Structural Non-Linear Analysis

Run Structural Non-Linear Analysis in SimSolid.


SimSolid performs meshless structural analysis that works on full featured parts and assemblies, is tolerant of geometric imperfections, and runs in seconds to minutes. In this tutorial, you will do the following:
  • Create Structural Non-Linear Analysis (Material and Contact).

Model Description

The following files are needed for this tutorial:
  • Material_Separating_NonLinearity.ssp
  • Stress_strain_curve.csv

Figure 1.
The project file has the following specifications:
  • Material is set to Aluminum for all parts.
  • Regular connections with 0.6mm gap and 0.3mm penetration tolerance.
  • For the sake of analysis, all sliding contacts have been changed to bonded.

Open Project

Open the SimSolid project file.

  1. Start a new SimSolid session.
  2. Click the (Open Project) icon.

    Figure 2.
  3. In the Open project file dialog, choose Material_Separating_NonLinearity.ssp
  4. Click OK.

Define Non-Linear Material

Edit the material database to define non-linear material.

  1. In the main menu, click Settings > Material database.

    Figure 3.
  2. In the Define material database window, click Edit current.

    Figure 4.
  3. In the dialog, right-click on the Sample non linear materials folder and select Add Material from the context menu.

    Figure 5.
  4. Select Add stress-strain curve....
  5. Click Edit.
  6. Import the Stress-strain curve.
    1. In the Stress-strain curve window, click Import CSV.

      Figure 6.
    2. In the File explorer, browse to Stress_strain_curve.csv and click Open.
    3. In the dialog, click OK.

      Figure 7.
    In the Edit Material database dialog, you will see Elasticity Modulus was calculated from the imported Stress-strain curve.

    Figure 8.
  7. Enter other values in the dialog,
    1. For Poisson's ratio, enter 0.3
    2. For Density, enter 7.85e+03.
    3. For Ultimate tensile stress, enter 0.
    4. For Thermal expansion coeff., enter 1.2e-5.
    5. For Thermal conductivity, enter 5.6e+1.
  8. Edit material name to Steel NL.
  9. Click Save material.
  10. Click OK.

Assign Materials

Apply materials to select parts in the assembly.

  1. In the Project Tree, click on the Assembly branch.
  2. In the Project Tree, hold down Control and multi-select parts as shown in Figure 9.
    Figure 9.
  3. Click (Apply material).
  4. In the dialog, click to expand the Sample non-linear materials folder.
  5. Pick Steel NL from the list.
  6. Click Apply to selected parts.

    Figure 10.
  7. Click OK.
    In the Assembly branch of the Project Tree, material properties are identified for each part.

Create Structural Non-Linear Analysis

Setup Non-Linear Separating contact and Material non-linear subcases.

  1. In the main window toolbar, click > Structural non-linear.

    Figure 11.
  2. In the dialog, activate the Separating contact and Material non-linear checkboxes.

    Figure 12.
  3. Click OK.

Edit Contact Conditions

Change the contact conditions to separating/closing.

  1. In the Project Tree, expand the Connections branch.
  2. Hold down Control and multi-select connections as shown in Figure 13.

    Figure 13.
  3. Right-click and select Edit Default contact conditions from the context menu.
  4. In the dialog, select Separating/closing.
  5. Set Friction coefficient to 0.1.
  6. Click OK.

    Figure 14.

Create Immovable Support

Create immovable support.

  1. In the Analysis Workbench, click (Immovable support).
  2. In the dialog, verify the Faces radio button is selected.
  3. In the modeling window, select the faces shown in orange in Figure 15.

    Figure 15.
  4. Click OK.

Tighten Bolts

Create a bolt tightening load.

  1. On the Analysis Workbench, select (Bolt tightening).
  2. In the modeling window, select the bolts as shown in Figure 16.

    Figure 16.
  3. For Thread pitch, enter 1.25.
  4. For Number of turns, enter 1.
  5. Click OK.

Define Load

Apply Force load.

  1. In the workbench toolbar, select > Force/Displacement.

    Figure 17.
  2. In the dialog, select the Face radio button.
  3. Select the face as shown in Figure 18.

    Figure 18.
  4. Under Total force or displacement along axes, for Z enter -10000.
  5. Click OK.

Run Analysis

Solve the analysis.

  1. In the Project Tree, open the Analysis Workbench.
  2. Click (Solve).

Review Results

Plot the displacement contour.

  1. On the Analysis workbench toolbar, click the (Results plot) icon.
  2. In the menu, select Displacement Magnitude.
    The Legend window will appear showing the contour plot. The Results window will appear. You can review the plot for different zones.

    Figure 19.

Review Bolt Forces

View a table showing bolt forces in the analysis.

  1. On the Analysis Workbench, toolbar, select (Bolt/Nut resultant forces).

    Figure 20.
    The Bolt/nut forces dialog will display.
  2. Optional: You can save forces as a CSV file by clicking Save CSV in the dialog.

Review Contact Response

View a table showing contact response (opening, slippage, and traction at contacts).

On the Analysis Workbench, toolbar, select (Contact response).
Figure 21.
The Response at connections dialog will display.