Defining a spectrum using values of S as a function of frequency and damping
Required parameters
- NAME
Set this parameter equal to a label that will be used to refer to the spectrum. This label is used to cross-reference a spectrum on the RESPONSE SPECTRUM option.
Optional parameters
- G
Set this parameter equal to the value of the acceleration of gravity. This parameter is used only when TYPE=G is specified.
- INPUT
Set this parameter equal to the name of the alternate input file containing the data lines for this option. See Input Syntax Rules for the syntax of such file names. If this parameter is omitted, it is assumed that the data follow the keyword line.
- TYPE
Set TYPE=DISPLACEMENT, TYPE=VELOCITY, or TYPE=ACCELERATION (default) to define the units in which the spectrum is defined.
Set TYPE=G to enter an acceleration spectrum in g-units. The parameter G then defines the gravitational acceleration.
Date lines to define a spectrum using values of S as a function of frequency and damping
- First line
Magnitude of the spectrum.
Frequency, in cycles per time, at which this magnitude is used.
Associated damping, given as ratio of critical damping.
Repeat this data line as often as necessary to define the spectrum at all frequencies at each damping value.