FAQ 002844 | I used double members when entering members. Do I have to consider anything else or is it better to enter a member with double cross-section properties?

Easily learn how to work with the Dlubal Software programs

  • Dlubal Software | Videos

Video

First Steps with RFEM

First steps

We provide hints and tips to help you get started with the basic program RFEM.

Please accept Marketing Cookies to watch this video.

Question

I used double members when entering members. Do I have to consider anything else or is it better to enter a member with double cross-section properties?

Answer

To design multi-part components, you can use the composite cross-sections of the cross-section library. In this case, the cross-section values are calculated automatically from the individual cross-sections and then also considered in the add-on modules for design. The shear-resistant connection of lattice members is shown here by entering an equivalent plate thickness t *.

Figure 03 - Combined cross-section

If you have edited the cross-section properties of a cross-section or the stiffnesses of a member with the "Modify Stiffness" function, they are generally not used in the design modules. The modified stiffnesses are only used for the calculation of internal forces.

Figure 01 - Stiffness modification in the calculation of internal forces

Figure 02 - Single angle with modification of stiffness

The designs in RF-/STEEL EC3 also require the exact dimensions and the shape of the cross-section for the c/t design or the selection of the interaction equation, for example. The effect of the stiffness modification on these individual parameters is not unique for all cases and thus cannot be used in the add-on module.

Figure 04 - Design ratio in RF-/STEEL EC3

Keywords

Dlubal FAQ Modify stiffness Steel design Design Double members Frequently Asked Question FAQ about Dlubal Question and Answer about Dlubal

Links

Write Comment...

Write Comment...

  • Views 45x
  • Updated 02/11/2021

Contact us

Do you have any questions about our products or need advice on selecting the products needed for your projects?
Contact us via our free e-mail, chat, or forum support or find various suggested solutions and useful tips on our FAQ page.

(267) 702-2815

info-us@dlubal.com

CSA S16:19 Steel Design in RFEM

CSA S16:19 Steel Design in RFEM

Webinar 03/10/2021 2:00 PM - 3:00 PM EST

Online Training | English

Eurocode 3 | Steel structures according to DIN EN 1993-1-1

Online Training 03/18/2021 8:30 AM - 12:30 PM CET

Plate and Shell Buckling Utilizing Dlubal Software

Plate and Shell Buckling Utilizing Dlubal Software

Webinar 03/30/2021 2:00 PM - 2:45 PM

Online Training | English

RFEM for Students | USA

Online Training 04/21/2021 1:00 PM - 4:00 PM EST

Online Training | English

Eurocode 3 | Steel structures according to DIN EN 1993-1-1

Online Training 05/06/2021 8:30 AM - 12:30 PM

Dlubal Info Day

Dlubal Info Day Online | December 15, 2020

Webinar 12/15/2020 9:00 AM - 4:00 PM CET

Documenting Results in the RFEM Printout Report

Webinar 08/25/2020 2:00 PM - 2:45 PM

Programmable COM Interface for RFEM/RSTAB

Programmable COM Interface for RFEM/RSTAB

Webinar 05/12/2020 3:00 PM - 3:45 PM

Webinar: Nonlinear Time History Analysis in RFEM

Nonlinear Time History Analysis in RFEM

Webinar 05/08/2018 3:00 PM - 4:00 PM EST