Exercise 3 – Modifying the Equipment Support Structure
5.8 Creating and Modifying a Ring GENSEC A Worked Example
5.8.2 Support Beam Requirements
The support beam will be modelled using a Parallel Flange Channel. Click the Set Default Profile Specification button in the Beams & Columns toolbar.
From the British Standard specification select the Generic Type Parallel Flg Channels then select the 200x75x23PFC profile. Set the
justification to LTOC leaving the Member line and the Joint line set to NA. Click the Apply button then the Dismiss button.
The storage areas for the new beam also need to be set. In the Design Explorer navigate to STRU
BUILDING_01_LEVEL_01 and open the hierarchy
tree. Navigate to FRMW B01_LEVEL_01_BEAMS and set this framework for the node and section storage areas.
The support beam will be constructed as an arc that broadly follows the curvature of the floor slab and ties into the south west and south east columns as shown.
5.8.3 3D Aid Constructs – Working Planes and Line Constructs
The support beam needs to be positioned such that the top of the section coincides with the underside of the floor slab. This can be achieved in a number of ways during element creation, however one means of ensuring the correct elevation is to establish a Working Plane.A Working Plane may be a plane or a grid and can be used to control positioning operations. If a working plane is active, picked positions will be projected onto the plane. Only one Working Plane may be active at any given time.
A Working Plane can be created explicitly using the Utilities > Working Plane… option from the main menu. Alternatively, a 3D Aid Plane or Grid can be created and then made to be the active Working Plane.
Select Utilities > Working Plane… from the main menu to display the Working
Plane form. Navigate to the Define form menu and select the Define > Plane…
The Working Plane form is divided into two significant frames; Options and Position & Orientation. The functionality of these frames is similar to that described for Plant Grids.
The Options area of the form enables the user to Label the plane, display the plane Axes, and toggle between a filled and unfilled graphical representation of the plane (if displayed). The
Size of the graphical representation of the plane can also be
adjusted by changing the values in the X and Y textboxes. The Position & Orientation area of the form enables the user to position the plane origin and orientate the plane. Planes can be positioned explicitly by entering co-ordinates, or through
graphical selections.
Clicking the OK button on the form sets the defined plane as the
active Working Plane, automatically checking the Active and
Visible checkboxes.
A graphical selection will be made to position (and orientate) the working plane.Set the Positioning Control toolbar Pick Method to Element and the Pick Type to Snap.
Change the 3D view to show a plan view north. Select one of the beams running from East to West near the North East corner then click the OK button.
Aid graphics showing the working
plane with axis at the plane origin will be displayed.
The aid graphics can be removed from the view by un-checking the Visible setting on the Working Plane form.
Dismiss the Working Plane form. With the working plane suitably defined additional circle and line aid constructs can be created. Select Utilities > Constructs… from the main menu. The 3D Aid Constructs form is displayed.
Select Create > Circle > Toolbar from the form menu to display the select the Circles toolbar. An arc shaped aid line will be created from the existing geometry of the Level 01 floor slab.
Click the Through Three Points button on the Circles toolbar. This action instigates the Events Driven
Graphics (EDG) mode. In the Primary Prompt area the user is instructed to make a graphical selection for
the first point of the aid line. Navigate to the Positioning Control toolbar and change the Pick Type to Graphics and the Pick Method to Snap.
Select the Southeast corner of the floor slab. This marks the start position of the arc aid line. As a working plane is active, the picked point is transposed to the working plane. An aid graphic indicating the point selection sequence is displayed.
The second pick point needs to be made approximately mid way around the circumference of the curved floor. Position the cursor over the floor slab then hold down the left mouse button. The cursor will change to a parallelogram shape. While holding down the left mouse button move the cursor toward the edge of the curve. When the cursor shape changes to a dumbell shape release the mouse button.
The third pick point defines the end of the arc aid line. Select the Southwest corner of the floor slab. On selecting the final pick point the aid graphic will be displayed with an arrow at the origin of the arc and two text boxes at the start and end of the defined angle.
To assist in creating the Gensec a further aid line, bisecting the arc aid line, will be created. Dismiss the
Circles toolbar then select Create > Line > Toolbar… from the 3D Aid Constructs form. Click the Bisect
the Picked Lines button from the Lines toolbar. Two lines need to be selected as noted in the primary prompt area.
Select the line defined between the arc origin and the arc start position. For the second line select the line defined between the arc origin and the arc end position. The aid graphics should now look similar to the picture below.
The arc aid graphic is based on the geometry of the floor slab. The position of the support beams must account for the exterior wall and the smaller sized floor of Level 02. Rather than reposition the beam after it is created the aid graphics will be modified to ensure the beams are created the correct position
Close the Lines toolbar then select Modify > Definition… from the 3D
Aid Constructs form. In the primary prompt area the user is asked to
pick the aid to be modified. Graphically select the arc aid line. The
Modify Circle form will be displayed.
The origin of the aid graphic needs to be positioned 200mm to the North. In the Position frame lock the West and Up co-ordinate by selecting the checkbox adjacent to each co-ordinate. In the North co- ordinate textbox type 331223.24 then press the Enter key.
The aid graphics will display the proposed new position. Click the OK button to modify the position of the aid. Dismiss the 3D Aid Constructs form.
The completed aid graphics should look similar to the picture below.