the edge stiffener must be greater than the required moment of inertia per AISI Section B2,
Effective Widths of Stiffened Elements. When the neutral axis is closer to the tension flange or at
mid-depth on a symmetrical section, the design stress in the tension flange is at yield, and is
calculated based on the compression stress in the flange. Should the neutral axis be closer to
the compression flange than the solution becomes iterative to locate the neutral axis,
compressive stress, and .
(1) Properties of Sections, Section C1. Typically full cross section properties are
used except where reduced or effective element widths are required. A computer program is
needed to efficiently calculate effective section properties
(2) Tension Members, Section C2. Common rules for hole placement and largest
hole reduction is in AISI specification. Currently there are no shear lag provisions in the
specification. However, there will be in the future manual. Also, A307 Bolts are commonly used
in Cold-Formed Steel design.
(3) Flexural Members, Section C3.
(a) Strength for Bending Only, Section C3.1. Reference Yura on member
bracing. For screw down roof systems, brace the C's and Z's at 1/3 points for uplift loads only.
(b) Strength for Shear Only, Section C3.2
(c) Strength for Combined Bending and Shear, Section C3.3.
(d) Web Crippling Strength, Section C3.4.
(e) Combined Bending and Web Crippling Strength, Section C3.5.
(4) Concentrically Loaded Compression Members, Section C4. Torsional-Flexural
Buckling is unique to cold-formed columns and beam-columns. and the Factor of Safety for
Columns is equal to 1.80. Torsional-Flexural Buckling controls most columns.
(a) Sections Not Subject to Torsional or Torsional-Flexural Buckling, Section
(b) Doubly or Singly Symmetric Sections Subject to Torsional or Torsional
Flexural Buckling, Section C4.2
(c) Nonsymmetrical Sections, Section C4.3.
(d) Compression Members Having One Flange Through-Fastened to Deck or
Sheathing, Section C4.4.
(5) Combined Axial Load and Bending, Section C5.
(a) Combined Tensile and Axial Load and Bending, Section C5.1.
(b) Combined Compressive Axial Load and Bending, Section C5.2
(6) Cylindrical Tubular Members, Section C6.
(a) Bending, Section C6.1.
(b) Compression, Section C6.2