FUZZY ANALYSIS OF BUCKLING LENGTHS OF STEEL FRAME

The buckling length is a typical vague characteristic, which is the frequent cause of uncertainty in the design of steel structures with slender columns under compression. In complex structures with numerous load case combinations, it is not common practice to perform the stability calculation for all loading cases; another source of uncertainty is in the determination of the joint stiffness and their combinations. The buckling length of a member of a structural system is therefore frequently chosen for all loading cases as one value by the designer’s expertise. The buckling length cannot be statistically evaluated. It is a typical vague characteristic of the solution that can be mathematically modelled utilizing fuzzy sets.