Study On The Local Buckling Influence Of The Capacity Of Axial Compression Q420 High-strength Angle Column

With the rapid development of power industry, the transmission line voltage level becomes rising and transmission tower becomes larger-scale than before. High-strength angle is more and more extensively applied. In order to reduce weight, reduce the slenderness ratio between the main section, increase the radius of gyration and increase the capacity of cross section, the thin angle section often is used in the design of transmission tower. These lead to relatively large width-thickness ratio, and lead local buckling to occur prior to overall instability, which makes the angle column's overall stability capacity down. Therefore it is a necessity that studying the limit of width–thickness ratio and the influence of the local buckling capacity to the whole stability and proposing the practical calculation method.At present, the study of Q420 high strength-angle steel's local buckling has seldom been investigated. This paper studies the local buckling of Q420 axial compression high-strength equal-angle steel with large width-thickness ratio. At first, it is compared with related specifications to find problems. Then, finite element software is used to make numerical simulation and analyze the width-thickness ratio limit of the related specifications and the practicality of calculation method considering local buckling. Then, formula of the width-thickness ratio limit of Q420 high strength equal-angle steel can be derived according to equal stability principle. At last, the formula considering local buckling in DL/T5154-2002 can be amended using the width-thickness ratio limit, and the practicality of the formula can be proofed by test and the finite element software.