In spite of the hinge, I obtain a bending moment My for the rib member. Why?


Member internal forces (for example, the bending moment My) of a rib member are not only dependent on the defined member hinges, but also on the surface internal forces in the slab. 

When entering a rib, specify the integration width of the surface internal forces.

The rib internal forces consist of the member internal forces of the eccentrically connected rectangular cross-section and the surface internal forces integrated by the integration width.

It means that you can obtain the bending moment My for a rib member in spite of entering member hinges, because the bending moment can originate from the integrated surface internal forces.

In the Display navigator, you can specify whether to display the results including the contribution of the surface internal forces (default setting).

Or without the contribution of the surface internal forces.

In order to obtain a "zero crossing" of the moment My in the rib member, it would be necessary to insert a line hinge in the area of the connection of the plate to the wall.


Rib Hinge Moment T-beam Internal forces Downstand beam



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

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

Price of First License
3,540.00 USD