T.2 Specifying geometric constants

You need to orient member 4 so that its longer edges (sides parallel to local Y axis) are parallel to the global Z axis. This requires applying a beta angle of 90 degrees.

In the absence of any explicit instructions, STAAD.Pro will orient the beams and columns of the structure in a predefined way. Orientation refers to the directions along which the width and depth of the cross section are aligned with respect to the global axis system. The rules which dictate this default orientation are explained in General Engineering Theory.

The STAAD input file commands generated are:

BETA 90 MEMB 4

Select the Properties page in the Analytical Modeling page control bar. The Properties dialog opens.
On the Properties dialog, select the Beta Angle tab.
Click Create Beta Angle.
The Beta Angle dialog opens.
Type 90 in the Angle in Degrees field.
Click OK. The property Beta 90 is added to the beta angles list.
Select the property Beta 90.
Assign the beta angle to member 4:
1. Select the Use Cursor to Assign option in the Assignment Method group.
2. Click Assign. The mouse pointer changes to
3. In the view window, click on member 4.
4. To stop assigning members, either:
  
  click Assigning
  
  or
  press the <Esc> key.
To view the orientation of the member local axes:

right-click in the view window and select Labels from the pop-up menu, check the option for Beam Orientation, and click Apply.

or
press <Shift+O>.

The Beta Angle applied to Member 4

Alternatively, you can assign a beta angle to a selected member set. On the Specification ribbon tab, select the Beam > Beta Angle tool in the Specifications group. Type the beta Angle in Degrees to use. Make sure that the To Selection option is selected and then click OK.