on the end and intermediate supports with (EC 5) and without reinforcement elements (fully threaded screws)
- Optional shear force reduction at the support (see the Product Feature)
- Design of curved and tapered members
- Consideration of higher strengths for similar components that are close together (factor ksys according to EN 1995‑1‑1, 6.6(1)-(3))
- Option to increase shear resistance for softwood timber according to DIN EN 1995‑1‑1:NA NDP to 6.1.7(2)
- 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)
- Arbitrary definition of the charring time
- Option to calculate with or without adhesion of the layer for surface structures (cross-laminated timber)
- Free user-defined specification of the fire parameters
- Consideration of Different Effective Lengths in Fire Resistance Design
- Optional design "Compression perpendicular to grain"
- Graphical result display integrated in RFEM/RSTAB, such as a design ratio
- Complete integration of the results into the RFEM/RSTAB printout report
RFEM/RSTAB also provides a range of functions for the case of a fire. The program allows for the automatic generation of load and result combinations for the accidental design situation of fire design. The members to be designed with the corresponding internal forces are imported directly from RFEM/RSTAB. Also, all information about the material and cross-section is stored. You don't need to do anything else.
You only define the parameters relevant for the fire resistance design by assigning a fire resistance configuration to the members and surfaces to be designed. Moreover, you can also make further detailed settings, such as the definition of the fire exposure on one side up to all sides.
As you probably know, the design checks for the selected members are carried out, taking into account the defined charring time. All necessary reduction factors and coefficients are stored accordingly in the program and are taken into account when determining the load-bearing capacity. That saves you a lot of work.
The effective lengths for the equivalent member design are taken directly from the strength entries. You do not have to enter them again.
After completing the design, the program presents the fire resistance design checks clearly and with all result details. This allows you to follow the results completely transparently. The results also contain all the required parameters, so you can determine the component temperature at the design time.
In addition to all these features, the program allows you to integrate all result tables and graphics, including the ultimate and serviceability limit state results,into the global printout report of RFEM/RSTAB as a part of the steel design results.
For the design according to Eurocode 5, the parameters of the National Annexes (NA) are integrated for the following countries:
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DIN EN 1995-1-1/NA:2014-07 (Germany)
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ÖNORM EN 1995-1-1/NA:2019-06 (Austria)
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SN EN 1995-1-1/NA:2015-03 (Switzerland)
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BDS EN 1995-1-1/NA:20157-06 (Bulgaria)
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BS EN 1995-1-1/NA:2019-09 (United Kingdom)
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CEN EN 1995-1-1/2014-05 (European Union)
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CYS EN 1995-1-1/NA:2019-06 (Cyprus)
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CZE EN 1995-1-1/NA:2015-05 (Czech Republic)
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DS EN 1995-1-1/NA:2019-09 (Denmark)
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ELOT EN 1995-1-1/NA:2010-01 (Greece)
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EVS EN 1995-1-1/NA:2015-11 (Estonia)
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HRN EN 1995-1-1/NA:2015-03 (Croatia)
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I S. EN 1995-1-1/NA:2014-05 (Ireland)
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ILNAS EN 1995-1-1/NA:2020-3 (Luxembourg)
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IST EN 1995-1-1/NA:2014-09 (Iceland)
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LST EN 1995-1-1/NA:2014-06 (Lithuania)
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LVS EN 1995-1-1/NA:2014-12 (Latvia)
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MSZ EN 1995-1-1/NA:2015-06 (Hungary)
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NBN EN 1995-1-1/NA:2014-06 (Belgium)
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NEN EN 1995-1-1/NA:2014-06 (Netherlands)
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NF EN 1995-1-1/NA:2020-04 (France)
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NP EN 1995-1-1/NA:2014-09 (Portugal)
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NS EN 1995-1-1/NA:2014-08 (Norway)
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PN EN 1995-1-1/NA:2014-07 (Poland)
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SFS EN 1995-1-1/NA:2016-12 (Finland)
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SIST EN 1995-1-1/NA:2018-01 (Slovenia)
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SR EN 1995-1-1/NA:2014-12 (Romania)
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SS EN 1995-1-1/NA:2018-02 (Singapore)
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SS EN 1995-1-1/NA:2014-05 (Sweden)
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STN EN 1995-1-1/NA:2019-12 (Slovakia)
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TKP EN 1995-1-1/NA:2019-09 (Belarus)
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UNE EN 1995-1-1/NA:2016-04 (Spain)
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UNI EN 1995-1-1/NA:2016-11 (Italy)
Your options in timber design are diverse. You can consider cut-to-grain angles, transverse tension stresses, and volume-dependent radii of curvature for tapered and curved members. To design the area of the grain cut, the strength is adjusted accordingly in the case of bending tension or bending pressure. In order to also allow you to perform a stability analysis with the equivalent member method, the height to determine the effective and lateral-torsional buckling lengths is set at a distance of 0.65 × h to the actual design point.
Here you have a free choice. You can perform the support pressure design at any point for the loading in the y- and z-directions of a cross-section. You are free to differentiate between inner and outer supports. A factor kc,90 for the pressure perpendicular to the grain can be user-defined (for example, 1.75 for glued-laminated timber). If allowed, the support length is increased automatically according to the standard specifications. This allows you to achieve a more efficient design with minimum effort.
