In RFEM and RSTAB, you can visualize the flow field quantities of pressure, velocity, turbulence kinetic energy, and turbulence dissipation rate for the wind simulation.
The clipping planes are aligned with the respective wind direction.
In the Geotechnical Analysis add-on, the Hoek-Brown material model is available. The model shows linear-elastic ideal-plastic material behavior. Its nonlinear strength criterion is the most common failure criterion for stone and rocks.
You can enter the material parameters using
Rock parameters directly, or alternatively via
GSI classification.
Detailed information about this material model and the definition of the input in RFEM can be found in the respective chapter Hoek-Brown Model of the online manual for the Geotechnical Analysis add-on.
For calculation diagrams, the "2D | Hinge" is available. These hinge diagrams show the hinge response of load situations for nonlinear hinges.
For calculations with several load situations, such as is the case with pushover analyzes and time history analysis, you can evaluate the state of the hinge in each load step.
If you have experimentally determined surface pressures available for a model, you can apply them to a structural model in RFEM 6, process them in RWIND 2, and use them as wind loads in the structural analysis of RFEM 6.
You can find out how to apply the experimentally determined values in this technical article.
The Time History Analysis add-on provides you with accelerograms for the calculation. This extension allows for dynamic structural analysis of the acceleration-time diagrams.
There is an extensive library of earthquake records available for you, but you can also enter or import your own diagrams. The time history analysis is performed using the modal analysis or the linear implicit Newmark analysis.
The modal relevance factor (MRF) can help you to assess to which extent specific elements participate in a specific mode shape. The calculation is based on the relative elastic deformation energy of each individual member.
The MRF can be used to distinguish between local and global mode shapes. If multiple individual members show significant MRF (for example, > 20%), the instability of the entire structure or a substructure is very likely. On the other hand, if the sum of all MRFs for an eigenmode is around 100%, a local stability phenomenon (for example, buckling of a single bar) can be expected.
Furthermore, the MRF can be used to determine critical loads and equivalent buckling lengths of certain members (for example, for stability design). Mode shapes for which a specific member has small MRF values (for example, < 20%) can be neglected in this context.
The MRF is displayed by mode shape in the result table under Stability Analysis → Results by Members → Effective Lengths and Critical Loads.
The combination wizard provides you with the option to consider more than one initial state. RFEM and RSTAB allow you to specify different initial states (prestress, form-finding, strain, and so on) for the target combinations in the combinatorics.
You can thus, for example, generate load states on the basis of a form-finding analysis with varying imperfections.
In RFEM 6 and RSTAB 9, you can export line graphics to the SVG format (vector graphics).
SVG stands for Scalable Vector Graphics and is an XML-based file format for displaying two-dimensional vector graphics. These vector graphics can be scaled without loss. It is possible to edit the SVG files using text editors, embed them on websites, and open them in the usual browsers.
Within the "Plastic capacity design | Simplex Method" in RSECTION, the simultaneous variation of shear stresses over the cross-sectional area is performed in addition to the variation of axial stresses. This extended form of analysis allows you to use redistribution reserves, especially for the cross-sections subjected to shear loading, thus loading the cross-sections even more efficiently.
The "Spring" member type is used to simulate linear and nonlinear spring properties via a linear object. This input function helps you to model the stiffness specifications in the force/displacement unit.
It is necessary to enter the required force-time diagrams. They can be combined in load cases or load combinations of the type Time History Analysis | Time Diagrams with the loading in order to define where and in which direction the force-time diagrams act.
The second option is to enter acceleration-time diagrams, which can be used in the load cases of the Time History Analysis | Accelerogram type.
All calculation parameters are specified in the time history analysis settings. These include, for example, the type of analysis method and the maximum calculation time.
The time history analysis is performed with the modal analysis or the linear implicit Newmark analysis. The time history analysis in this add-on is limited to linear structural systems. Although the modal analysis represents a fast algorithm, it is necessary to use a certain number of eigenvalues to ensure the required accuracy of results.
The implicit Newmark analysis is a very precise method, independent of the number of eigenvalues used, but requires sufficient small time steps for the calculation.
The model and loads are entered as usual in the RFEM interface.
You can start the cloud calculation by selecting an entry in the Calculate menu. Then, select the virtual machine suitable for the task and start the calculation.
After the start, the image is used to create a virtual machine on which the computing server is started. This takes over the calculation of your file.
You can monitor the processing of calculation tasks in the Extranet.
After completing the calculation, you will receive an email with a link to download the calculated file. Large files are compressed into a ZIP archive. Smaller files can be downloaded directly.
As an alternative, there is a link to the calculated file in the Extranet.
The downloaded file is a common RFEM file and can be used for further processing as usual.
With the Concrete Design add-on, you can perform the fatigue design of members and surfaces according to EN 1992‑1‑1, Chapter 6.8.
