抄録
The thin walled struts under axial compressive load may suffer the wall buckling, which is the appearance of wave form wrinkles in its own wall. The critical load for the occurence of this wall buckling of the thin plane walled profiles was investigated theoretically and proved to be expressed in the form
pkw=KmE/12(1-νν2)·(s/a)(s/a)2
where pkw critical wall buckling stress,
Km coefficient peculiar to the form of the profile,
E Young's modulus,
ν Poisson's ratio,
s thickness of the wall,
a width of one plane of the wall which is taken as a standard.
The values of Km for the closed and open profiles were calculated.
The max. strength of the strut after the wall buckling, which is called in this paper the wall buckling strength, was also studied mainly expenimentally and found to be different fundamentally whether the section form permits the redistribution of stress in the wall, after the wall buckles, or not. The wall buckling strength of the profiles such as channel, which permit no stress redistribution, is the same as the critical wall buckling stress. But that strength of the profiles such as _??_ _??_ _??_, in which the stresses in the wall redistribute after the wall buckling, may be expressed
where pk wall buckling strength,
σp proportiol limit which is to be determined from the wall buckling experiments.
analogous to the wall buckling strength of a flat plate.
For the critical stress and strength over the proportional limit a coefficient was considered to fit the experimental results.
