Abstract
This paper clarifies the buckling strength and the deformation capacity of high strength structural steel tubes by the stub and long column tests, and the limitation of the diameter-to-wall thickness ratios (D/t) is obtained. Three series of stub columns and two series of long columns with different yield stresses are tested under pure axial compression.
The experimental results indicate that the structural characteristics of stub columns are well described by the non-dimensional parameter αc which is; αc=(E/σcy)/(D/t) for ordinary mild structural steel tubes. The limitation of D/t ratio for ordinary mild structural steel tubes can also be applied for high strength structural steel tubes as, D/t≤2400/σy, (σy in kg/mm2) More strict limitation, if a large deformation capacity is required, will be, D/t≤800/σy
The maximum strength of the long columns can be estimated by the Johnson's parabolic equation.
