FAQ 002110 EN

Results RFEM RSTAB 5.xx 8.xx

How RFEM and RSTAB calculate the moment of inertia ly of a castellated beam from the library?

Answer

RFEM and RSTAB calculate a reduced moment of inertia ly according to the article "Design of Castellated Beams" by Rolf Kindmann, H. J. Nieburh, H. Schweppe.

The reduced moment of inertia ly, for example for WAB HEB 340‑340, is calculated as follows:

red ly = 0.8 * A * ((H - tg) / 2)2

red ly = 0.8 * 150.50 * ((51.00 - 2.15) / 2)2 = 71.828 cm4
RFEM Main Program
RFEM 5.xx

Main Program

Structural engineering software for finite element analysis (FEA) of planar and spatial structural systems consisting of plates, walls, shells, members (beams), solids and contact elements

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