Performing a Response Spectrum Analysis

  1. Click Simulation > Study.
    1. Under Type, select Linear Dynamic linra_dynamic.png Button.
    2. Under Options, select Response Spectrum Analysis .
  2. Define the frequency and response spectrum options of the study. In the Simulation study tree, right-click the study icon and click Properties.
  3. Define material for each body. Right-click its icon and select Apply/Edit Material.
    Composite shells are not supported in a response spectrum study.
  4. Under Connections ST_Connections.gif, define contact sets and any needed connectors.
    Bonded contact, spring and edge welds connector are supported.
  5. To define fixtures, right-click Fixtures ST_Fixtures.gif and select from the options.
  6. Right-click External Loads and select Uniform Base Excitation or Selected Base Excitation. This defines the base excitation (uniform or selected) in terms of a given displacement, velocity, or acceleration response spectrum.
    Distributed mass is also supported.
    For uniform base excitation, the response spectrum is applied to all locations that are restrained in the specified global X, Y, or Z directions.

    For selected base excitation, the response spectrum is applied to a selected fixture definition. If the selected fixture has more than one direction, you can select one direction at a time to apply the excitation.

    In a response spectrum analysis study, you can apply multiple response spectra definitions for uniform or selected base excitations. In case of multiple response spectra definitions, the total response is calculated by the square root of the sum of the squares of the individual responses.
  7. Right-click Result Options and select Edit/Define.
    Absolute displacements and velocities are always computed, when you apply selected base excitation.
  8. Mesh the model and run the study.
  9. Right-click Results and select the desired options.
    You can view the model's maximum response values (stresses, displacements, velocities, accelerations) based on the modal combination technique you selected in Step 2.
    If you define multiple response spectra as base excitations, the total response is calculated as the square root of the sum of the squares of the individual responses.