There is often no fire resistance design for the lateral supports of a structure. Would you like to handle this differently in your project? In order to consider this in the calculation, you can define other equivalent member lengths for the fire situation.
What happens when there is a downwind? The topside lateral-torsional bracing is not applied to reduce the effective lengths and lateral-torsional buckling lengths.
Dlubal Software just makes everything a little easier. The performed design checks of the design standard are displayed in a clear way. A design criterion is determined for each design check. Furthermore, the program deliver the design details displayed in a structured way, including the initial values, the intermediate results, and the final results. An information window in the design details shows you the calculation process with the applied formulas, standard sources, and results in great detail.
Are you still looking for the design? The design checks are available in tabular form in the Timber Design add-on. Moreover, the program can also show you the distribution of the design ratios graphically. Extensive filter options are available for you in the table as well as in the graphical output, and you can use them to display the desired design checks by limit state or design type.
Did you know? You can individually define the reference lengths to be considered in the calculation of the deflection limit value and the segments to be checked, depending on the direction. For this, define design supports at the intermediate nodes of a member and assign them to the respective direction for the deformation analysis. In the resulting segments, you can also define a precamber for each direction and segment.
Use the member cross-section reductions to consider the start, internal, or end notches of a beam. The beam reduction is thus taken into account in the calculation of the load-bearing capacity. However, this does not apply to the stiffness.
Did you use the eigenvalue solver of the add-on to determine the critical load factor within the stability analysis? If so, you can then display the governing mode shape of the object to be designed as a result. The eigenvalue solver is available here for the lateral-torsional buckling analysis, depending on the design standard used.
You can enter the structural system and calculate the internal forces in the programs RFEM and RSTAB. You have full access to the extensive material and cross-section libraries.
Timber Design is completely integrated into the main programs. At the same time, it automatically takes into account the structure and the available calculation results. You can assign further entries for the timber design, such as effective lengths, cross-section reductions, or design parameters, to the objects to be designed. You can easily select the elements graphically using the [Select] function at many places of the program.
If your design is successful, the relaxed part of your work follows. Because the program does many processes for you. For example, the performed design checks are displayed in a table. It shows you all the result details. Due to the clearly presented design formulas, you will be able to understand the results without any problems. There is no "black box" effect here.
The design checks are carried out at all governing locations of the members and displayed graphically as a result diagram. Furthermore, detailed graphics, such as the stress distribution on a cross-section or the governing mode shape, are available for you in the result output.
All input and result data are part of the RFEM/RSTAB printout report. You can select the report contents and extent specifically for the individual design checks.
- Calculation of deflections and comparison with the normative or manually adjusted limit values
- Consideration of a precamber for the deflection analysis
- Different limit values are possible, depending on the design situation type
- Manual adjustment of reference lengths and segmentation by direction
- Calculation of deflections related to the initial structure or to the deformed structure
- Automatic consideration of time-dependent deformations by increasing the load with the creep factor (can also be user-defined on the stiffness side)
- Simplified vibration design
- Graphical result display integrated in RFEM/RSTAB; for example, the design ratio of a limit value, the deformation, or the sag
- Complete integration of the results into the RFEM/RSTAB printout report
Your RFEM/RSTAB program is responsible for generating and calculating the load and result combinations required for the serviceability limit state. Select the design situations for the deflection analysis in the Timber Design add-on. The calculated deformation values are then determined at each location of a member, depending on the specified precamber and the reference system, and then compared to the limit values.
You can specify the deformation limit value individually for each structural component in Serviceability Configuration. In this case, the maximum deformation should not exceed the permissible limit value, depending on the reference length. When defining design supports, you can segment the components. This allows you to determine the corresponding reference length automatically for each design direction.
Based on the position of the assigned design supports, the program automatically determines the difference between beams and cantilevers. Thus, you can be sure that the limit value is determined accordingly.
You find the serviceability limit state design fully integrated in the result tables of the Timber Design add-on. If yuo want to check the design results, you can open the program and display the results with all the details at each location of the designed members. Furthermore, graphics are available for you with the result diagrams of the design ratios.
A special thing is that All result tables and graphics can be integrated into the global printout report of RFEM/RSTAB as a part of the timber design results. You can also display and document the deformations of the entire structure as a part of the RFEM/RSTAB functionality. This function is independent of the add-on.
In the RF-LAMINATE add-on module for RFEM, the design of torsional shear stresses in the superposition of net and gross cross-section values is possible. The design is performed separately in the x- and y-directions. The loads on the intersection points of cross-laminated timber panels are checked.
At first, the governing joint designs are arranged in groups and displayed with the basic geometry of the joint in the first result window. In the other result windows, you can see all fundamental design details.
Dimensions, material properties, and welds important for the connection construction are displayed immediately and can be printed directly. Similarly, export to DXF-file is enabled. The connections can be visualized in the RF-/JOINTS Timber - Timber to Timber module as well as in RFEM/RSTAB.
All graphics can be included in the RFEM/RSTAB printout report or printed directly. Due to the scaled output, an optimal visual check is possible as early as in the design phase.
The following design results are displayed:
- Check of minimum spacing
- Load-carrying capacity of each screw
First, select the joint type and the design standard.
The connected members are imported from the RFEM/RSTAB model. The add-on module automatically checks if all geometry conditions are fulfilled.
In addition, the loads are imported automatically from RFEM/RSTAB. In the Geometry window, you can specify the screw parameters (diameter, length, angle, and so on).