Choosing When to Integrate Shell Sections

You can integrate the shell section before the analysis or during the analysis.

Integration determines how the app calculates the cross-sectional behavior of the shell section.

  • Integrate the section before the analysis to calculate the cross-sectional behavior by linear moment-bending and force-membrane strain relationships. This option is beneficial if the response of the shell is linear elastic.
  • Integrate the section during the analysis to calculate the cross-sectional behavior by numerical integration through the shell thickness. This option is beneficial if the shell material includes nonlinear behavior.

This task shows you how to:

See Also
Defining Shell Section Properties

Integrate Shell Sections Before the Analysis

  1. From the Properties section of the action bar, click Shell Section .
  2. Expand the Advanced section.
  3. Select Integrate section before analysis.
  4. From the Offset definition options, select one of the following:
    OptionDescription
    None The geometry support for the shell and the center of the shell thickness are coincident.
    Specify distance Distance (measured along the positive normal direction of the shell) between the geometry support and the center of the shell thickness.
    Ratio of thickness Distance specified as a fraction of the shell thickness (and measured along the positive normal direction of the shell) between the geometry support and the center of the shell thickness.
    Top surface The geometry support for the shell represents the top surface of the shell.
    Bottom surface The geometry support for the shell represents the bottom surface of the shell.
  5. From the Poisson definition options, select one of the following:
    OptionDescription
    Default The shell thickness can change during the simulation based on a Poisson's strain calculated by Abaqus.
    Specify value Directly specify a Poisson's ratio representing the shell thickness direction behavior.
    Calculate from strain and material properties This option is not supported for integration before analysis. If you add it, it generates a diagnostics error and prevents running the simulation.
    Use elastic portion of material The Poisson's ratio representing the shell thickness direction behavior is calculated based on the elastic portion of the material definition.
  6. Click OK.

Integrate Shell Sections During the Analysis

  1. From the Properties section of the action bar, click Shell Section .
  2. Expand the Advanced section.
  3. Clear Integrate section before analysis.
  4. From the Integration scheme options, select one of the following:
    OptionDescription
    Simpson's rule Use this integration method if results output on the shell surfaces is required.
    Gauss quadrature Use this integration method only in cases where results on the shell surfaces are not required (there are no integration points on the shell surfaces).
  5. From the Offset definition options, select one of the following:
    OptionDescription
    None The geometry support for the shell and the center of the shell thickness are coincident.
    Specify distance Distance (measured along the positive normal direction of the shell) between the geometry support and the center of the shell thickness.
    Ratio of thickness Distance specified as a fraction of the shell thickness (and measured along the positive normal direction of the shell) between the geometry support and the center of the shell thickness.
    Top surface The geometry support for the shell represents the top surface of the shell.
    Bottom surface The geometry support for the shell represents the bottom surface of the shell.
  6. From the Poisson definition options, select one of the following:
    OptionDescription
    Default The shell thickness can change during the simulation based on a Poisson's strain calculated by Abaqus.
    Specify value Directly specify a Poisson's ratio representing the shell thickness direction behavior.
    Calculate from strain and material properties The strain in the shell thickness direction under plane stress conditions is a function of the membrane strains and the in-plane material properties. You can only use this option in explicit dynamic steps.
    Use elastic portion of material The Poisson's ratio representing the shell thickness direction behavior is calculated based on the elastic portion of the material definition.
  7. Click OK.