13.3.1 Beam Limitations
Beams shall satisfy the following limitations:
- (1) Beams shall be rolled wide-flange or welded built-up I-shaped members conforming to the requirements in Section 2.3.
- (2) Beam depth, , is limited to a maximum of W24 (W610) for rolled shapes. The depth of built-up members shall not exceed the depth permitted for rolled wide-flange shapes.
- (3) Beam weight is limited to a maximum of 55 lb/ft (82 kg/m).
- (4) Beam flange thickness is limited to a maximum of 5/8 in. (16 mm).
- (5) The clear span-to-depth ratio of the beam shall be limited to 9 or greater for both SMF and IMF systems.
- (6) Width-to-thickness ratios for the flanges and web of the beam shall conform to the limits of the AISC Seismic Provisions.
- (7) Lateral bracing of beams shall be in conformance with the AISC Seismic Provisions for SMF or IMF systems, as applicable. To satisfy the requirements for lateral bracing at plastic hinges, lateral bracing shall be provided at a location on the beam that is between and beyond the bolt farthest from the face of the column. No attachment of lateral bracing shall be made to the beam within the protected zone.
Exception: For both SMF and IMF systems, where the beam supports a concrete structural slab that is connected between the protected zones with welded steel headed stud anchors, spaced a maximum of 12 in (300 mm) on center, supplemental lateral bracing at plastic hinges is not required.
- (8) The protected zone consists of the T-stubs and the portion of the beam between the face of the column and one beam depth, d, beyond the bolt farthest from the face of the column.
13.3.2 Column Limitations
Columns shall satisfy the following limitations:
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(1) Columns shall be any of the rolled wide-flange shapes, built-up I-shapes, or flanged cruciform sections permitted in Section 2.3.
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(2) The beam shall be connected to the flange of the column.
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(3) Rolled shape column depth shall be limited to W36 (W920) maximum when a concrete structural slab is provided. In the absence of a concrete structural slab, rolled shape column depth is limited to W14 (W360) maximum. The depth of built-up I-shaped columns shall not exceed that for rolled shapes. Flanged cruciform columns shall not have a width or depth greater than the depth allowed for rolled shapes.
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(4) Width-to-thickness ratios for the flanges and web of the column shall conform to the applicable limits of the AISCE Seismic Provisions.
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(5) Lateral bracing of columns shall conform to the applicable limits of the AISC Seismic Provisions.