Modal Analysis

Glossary Term

A modal analysis allows for the dynamic analysis of structural systems capable of vibrating. As a result, natural vibration values are determined, such as natural frequency, a mode shape, modal mass, and effective modal mass factors.

The modal analysis is the basis for further dynamic analysis, such as for loading by a response spectrum or a time diagram. This is a completely linear method; the nonlinearities existing in the system are not taken into account.

Modal Analysis in RF-/DYNAM Pro

It is possible to perform the modal analysis in RFEM or RSTAB by using the RF-/DYNAM Pro add-on module. In addition to the results of modal parameters in tables, the natural vibration modes are also available graphically for the evaluation.

Furthermore, the modal analysis represents a method for solving time history. In this case, the determined eigenvalues and mode shapes of the model are directly used.

Keywords

Eigenvalue analysis Eigenvalue problem Dynamics Natural vibration Natural frequency Mode shape Modal mass Modal mass factor

Bibliography

Links

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
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
RSTAB Dynamic Analysis
DYNAM Pro - Natural Vibrations 8.xx

Add-on Module

Dynamic analysis of natural frequencies and mode shapes of member models

Price of First License
850.00 USD
RSTAB Dynamic Analysis
DYNAM Pro - Forced Vibrations 8.xx

Add-on Module

Dynamic and seismic analysis including time history analysis and multi-modal response spectrum analysis

Price of First License
1,120.00 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
RFEM Dynamic Analysis
RF-DYNAM Pro - Forced Vibrations 5.xx

Add-on Module

Dynamic and seismic analysis including time history analysis and multi-modal response spectrum analysis

Price of First License
1,120.00 USD