§2213.7.2 Panel Zone

The moment strength of a member is calculated as Ms = Z x Fy, no over-strength is applied to the beams.

Load combination 1.0D + 1.0L + 1.85E is created internally to RAM Frame to perform this check.

The shear in the column above the joint is considered when calculating the panel zone shear force using the above generated load combination.

Panel zone strength is a function of the beam depth. Where one panel zone capacity is reported it is based on the deepest beam framing into the column flange (which provides the smallest capacity).

When calculating the panel zone strength per (13-1) the contribution of the web plate is added to that of the column web. The doubler capacity is calculated independent of the column web using its own yield strength value. The depth of the web plate (doubler) is taken as the clear distance between column flanges.

§2213.7.3 Width Thickness Ratio

The axial value used to calculate the web d/tw limit for I-Sections based on Section 2251N7 is the maximum axial load from all standard provision load combinations. As this is a plastic capacity check the axial load used to perform this check should be the result of a factored load combination. Per AISC 9^th, page 5-184, RAM Frame calculates the largest factored axial load on the member by multiplying the standard provision load combinations force by 1.7 if there are no lateral load case, and by 1.3 if there are lateral load cases.

The width to thickness ratio of girders is checked against the compact member limits of the AISC ASD specification, except as modified in 2213.7.2.

§2213.7.4. Continuity Plates

Stiffeners are only designed for flange bending requirement of chapter K in AISC ASD 9^th Edition.

The required area of the stiffeners is calculated as the difference in the design force (Pbf) and the flange capacity (Rn) divided by the stiffener yield strength.

§2213.7.5. Strength Ratio

Mpz is calculated as the panel zone shear capacity multiplied by the deepest beam section framing into the column flange.

When calculating the shear capacity of a story for exception 2, all lateral steel columns, not only those columns of the special moment frame type, are considered. Only the major axis shear capacity of the member is considered.

§2213.7.7 Girder-Column Joint Restraint

§2213.7.7.1 Restrained Joint – A joint is considered restrained if contained within a deck, is a beam frames into the weak axis of the column, or by the user specifying that the column is braced.

If the user indicates that the minor axis of the joint column is unbraced then the physical bracing (deck or beams) is ignored and the joint is considered unrestrained.

The deck is only considered to brace the joint at the elevation of the top flange of the beams framing into the flanges of the column.

If a beam is determined to frame into the minor axis of the column at the joint, then RAM Frame assumes that the joint is restrained at the elevation of both the top and bottom flanges of the framing beams.

§2213.8.2.3. Lateral-Force Distribution

The lateral-force distribution check of Section 2213.8.2.3 is only performed if the user indicates that frame numbers are to be used to define a line of bracing (refer to Criteria-Codes dialog).

When performing the lateral-force distribution check of Section 2213.8.2.3, RAM Frame only accumulates loads for those braces with the same frame numbers.

§2213.8.2.5. Compression Elements in Braces

The flat wall dimension per the AISC-ASD is used to calculate the width-thickness ratio for tube sections when checking §2213.8.2.5.

§2213.8.4.2 K-Type Bracing

K-Type frames are only allowed if the user indicates to apply one and two story exceptions in the Criteria-Codes dialog.

All the members of the structure designated as type K-Frame will be required to meet the requirements of §2213.8.5.

§2213.8.5. One- and Two- Story Buildings

Section 2213.8.5 requires that the strength of all braces meet the increased strength demands. RAM Frame only performs this check if all the braces of the frame type have pinned connections (i.e., axial only load). This is because the specification provides no indication of how to calculate the bending "strength" of a member that may fail in an elastic fashion (e.g. due to lateral torsional buckling).