ABAQUS Keywords Reference Manual  

*RESPONSE SPECTRUM
Calculate the response based on user-supplied response spectra.

This option is used to calculate estimates of peak values of displacements and stresses based on user-supplied response spectra (defined using the *SPECTRUM option) and on the natural modes of the system.

Product: ABAQUS/Standard  

Type: History data

Level: Step  

References:

Optional parameters:

COMP

Set COMP=ALGEBRAIC to sum the directional excitation components algebraically. If this parameter is used, the directional excitation components are summed first, followed by the modal summation.

Set COMP=SRSS (default) to use the square root of the sum of the squares. If this parameter is used, the modal summation is performed first, followed by the summation of the directional excitation components.

SUM

Set SUM=ABS (default) to sum the absolute values of the responses in each natural mode.

Set SUM=CQC to use the complete quadratic combination method to sum the responses in each natural mode.

Set SUM=NRL to use the Naval Research Laboratory method.

Set SUM=SRSS to use the square root of the sum of squares summation.

Set SUM=TENP to use the Ten Percent Method.

Data lines for a response spectrum analysis: 

First line:

  1. Name of the response spectrum to be used.

  2. -direction cosine of this direction.

  3. -direction cosine of this direction.

  4. -direction cosine of this direction.

  5. Factor multiplying the magnitudes in the response spectrum. Default is 1.0.

Second line (optional):

  1. Name of the response spectrum to be used in the second direction.

  2. -direction cosine of this direction. This direction must be at a right angle to the direction defined above.

  3. -direction cosine of this direction. This direction must be at a right angle to the direction defined above.

  4. -direction cosine of this direction. This direction must be at a right angle to the direction defined above.

  5. Factor multiplying the magnitudes in the response spectrum. Default is 1.0.

Third line (optional):

  1. Name of the response spectrum to be used in the third direction.

  2. -direction cosine of this direction. This direction must be at right angles to the two directions defined above.

  3. -direction cosine of this direction. This direction must be at right angles to the two directions defined above.

  4. -direction cosine of this direction. This direction must be at right angles to the two directions defined above.

  5. Factor multiplying the magnitudes in the response spectrum. Default is 1.0.