For the fatigue design, you can optionally select two methods or design levels in the design configurations:
Design Level 1: Simplified design according to 6.8.6 and 6.8.7(2): The simplified design is performed for frequent action combinations according to EN 1992‑1‑1, Chapter 6.8.6 (2), and EN 1990, Eq. (6.15b) with the traffic loads relevant in the serviceability state. A maximum stress range according to 6.8.6 is designed for the reinforcing steel. The concrete compressive stress is determined by means of the upper and lower allowable stress according to 6.8.7(2).
Design Level 2: Design of damage equivalent stress acc. to 6.8.5 and 6.8.7(1) (simplified fatigue design): The design using damage equivalent stress ranges is performed for the fatigue combination according to EN 1992‑1‑1, Chapter 6.8.3, Eq. (6.69) with the specifically defined cyclic action Qfat.
In the "Steel Joints" add-on, you can consider preloaded bolts in all components during the calculation. You can easily activate the preloading using the check box in the bolt parameters, and it has an impact on the stress-strain analysis as well as the stiffness analysis.
Preloaded bolts are special bolts used in steel structures to generate a high clamping force between the connected structural components. This clamping force causes friction between the structural components, which allows for the transfer of forces.
Functionality Preloaded bolts are tightened with a certain torque, causing them to stretch and generate a tensile force. This tensile force is transferred to the connected components and leads to a high clamping force. The clamping force prevents the connection from loosening and ensures safe force transmission.
Advantages
High load-bearing capacity: Preloaded bolts can transfer large forces.
Low deformation: They minimize the deformation of the connection.
Fatigue strength: They are resistant to fatigue.
Easy assembly: They are relatively easy to assemble and disassemble.
Analysis and Design The calculation of preloaded bolts is performed in RFEM using the FE analysis model generated by the "Steel Joints" add-on. It takes into account the clamping force, friction between structural components, shear strength of bolts, and load-bearing capacity of the structural components. The design is carried out according to DIN EN 1993‑1‑8 (Eurocode 3) or the US standard ANSI/AISC 360‑16. You can save the created analysis model, including the results, and use it as an independent RFEM model.
The Ponding load type allows you to simulate rain actions on multi-curved surfaces, taking into account the displacements according to the large deformation analysis.
This numerical rainfall process examines the assigned surface geometry and determines which rainfall portions drain away and which rainfall portions accumulate in puddles (water pockets) on the surface. The puddle size then results in a corresponding vertical load for the structural analysis.
For example, you can use this feature in the analysis of approximately horizontal membrane roof geometries subjected to rain loading.
Several modeling tools are available for elements in building models:
Vertical line
Column
Wall
Beam
Rectangular floor
Polygonal floor
Rectangular floor opening
Polygonal floor opening
This feature allows you to define the element on the ground plane (for example, with a background layer) with the associated multiple element creation in space.
The Concrete Design add-on allows you to design fiber-reinforced concrete components according to the guideline "DAfStb Steel Fiber-Reinforced Concrete".
You can use this option for the design according to EN 1992‑1‑1. The design according to the DAfStb guideline is carried out once the concrete of the "Fiber Concrete" type has been assigned to the reinforced structural component.
You can simulate the static friction effects between two supporting components along a line using the "Friction" nonlinearity in the Line Release Type.
The "Building Grid" guide object supports you in the design of your structure. It features intuitive grid coordinate input and grid line labeling.
You can quickly place grids in space and label them by specifying a graded coordinate code. The grid line end modification allows you to optimize the grid appearance. Furthermore, a preview helps you to define the building grid.
You can display the RWIND results directly in the main program. In the Navigator - Results, select the Wind Simulation Analysis result type from the list above.
Currently, the following results are available, which refer to the RWIND computational mesh:
You can import STEP files into RFEM 6. The data is directly converted into the native RFEM model data.
The STEP format represents a standard interface initiated by ISO (ISO 10303). In the geometry description, all shapes relevant for RFEM (line, surface, and solid models) can be integrated by the CAD data models.
Note: This format is not to be confused with DSTV interfaces, which also use the file extension *.stp.
Use the "Import Support Reactions" Load Wizard in RFEM 6 and RSTAB 9 to easily transfer reaction forces from other models. The wizard allows you to connect all or several nodal and line loads of different models with each other in a few steps.
The load transfer from load cases and load combinations can be carried out automatically or manually. It's necessary that the models are saved in the same Dlubal Center project.
The "Import Support Reactions" load wizard supports the concept of positional statics and allows you to digitally connect the individual positions.
Using the "Load Transfer Only" story type, you can consider slabs without stiffness effect in and out of the plane in the Building Model add-on. This element type collects the loads on the slab and transfers them to the supporting elements of a 3D model. Thus, you can simulate secondary components, such as grillage and similar load distribution elements, without any further effect in the 3D model.