The RSX program is used to calculate the cutting forces and support forces for general bar-shaped load-bearing structures as 2-d or, optionally, 3-d systems. The graphical input with templates and wizards quickly provides a calculable system. The initial values for a design for steel, timber, reinforced concrete or aluminum are provided with the fully automatic superposition. Eigenvalues and eigenmodes can be calculated for dynamic investigations. The scope of performance depends on the purchased add-ons.

to the shop

Discover more products from the FRILO portfolio now!

  • Steel
  • Timber
  • Reinforced concrete
  • Aluminum
  • User-defined material
  • The system can be entered either interactively via the graphical user interface and/or by entering the data in tables
  • Marking of several objects for joint editing
  • Undo/Redo to undo or restore any user action
  • All kinds of concentrated loads, line loads, and trapezoidal loads
  • Area loads on panels (areas limited by members)
  • Load action as a force and/or as a mass
Structuring options
  • Subsystems to group any members
  • Set of members to create line-type components across several members
  • Standard steel shapes from the cross-section library
  • General steel sections from the Q3 program
  • User-defined cross-sections via structural values or geometric data
  • Elastic and plastic design
  • Stability calculation on the individual member or on a set of members
  • Transfer of members and sets of members with all loads and internal forces to the BTII+ program for stability calculations
  • General stress analysis
  • Equivalent member verification with specification of the effective lengths for buckling and lateral buckling
Reinforced Concrete
  • Reinforced concrete design with multiple options for the arrangement of the reinforcement
  • Kd method for plane components, optimised for flexural reinforcement
  • Reinforcement distributed over corners for biaxial bending for spatial systems
  • Design for shear force and torsion, also for biaxial shear force
  • Stress analysis
  • Transfer of members and sets of members with all loads and internal forces to the BTII+ program for stability analysis
Text output
  • Detailed control of the output of all results for load cases, superposition and design situations via a general output profile
Graphic output
  • Free selection of all kinds of images
  • All results can be represented graphically
  • Result filter adjustable via minimum and maximum values
  • Images are generated via the Snapshot function in accordance with the WYSIWYG principle
  • Images are automatically grouped by content
  • Image management for inserting or hiding images in the document
Document structure
  • All chapters of the document can be hidden/displayed directly in the document
  • Customisation of the document without need to re-create it afterwards
  • Automatic adjustment of the result graphics in the document
  • The structure and the layout of the document can be adjusted via the general FRILO layout.
Transfer options


  • Lateral Torsional Buckling Analysis BTII
  • Isolated Foundation FD+
  • Fin Plate SFB+
  • Steel Frame Corner SRE+
  • Reinforced Concrete Column B5+



  • Timber Truss FWH+
  • Steel Truss FWS+
  • All roof programs of DACH+
  • Continuous Timber Beam HTM+
  • Continuous Steel Beam STM+
Import options
  • From DXF to transfer geometric data.
  • From Excel to transfer nodes and members.
  • Planned for coming versions: data transfer from FRILO BIM Connector®.
Export options
  • Result data to Excel for further processing. Maximum values at each member and maximum values at each node.
  • Word
3-d add-on RSX-3D
  • The basic module is conceived for the calculation of plane frames.
  • This add-on enhances the modelling to 3-d systems.
Materials, design add-ons RSX-M-S/RSX-M-H/RSX-M-B
  • RSX can be used without defining materials. The basic licence includes the 2-d calculation of internal forces and support reactions as well as the automatic superposition.
  • Optionally, design modules for steel (includes aluminum), timber and reinforced concrete structures are available.
Load entry with Panels with add-on RSX-P
  • Freely definable areas for the definition of area loads
  • Free assignment of members for the load transfer
  • Distribution of the area loads on the members via an FE analysis
Stability steel add-on RSX-ST
  • Verification of the stability of individual members and sets of members
  • The calculation is based on the verifications performed in the BTII+ program
  • The licence is automatically available when the BTII+ program is installed
Dynamics add-on RSX-DY
  • Calculation of resonance frequency and mode shapes for load cases and user-defined superpositions
Structural calculation
  • First-order analysis
  • Second-order analysis
  • Possible failure of members or foundations
  • Dynamic analysis of load cases and user-defined superpositions
  • Calculation of eigenvalues and mode shapes
Buckling load
  • Solution of the static eigenvalue problem to determine the ideal limit loads for the stability of the system
  • Calculation of eigenvalues and mode shapes
  • Automatic superposition of the load cases
  • Grouping of load cases for concurrent or alternative action

Support resources