Abstract：In order to investigate the distortional buckling behavior of 550MPa high strength cold-formed thin-walled channel flexural members, 12 groups of static tests of high strength cold-formed thin-walled channel flexural members with 3 kinds of edge stiffeners including upright, inclined and complex edge stiffeners were conducted, including 6 pure bending tests and 6 non-pure bending tests. It is indicated that the edge stiffener is a key factor that influences the member’s distortional buckling or interaction between local and distortional buckling. The bending strength of non-pure bending members is higher than that of pure bending members for the same edge stiffener. Moreover, the increased magnitude is related to the member’s buckling modes. For the members in which only distortional buckling occurs, the increased magnitude is the greatest. For the members in which interaction between local and distortional buckling occurs, the increased magnitude of members whose failure is caused by distortional buckling takes the second place, and the increased magnitude of members whose failure is caused by local buckling is the least.
