Openings in the webs of I-shaped steel beams can be specified in the Modeler. During optimization or analysis of the beam, the effects of the web openings on the beam are considered.

If necessary, the program will design stiffeners above and below the openings. The criteria for the stiffeners can be specified in the Web Opening Criteria dialog box.

When an opening has been assigned to a beam, the opening information and stiffener design is shown on the View/Update dialog box. That information includes the location of the opening (measured along the horizontal projection, even for sloping beams), the span end from which the distance is measured, the span in which the opening occurs (Left Cantilever, MidSpan, or Right Cantilever), the position within the depth of the web (e.g., Centered, distance from top of beam to top of opening, etc.), shape (Rectangular or Circular), and height H and width B of a rectangular opening or Diameter of a circular opening. The Stiffener Design data includes the width, thickness and length of the stiffener plates, the number of sides on which they occur, and the weld size (full length, both sides of each stiffener). If the opening or stiffeners fail any design requirements, "Fail" is indicated.

Note that when stiffeners are used, they are in pairs, one stiffener plate above and one below the opening; both stiffener plates are the same size. They may occur on one side of the beam web or both sides of the beam web. Often, no stiffeners are required.

To modify the web opening data or stiffener design, select the Modify >> button.

When Optimize is invoked, the beam is optimized and sized to satisfy the requirements of the web openings, and the need for stiffeners is determined and the size optimized accordingly. Any modifications to the opening geometry made using the Modify >> command will be used, but any modifications to the stiffener data will be discarded (and the stiffeners will be optimized).

When Analyze is invoked, the selected beam will be checked for the current web opening information, and design warnings given if the web openings fail for any reason. The stiffeners will be optimized as required, unless the stiffener data has been modified using the Modify >> command, in which case the current stiffener data will be checked and design warnings given if the stiffeners fail.

When Update Database is invoked, the opening and stiffener designs are saved to the database, including any changes made using the Modify >> command.