The calculation of a critical load factor according to the second-order analysis in RSTAB results in a value that differs significantly from the result of RSBUCK.


Check if the settings for considering the favorable effect by tension forces are the same in RSTAB and RSBUCK.

RSTAB determines the critical load factor according to the nonlinear calculation method: The loading is increased gradually by the value of the load factor increment Δk until the system becomes unstable. On the other hand, RSBUCK performs a linear eigenvalue analysis. Therefore, the elements acting nonlinearly, such as failing members or supports, may have different effects in RSTAB and RSBUCK.


Critical factor Load factor Eigenvalue analysis Critical load factor Load increment

Contact us

Did you find your question?
If not, contact us via our free e-mail, chat, or forum support, or send us your question via the online form.

+49 9673 9203 0


Add-on Module

Stability analysis according to the eigenvalue method

Price of First License
670.00 USD
RSTAB Main Program
RSTAB 8.xx

Main Program

The structural engineering software for design of frame, beam and truss structures, performing linear and nonlinear calculations of internal forces, deformations, and support reactions

Price of First License
2,550.00 USD