Experimental Study and Direct Strength Method for Cold-Formed Steel Built-Up I-Sectional Columns under Axial Compression

Figure 10

Buckling modes of built-up columns with the nominal length of 1500 mm. (a) Local buckling in web. (b) Local buckling in the flange. (c) Distortional buckling + local buckling in web. (d) Plastic crush.

(a)

(b)

(c)

(d)