15.3.1 Beam Limitations
Beams shall satisfy the following limitations:
- (1) Beams shall be rolled wide-flange or built-up I-shaped members conforming to the requirements of Section 2.3.
- (2) Beam depth shall be limited to a maximum of W40 (W1020) for rolled shapes. Depth of built-up sections shall not exceed the depth permitted for rolled wide-flange shapes.
- (3) Beam weight shall be limited to a maximum of 309 lb/ft (460 kg/m).
- (4) There are no limits on the beam web width-to-thickness ratio beyond those listed in the AISC Specification. The beam flange width-to-thickness ratio shall not exceed per AISC Specification Table B4.1b.
- (5) Lateral bracing of beams and joints—there are no requirements for stability bracing of beams or joints beyond those in the AISCSpecification.
15.3.2 Column Limitations
Columns shall satisfy the following limitations:
- (1) Columns shall be any of the shapes permitted in Section 2.3.
- (2) The beam shall be connected to the column with connection plates.
- (3) Rolled shape column depth shall be limited to W36 (W920) maximum. Column depth of built-up sections shall not exceed the depth permitted for rolled wide-flange shapes. Built-up box-columns shall not have a width exceeding 17 in. (430 mm).
- (4) There is no limit on weight per foot of columns.
- (5) There are no additional requirements for flange thickness.
- (6) Width-to-thickness ratios for the flanges and the web of columns shall conform to the requirements of the AISC Seismic Provisions.
- (7) Lateral bracing of columns shall conform to the requirements of the AISC Seismic Provisions.
15.3.3 Plate Limitations
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(1) All connection plates shall be fabricated from structural steel that complies with ASTM A572/A572M Grade 50 (Grade 345). Fuse plates shall be fabricated from plates that have mill certified tensile strengths less than or equal to 85 ksi (590 MPa), unless independent material testing determines that the tensile strength is less than or equal to 85 ksi (590 MPa).
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(2) The thickness of the external continuity plates, top plates, and fuse plates shall not exceed 2 in. (50 mm) and shall not be less than 1/2 in. (13 mm).
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(3) The width of the yielding regions in the fuse plates shall not exceed 4 in. (100 mm) and shall not be less than 1½ in. (38 mm).
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(4) The width-to-thickness ratio of the yielding regions in the fuse plates shall not exceed 4.25 and shall not be less than 1.5.
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(5) The width-to-depth ratio of the yielding regions in the fuse plates shall not exceed 1.25 and shall not be less than 0.5.
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(6) The protected zone of the connection consists of the fuse plate.