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sdof_response

Compute Response of a Single Degree of Freedom Oscillator to a Given Acceleration Record

Minimum version: v2.6

Reference:

  1. https://doi.org/10.1016/S0267-7261(05)80015-6

Please note the following.

  1. Only applies to elastic system.
  2. Only trivial initial conditions are accounted for.

Syntax

The frequency of the oscillator is used. Its unit is Hertz (Hz).

Please note the natural frequency shall not be passed to the command. The natural frequency has a unit of radian per second (rad/s).

Form A

For accelerogram record stored in single column plain text file. The following syntax can be used.

Text Only
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sdof_response (1) (2) (3) (4)
# (1) string, file path of the accelerogram file
# (2) double, sampling interval
# (3) double, frequency of the system
# (4) double, damping ratio

The accelerogram stores discrete acceleration amplitudes in the first column of the file.

As the accelerogram only provides the amplitudes, the sampling interval must be provided as the (2) argument.

Form B

For accelerogram record stored in double column plain text file. The following syntax can be used.

Text Only
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response_spectrum (1) (2) (3)
# (1) string, file path of the accelerogram file
# (2) double, frequency of the system
# (3) double, damping ratio

The accelerogram stores the time and acceleration amplitudes in the first and second columns of the file.

The time series must be equally spaced.

Example

See this example.