STAAD.Pro Help

T.1 Specifying member offsets

Member 2 (the beam) actually spans only the clear distance between the column faces rather than the center to center distance. This is modeled by specifying offsets.

Member 2 is offset at the start joint by 6 inches in the global X direction (and 0.0 and 0.0 in Y and Z directions). The same member is offset by negative 6.0 inches at its end joint.

The STAAD input file commands generated are:

MEMBER OFFSET
2 START 6.0 0.0 0.0 
2 END -6.0 0.0 0.0
  1. Select member 2 by clicking on it in the view window.
    Note: If the beam cursor isn't currently active, select the Beam Cursor tool in the Selection group on the Geometry ribbon tab.

    The selected member will be highlighted.

  2. Select the Specifications page on the Analytical Modeling page bar. The Specifications - Whole Structure dialog opens. Member releases, offsets, and other beam specifications are defined here.
  3. Click Beam.

    The Member Specification dialog opens.

  4. Specify the member start offset:
    1. Select the Offset tab.
    2. Select Start as the Location.
    3. Type 6.0(in.) in the X offset field.

      Leave the Direction as Global. It is convenient to define the offset at the start node in the X direction. Since the beam member is aligned with the global X axis, there is no difference between choosing a global or local frame of reference.

    4. Click Assign.
    The dialog closes and the offset specification is added to the start of member 2. This is displayed visually on the member as well as listed in the Specification list in the Specifications - Whole Structure dialog.
  5. On the Specification ribbon tab, select the Beam > Offset tool in the Specifications group.

    The Member Specification dialog opens to the Offsets tab.

  6. Specify the member end offset:
    1. Select End as the Location.
    2. Type -6.0(in.) in the X offset field.
    3. Click Assign.
    The dialog closes and the offset specification is added to the start of member 2.
Tip: Alternatively to steps 5 and 6, you can repeat steps 3 and 4, except for selecting the End option and providing a value of -6.0 for X. This procedure is used to demonstrate two methods to complete a similar task.

The model after both start and end offsets are assigned

Click anywhere in the drawing area to deselect the member.

Tip: Remember to save your work by either click Save on the File ribbon tab , the Save tool, or pressing <CTRL+S>.