The program designs web openings in conformance with AISC Design Guide #2 when an AISC code is selected.

Although Design Guide #2 was written prior to the publication of AISC 360, the program designs web openings in conformance with AISC 360 when that is the selected code. Some modifications were made to the implementation of the requirements in Design Guide #2 to align those requirements with those of AISC 360. For example:

• For AISC 360 LRFD the Φ factor used for composite design is 0.9 rather than 0.85.
• For AISC 360 ASD the capacities and checks are calculated as for LRFD, except the Ω factor and the ASD Load Combinations are used. This also affects the fillet weld capacity on the stiffeners.

The provisions of Design Guide #2 are not valid for steel with Fy greater than 65 ksi. The program does not verify that this requirement is met; web openings should not be assigned to beams with Fy greater than 65 ksi.

Equations (3-6) through (3-10) and the analogous Equations (5-10) through (5-17) are simplified approximate equations. The program does not use those; rather, it calculates the actual plastic moment capacities of the cross section.

Stiffeners are assumed to be placed 0.5" clear from the edge of opening, rather than flush with the opening. Stiffener welds are assumed to be continuous on both sides of the stiffener plate.

Requirement 3.7(a)3 addresses buckling of the tee-shaped compression zone. Few definitive requirements are given. As specified, this check is only performed for precomposite and noncomposite tees in compression; it is not performed for the composite tee. For unreinforced openings, this check is not performed on tees whose aspect ratio is less than or equal to 4.0. Based on clarification from AISC, this check is also not required for reinforced openings, so this check is not performed on reinforced tees whose aspect ratio is less than or equal to 4.0. Otherwise, for reinforced openings the check is performed (the design guide ambiguously states that it is only required for large openings in regions of high moment), and the capacity of the tee is calculated ignoring any contribution of stiffeners. The axial load in the tee is simply computed as the ultimate moment at the opening divided by the moment arm between the elastic neutral axes of the top and bottom tee. No moment load in the tee (the so-called "secondary" moment) is considered. Thus the tee is "investigated as an axially loaded column."

Requirement 3.7(a)4 addresses lateral buckling. This requirement is not checked by the program. Users should satisfy themselves that this requirement has been satisfied for each opening. For LRFD design the program does use the reduced torsional constant, J, per Equation (3-26), in the design of the beam.

Requirement 3.7(c)2 has an additional requirement for shear connectors, with clarification given in Section 5.7(c)2. The program does not check this requirement, nor does it add additional studs to conform to this requirement. If the studs called for by the program are greater than or equal to 2 studs per foot in the region specified in the Design Guide, no additional studs are required; otherwise additional studs in the region specified in the Design Guide should be indicated on the structural drawings.

The effects of web openings on the beam deflection may be significant. However, the approximate procedures given in the design guide are not general enough to universally apply to the opening configurations possible in the program, so no procedures were implemented. Thus the deflections reported by the program do not consider the additional effects of the openings. The engineer may consider applying a more stringent deflection criteria to these beams to account for the fact that the beams will deflect more than reported.