Part 4 in the Handbook of Steel Construction contains tables of factored axial compressive resistances. For a small number of compression members, the width-to-thickness ratio of the flanges and/or web exceeds the limits given in CSA S16-14 Table 1.

The compressive resistance of members subject to elastic local buckling (Class 4 sections) may be calculated using either the effective area method or the effective yield stress method, according to S16‑14 Clause 13.3.5. It is also possible to use both methods and retain the greater resistance between the two. The effective area method is illustrated in the accompanying figure.


The method of calculation for Class 4 sections in the various tables of Part 4 is as follows:

(a) Effective area method, Clause 13.3.5(a)

(b) Effective yield stress method, Clause 13.3.5(b)

  • W-Shapes, pp. 4-17 to 4-31:
Greater of methods (a) and (b)
  • HSS, pp. 4-32 to 4-100:
Mostly method (a), but a small number of HSS calculated using (b) and identified with the symbol “#”.
  • Angle struts, pp. 4-116 to 4-147
Method (a)