Using Modified Stiffnesses for Dynamic Calculations

  • Knowledge Base

Tips & Tricks

This article was translated by Google Translator

View original text

In RFEM, it is possible to modify stiffnesses for materials, cross -sections, members, load cases, and load combinations in many places. In order to consider these modifications when determining the natural frequencies, there are two options in RF-DYNAM Pro.

In the present example, the stiffness of the reinforced concrete columns is to be reduced in order to simulate state II.

The reduction with the factor 0.6 is carried out at the level of the "Rectangle 300/300" cross -section.

In order to consider these modifications of the cross -section when determining the natural frequencies, you have to select the second option under the calculation parameters under "Stiffness changes".

Due to the reduced stiffness, there is thus a lower natural frequency for the first mode shape.

Author

Dipl.-Ing. (FH) Frank Sonntag, M.Sc.

Dipl.-Ing. (FH) Frank Sonntag, M.Sc.

Sales & Customer Support

Mr. Sonntag coordinates the Dlubal Software office in Leipzig and is responsible for sales and customer support.

Keywords

Stiffness Modify stiffness Natural frequency

Links

Write Comment...

Write Comment...

  • Views 255x
  • Updated 04/07/2021

Contact us

Contact Dlubal

Do you have questions or need advice?
Contact 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

Online Training | English

RFEM for Students | USA

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

Online Training | English

RFEM | Basics

Online Training 04/23/2021 8:30 AM - 12:30 PM CEST

Online Training | English

RFEM | Timber | USA

Online Training 05/05/2021 1:00 PM - 4:00 PM CDT

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 CEST

Timber structures | Part 2: design

Timber Beam and Surface Structures | Part 2: Design

Webinar 05/11/2021 2:00 PM - 2:45 PM CEST

Online Training | English

Eurocode 2 | Concrete structures according to DIN EN 1992-1-1

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

Online training | English

RFEM for Students | Part 2

Online Training 05/17/2021 2:00 PM - 4:30 PM CEST

Online Training | English

Eurocode 5 | Timber structures according to DIN EN 1995-1-1

Online Training 05/20/2021 8:30 AM - 12:30 PM CEST

Online training | Arabic

RFEM | Basics | Arabic

Online Training 05/20/2021 8:30 AM - 12:30 PM CEST

Online Training | English

RFEM | Structural dynamics and earthquake design according to EC 8

Online Training 06/02/2021 8:30 AM - 12:30 PM CEST

Online training | English

RFEM for Students | Part 3

Online Training 06/15/2021 2:00 PM - 4:30 PM CEST

Online Training | English

RFEM | Basics | USA

Online Training 06/17/2021 9:00 AM - 1:00 PM CDT

Plate and Shell Buckling Utilizing Dlubal Software

Plate and Shell Buckling Utilizing Dlubal Software

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

CSA S16:19 Steel Design in RFEM

CSA S16:19 Steel Design in RFEM

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

The Most Common User Errors With RFEM and RSTAB

The Most Common User Errors With RFEM and RSTAB

Webinar 02/04/2021 2:00 PM - 3:00 PM CET

ADM 2020 Member Design in RFEM

ADM 2020 Member Design in RFEM

Webinar 01/19/2021 2:00 PM - 3:00 PM CDT

Dlubal Info Day

Dlubal Info Day Online | December 15, 2020

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

FEA Troubleshooting and Optimization in RFEM

FEA Troubleshooting and Optimization in RFEM

Webinar 11/11/2020 2:00 PM - 3:00 PM CDT

Soil-Structure Interaction in RFEM

Soil-Structure Interaction in RFEM

Webinar 10/27/2020 2:00 PM - 2:45 PM CET

NBC 2015 Modal Response Spectrum Analysis in RFEM

NBC 2015 Modal Response Spectrum Analysis in RFEM

Webinar 09/30/2020 2:00 PM - 3:00 PM CDT

Documenting Results in the RFEM Printout Report

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

ACI 318-19 Concrete Design in RFEM

ACI 318-19 Concrete Design in RFEM

Webinar 08/20/2020 2:00 PM - 3:00 PM CDT

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
RFEM Dynamic Analysis
RF-DYNAM Pro - Natural Vibrations  5.xx

Add-on Module

Dynamic analysis of natural frequencies and mode shapes of member, surface, and solid models

Price of First License
1,030.00 USD