Line Springs

Form: Line Spring Properties, Line Spring Property Data

Use the Define menu > Spring Properties > Line Springs command to access the Line Spring Properties form and add, modify, or delete a line spring property definition that can be assigned to a line object that lies in the model datum plane. Line spring property definitions are used to specify the vertical and rotational spring stiffness values per unit length of line.

Note: The line spring properties also can be accessed by right clicking the Spring Properties sub node, or right clicking on one of the items in the list under this sub node, both under the Properties node on the Model tab in the Model Explorer window.

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

• • 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 line spring property notes.

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

  • Nonlinear Option for Local 2 and 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. These options apply only to vertical springs. The program assumes that a displacement in the positive Z direction places the corresponding spring in tension, while a displacement in the negative Z direction places the corresponding spring in compression.

• Add Copy of Property button.

• 1.  Highlight one of the spring properties in the Line Spring Property list and click this button to access the Line 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 line spring property.

• Modify/Show Property button.

• 1. Highlight one of the spring properties in the Line Spring Property list and click this button to access the property specific Line 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 Line Spring Property list.

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

Note: "None" is included in the Springs list (on the Frame Assignment - Line Springs form) when using the Assign menu > Frame > Line 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.