ASSESSMENT FOR LOCAL BUCKLING COEFFICIENT OF I-SECTION WEB UNDER UNIFORM COMPRESSION

Mathematically, the buckling phenomenon can be defined as a bifurcation in the solution to the equations of static equilibrium that leads to failure. In practice, buckling is characterized by a sudden failure of a structural member under high compressive stresses; meanwhile, the actual stress at the point of failure is less than the ultimate compressive stress that the material is capable to withstand. Unlike columns, plates continue to carry the load in a stable post buckling behavior. The aim of this study is to assess the local buckling coefficient given in the design codes for the web of steel I-section under uniform compression. A comprehensive finite element buckling analysis has been performed to evaluate the local buckling coefficient. A 3D finite element modeling of a panel of pinned I-section column subject to uniform compression has been considered with a broad spectrum of cross-sectional dimensions and panel aspect ratio. A linear regression analysis has been performed to formulate a simplified equation to calculate the local buckling coefficient for particular panel parameters. The results have shown good fitting for the proposed equation; in addition, it has been concluded that an enhancement can be achieved in local buckling capacity of design codes.