Knowledge Base

Useful Program Features

Dlubal Software programs and add-on modules include a wide range of powerful features. In addition to product features, you can find here technical articles and application examples.

Furthermore, this overview provides you with several handy tips and tricks for your work with RFEM and RSTAB.

Search

Fulltext

Type

Why Dlubal Software?

Solutions

More than 25,000 users in 71 countries
One software package for all application areas
Short learning time and intuitive handling
Service provided by experienced engineers
Excellent price/performance ratio
Flexible modular concept, extensible according to your needs
Scalable license system with single and network licenses
Proven software used in many well-known projects

New 001456 Technical Article Timber Structures RFEM Modeling | Structure

Bending Beam with Circular Opening

This article presents a bending beam with a circular opening analyzed using the numerical method. As a reference point, there is an example of a perforated beam from [1]. In our case, the 3D model was simplified to a two-dimensional discretization.
New 001455 Technical Article Building Information Modeling (BIM) RFEM RSTAB Import / Export & BIM

Revit Interface: Export

BIM is often used when it comes to data management in civil engineering. The individual disciplines of architecture, structural design, construction, and structural monitoring are coming closer together. Building Information Modeling makes this possible.
Dlubal Software provides a wide range of formats for data exchange. The following article explains the details of the interface with Autodesk Revit and, particularly the export settings.
New 001454 Technical Article Steel Structures Stability Analysis RFEM RF-/PLATE-BUCKLING RF-STABILITY Design Eurocode 3

Calculating Critical Load Factor for Linear Buckling Analysis

Buckling analysis according to the effective width method or the reduced stress method is based on the determination of the system critical load, hereinafter called LBA (linear buckling analysis). This article explains the analytical calculation of the critical load factor as well as utilisation of the finite element method (FEM).
New 001452 Technical Article Concrete Structures RF-CONCRETE CONCRETE Add-on Modules Eurocode 2

Downstand Beams, Ribs, T-Beams: Shear Joints

In the construction process, it is often necessary to fabricate the concrete elements in sections. A classic example of this production in sections is the use of prefabricated downstand beams, in which the slab is completed in the on-site concrete construction. By creating a new concrete area, interfaces may arise between the already hardened concrete and the fresh concrete. The transfer of the longitudinal shear forces arising between the partial cross-sections must be considered in the design.
New 001348 Product Description Nonlinear Dynamics RF-/DYNAM Pro - Nonlinear Time History General Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Features
- User-defined time diagrams as a function of time, in a tabular form, or as harmonic loads
- Combination of the time diagrams with RFEM/RSTAB load cases or combinations (enables definition of nodal, member and surface loads as well as free and generated loads varying over time)
- Combination of several independent excitation functions
- Nonlinear time history analysis with the implicit Newmark analysis (RFEM only) or the explicit analysis
- Structural damping using Raleigh damping coefficients or Lehr's damping
- Direct import of initial deformations from a load case or combination (RFEM only)
- Stiffness modifications as initial conditions, for example axial force effect, deactivated members (RSTAB only)
- Graphical display of results in a time course monitor
- Export of results in user-defined time steps or as an envelope
New 001349 Product Description Nonlinear Dynamics RF-/DYNAM Pro - Nonlinear Time History General Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Nonlinearities
- Nonlinear member types, such as tension and compression members or cables
- Member nonlinearities, such as failure, tearing, yielding under tension or compression
- Support nonlinearities, such as failure, friction, diagram (RSTAB only, RFEM - beta), and partial activity
- Release nonlinearities, such as friction, partial activity, diagram, and fixed if positive or negative internal forces (RSTAB only, RFEM - beta)
New 001350 Product Description Nonlinear Dynamics RF-/DYNAM Pro - Nonlinear Time History General Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Beta Version Limits
- Time history analysis of acceleration-time excitations on supports currently in development
- Printout report in work
- Further improvements of linear and nonlinear hinges and releases (RFEM only)
- Nonlinear material models (RFEM only) in development
- Contact elements (RFEM only) currently not supported
- Option to import the initial state from a load case or load combination (RFEM only) in preparation
New 001351 Product Description Nonlinear Dynamics RF-/DYNAM Pro - Nonlinear Time History Add-on Modules Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Input

RF-/DYNAM Pro - Nonlinear Time History is integrated in the structure of RF‑/DYNAM Pro - Forced Vibrations and extended by two nonlinear analysis methods (one nonlinear analysis in RSTAB).

Force-time diagrams can be entered as transient, periodic or as a function of time. Dynamic load cases combine the time diagrams with the static load cases, which provides a great flexibility. Furthermore, it is possible to define time steps for the calculation, structural damping, and export options in the dynamic load cases.
New 001352 Product Description Dynamic and Seismic Analysis RF-/DYNAM Pro - Nonlinear Time History Calculation Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Calculation

Calculation in RFEM
The nonlinear time history analysis is performed with the implicit Newmark analysis or the explicit analysis. Both are the direct time integration methods. The implicit analysis requires small time steps to provide precise results. The explicit analysis determines the required time step automatically to provide the stability to the solution. The explicit analysis is suitable for the analysis of short excitations, such as impulse excitation, or an explosion.

Calculation in RSTAB
The nonlinear time history analysis is performed with the explicit analysis. This is a direct time integration method and determines the required time step automatically in order to provide the solution stability.
New 001353 Product Description Dynamic and Seismic Analysis RF-/DYNAM Pro - Nonlinear Time History Calculation Eurocode 8

RF-/DYNAM Pro - Nonlinear Time History | Results

Due to the integration of RF‑/DYNAM Pro in RFEM or RSTAB, you can incorporate numeric and graphic results from RF‑/DYNAM Pro - Forced Vibrations to the global printout report. Also, all RFEM and RSTAB options are available for a graphical visualization. The results of the time history analysis are displayed in a time course monitor.

All results are plotted versus time. You can export the numeric values to MS Excel. It is possible to export the result combinations by exporting the results of the individual time steps or filtering the most unfavourable results of all time steps.