FUNDAMENTALS OF DYNAMIC ANALYSIS
Normal modes:
Normal modes analysis is used to determine the basic dynamic characteristics of a structure.
The results indicate the frequencies and shapes in which a structure naturally tends to vibrate.
Although the results are not based on a specific loading, they can be used to predict the effects of applying various dynamic loads .
Frequency response:
The load is a sine wave for which the frequency, amplitude and phase are specified.
Frequency response analysis is limited to linear elastic structures.
Transient response:
This is the most general method of computing the response to time-varying loads. Loading is explicitly defined for every point in time.
Transient response can include non-linear effects.