Create web openings in steel members

You can add square, rectangular, and circular web openings to beams and columns either by specified them manually, or by using a Quick layout option. FABSEC^® beams can also have elongated openings specified.

Restriction:

Although web openings can be added to steel beams and columns, they are only considered in the design of:
- Non-composite beams designed to US codes, BS codes, or Eurocodes
- Composite beams designed to US codes, BS codes, or Eurocodes
Web openings are only valid in check design. If the auto design flag is switched on the openings will be removed.

Web opening creation methods

Note: Web openings can only be added to members set to manual (as opposed to automatic) design. They are specified from the Web openings page of the Properties dialog box. Web openings cannot be specified from the Properties window.

The Quick layout method adds web openings to meet the geometric and proximity recommendations published by the SCI. With this method, Tekla Structural Designer creates web openings at the maximum depth and spaced at the minimum centers recommended for the section size.

With the Quick layout option cleared you can also define web openings manually using one of the following two methods:

Clicking the Add button adds a new line to the web openings grid and allows you to define the geometric properties of the opening.
Clicking the Add... button opens the Web opening dialog box where you can get more help and guidance when defining the opening.

Both manual methods use and signs to indicate faulty data when defining the opening parameters.

For more assistance, hover the mouse pointer over a or sign.

The Web opening dialog box

In the Web opening dialog box, you can use the following buttons to automatically define the position of the web opening:

The Center button positions the opening on the center of the member.
The Auto button positions the opening to meet the spacing recommendations by the SCI.

As web openings are defined, they are immediately visible in the diagram in the Web opening dialog box.

Tekla Structural Designer also performs design checks when you are defining web openings in the Web opening dialog box. The checked areas are end posts, web posts, web opening dimensions and tee dimensions.

The and signs in the Web opening dialog box help you to decide whether to make any adjustments to the opening parameters before Tekla Structural Designer checks the design.

Note: The design checks carried out at the current stage are geometric checks only. Compliance with recommended limits is no guarantee that the opening will pass the subsequent engineering design checks.

Add web openings using the Quick layout option

Using the Quick layout method allows you to create maximum depth openings spaced at the minimum centers, appropriate to the section size.

Click the member to which you want to add web openings.
In the Properties window, ensure that the Autodesign option is cleared.
Right-click the member, and in the context menu, select Edit [element name].

The Properties dialog box opens.
Go to Web openings.
Select the Quick layout option.
In the Label openings from list, select where you want to start the setting out from.
In the Type column, select the web opening type.
Data for the first web opening is automatically created as follows:
- I_O: the length of the opening (applies to rectangular openings only)
- d_O: the depth of the opening
- L_CR: the distance from the setting out point to the center of the opening
- L_C: the distance from the end 1 on the member to the center of the opening
- d_C: the distance from the top of the member to the center of the opening
- L_CR relative to: indicates the setting out point from which L_CR is measured.
- Nr. rel. to: specifies an existing opening number that you want to use as the setting out point for the new opening.
  
  Nr. rel. to only applies if you selected one of the Opening -> options in the L_CR relative to column.
If necessary, in the Stiffening column, select the location of stiffening.
1. Type the details of the stiffeners manually as follows:
  - d_S: depth of the stiffener
  - t_S: thickness of the stiffener
  - L_S: length of the stiffener
  - e_S: the distance from the edge of the opening to the center of the stiffener
To create further openings from the selected setting out points, click Add and select the opening type.

Tip: You can use the Label openings from list to switch to a new setting out point for the next opening at any point.
When you have created the desired openings, click OK.

Add web openings manually

Click the member to which you want to add web openings.
In the Properties window, ensure that the Autodesign option is cleared.
Right-click the member, and in the context menu, select Edit [element name].

The Properties dialog box opens.
Go to Web openings.
Ensure that the Quick layout option is not selected.
In the Label openings from list, select where you want to start the setting out from.
Click Add...
In the Type column, select the web opening type.
Specify the following details for the opening:
- I_O: the length of the opening (applies to rectangular openings only)
- d_O: the depth of the opening
- L_CR: the distance from the setting out point to the center of the opening
- L_C: the distance from the end 1 on the member to the center of the opening
- d_C: the distance from the top of the member to the center of the opening
  
  Tip: Click Center for dC to be automatically calculated to position the opening centrally in the section depth.
- L_CR relative to: indicates the setting out point from which L_CR is measured.
- Nr. rel. to: specifies an existing opening number that you want to use as the setting out point for the new opening.
  
  Nr. rel. to only applies if you selected one of the Opening -> options in the L_CR relative to column.
If necessary, in the Stiffening column, select the location of stiffening.
1. Type the details of the stiffeners manually as follows:
  - d_S: depth of the stiffener
  - t_S: thickness of the stiffener
  - L_S: length of the stiffener
  - e_S: the distance from the edge of the opening to the center of the stiffener
To create the opening, click OK.
To create further openings, do one of the following:
- To create multiple copies of a selected opening, click Copy...
- To create a single opening of a different size or spacing, click Add...