Area Springs

Form: Area Spring Properties, Area Spring Property Data

Use the Define menu > Spring Properties > Area Springs command to access the Area Spring Properties form and add, modify, or delete a named area spring  with a specified spring constraint per unit area that can be assigned to an area object that lies in the model datum plane. Area springs are defined as force/length/area.

• Add New Property button. Click this button to access the Area Spring Property Data form, and define the new property:

• • General Data: Input the name of the spring property in the edit box, set the display color and click the Modify/Show Notes button to add area spring property notes.

  • Spring Constants / Unit Area: Input translational spring stiffness values per unit area in the local 1, 2 and 3 directions. The translational stiffness in the local 3 direction may be linear, or tension or compression only depending on the selection made in the Nonlinear Option area.

  • Nonlinear Option for Local 3 Direction: Click None if the springs are linear, or Tension Only if they should work only in tension, or Compression Only if they are to work only in compression. The compression only option can be used to model uplift on a foundation. The program assumes that a displacement in the positive 3 direction places the corresponding spring in tension, while a displacement in the negative 3 direction places the corresponding spring in compression.

• Add Copy of Property button.

• 1.  Highlight one of the spring properties in the Area Spring Property list and click this button to access the Area Spring Property Data form.

  2. All edit boxes, drop-down lists, and option selections (except for the Property Name) on that form will be populated with values identical to those of the highlighted spring property. Values may be revised as necessary and then saved to create a new spring property.

• Modify/Show Property button.

• 1. Highlight one of the spring properties in the Area Spring Property list and click this button to access the property specific Area Spring Property Data form, which displays the various values that comprise the property definition.

  2. Review and revise the data as necessary.

• Delete Property button.

• 1. Highlight one of the spring properties in the Area Spring Property list.

  2. Click this button to remove this property from the model.

Note: "None" is included in the Springs list (on the  Shell Assignments - Area Springs  form) when using the Assign menu > Shell > Area Springs command. Selecting the None property definition and assigning it to an object removes any definition previously assigned to that object.

TIP: The Calculator feature can be used to assist with mathematical operations during data entry. Place the mouse pointer/cursor in an edit box, hold down the Shift key and double click the left mouse button to open the form.